Algoritmo de filtrado multi-termino para la obtención de relaciones jerárquicas en la construcción automática de un tesauro de descriptores

The new techniques of domain analysis (thematic, etc.) supply methods to create repositories or sets of structured information. A specific methodology to automatically generate domains (thematic, etc.) uses as repository a structure based on documental thesauri. One of the stages described in this methodology to generate a thesaurus is the acquisition of concepts using statistical techniques to filter information. This paper presents modifications to these filtering techniques to obtain composite terms.<br><br>Las nuevas técnicas de análisis de dominios (temáticos, etc.) proporcionan métodos para la construcción de repositorios o conjuntos de información estructurada. Existe una metodología específica para generar automáticamente dominios (temáticos, etc.) que utiliza como repositorio una estructura basada en los tesauros documentales. Una de las fases indicadas en esta metodología para la generación del tesauro es la adquisición de conceptos, que utiliza técnicas de filtrado de información estadísticas. En este trabajo se presentan modificaciones a estas técnicas de filtrado para proporcionar términos compuestos

Experiencias de salvaguardia del patrimonio cultural inmaterial

A diez años de haber sido aprobada por la Asamblea General de la UNESCO, la Convención Internacional para la Salvaguardia del Patrimonio Cultural Inmaterial ha sido ratificada por 155 de los 195 estados miembros, lo cual la convierte en uno de los instrumentos internacionales que mayor consenso ha tenido en la historia de este organismo internacional. En efecto, el patrimonio inmaterial y su salvaguardia han despertado muchos y muy diversos intereses, tanto a nivel local como global, así como entre una gran diversidad de actores sociales. En 2010, El Archivo de la Palabra organizó en la Escuela Nacional de Antropología e Historia (ENAH) el Primer Congreso sobre Experiencias de Salvaguardia del Patrimonio Cultural inmaterial

Twelve-Month Clinical and Histopathological Performance of a Novel Synthetic Cornea Device in Rabbit Model

PurposeTo report the biological stability and postoperative outcomes of a second-generation, single-piece, flexible synthetic cornea in a rabbit model. MethodsDevice materials and design were amended to enhance biointegration. Optic skirt design devices were made from compact perfluoroalkoxy alkane with porous expanded polytetrafluoroethylene ingrowth surface overlying the skirt and optic wall. Sixteen devices were implanted into intrastromal pocket in rabbit eyes. Rabbits were randomly assigned to 6- and 12-month follow-up cohorts (n = 8 in each) postoperatively. Monthly examinations and optical coherence tomography assessed cornea-device integration, iridocorneal angle, optic nerve, and retina. ResultsThere were no intraoperative complications. All devices were in situ at exit, with clear optics. No retroprosthetic membrane, glaucoma, cataract formation, or retinal detachment was observed. Two rabbits in the 6-month group had mild, focal anterior lamella thinning without retraction adjacent to the optic near tight sutures. Three postoperative complications occurred in the 12-month group. One rabbit diagnosed with endophthalmitis was euthanized on day 228. Mild sterile focal retraction of anterior lamella occurred in two rabbits, which were terminated on days 225 and 315. Light microscopic examination of enucleated globes demonstrated fibroplasia with new collagen deposition into the porous scaffold without significant inflammation, encapsulation, or granuloma formation. ConclusionsClinical evaluations, imaging, and histopathological findings indicate favorable outcomes of this synthetic corneal device in a rabbit model. Early feasibility studies in humans are being planned. Translational RelevanceFavorable 12-month results of the device in rabbits demonstrate vision-restoring potential in corneally blind individuals at high risk of failure with donor keratoplasty

Photodynamic antimicrobial therapy to inhibit pseudomonas aeruginosa of corneal isolates (Conference Presentation)

Keratitis associated with Pseudomonas aeruginosa is difficult to manage. Treatment includes antibiotic eye drops, however, some strains of Pseudomonas aeruginosa are resistant. Current research efforts are focused on finding alternative and adjunct therapies to treat multi-drug resistant bacteria. One promising alternate technique is photodynamic therapy (PDT). The purpose of this study was to evaluate the effect of riboflavin- and rose bengal-mediated PDT on Pseudomonas aeruginosa keratitis isolates in vitro. Two isolates (S+U- and S-U+) of Pseudomonas aeruginosa were derived from keratitis patients and exposed to five experimental groups: (1) Control (dark, UV-A irradiation, 525nm irradiation); (2) 0.1% riboflavin (dark, UV-A irradiation); and (3) 0.1% rose bengal, (4) 0.05% rose bengal and (5) 0.01% rose bengal (dark, 525nm irradiation). Three days after treatment, in dark conditions of all concentration of riboflavin and rose bengal showed no inhibition in both S+U- and S-U+ strains of Pseudomonas aeruginosa. In 0.1% and 0.05% rose bengal irradiated groups, for both S+U- and S-U+ strains, there was complete inhibition of bacterial growth in the central 50mm zone corresponding to the diameter of the green light source. These in vitro results suggest that rose bengal photodynamic therapy may be an effective adjunct treatment for Pseudomonas aeruginosa keratitis

Design and Biocompatibility of a Novel, Flexible Artificial Cornea

We sought to introduce the materials, design, and biocompatibility of a flexible and suturable artificial corneal device. Single-piece, fully synthetic, optic-skirt design devices were made from compact perfluoroalkoxy alkane. The skirt and the optic wall surfaces were lined with a porous tissue ingrowth material using expanded polytetrafluoroethylene. Full-thickness macroapertures around the skirt perimeter were placed to facilitate nutrition of the recipient cornea. Material properties including the skirt's modulus of elasticity and bending stiffness, optic light transmission, wetting behavior, topical drug penetrance, and degradation profile were evaluated. The final prototype suitable for human use has a transparent optic with a diameter of 4.60 mm anteriorly, 4.28 mm posteriorly, and a skirt outer diameter of 6.8 mm. The biomechanical and optical properties of the device closely align with the native human cornea with an average normalized device skirt-bending stiffness of 4.7 kPa·mm4 and light transmission in the visible spectrum ranging between 92% and 96%. No optical damage was seen in the 36 devices tested in fouling experiments. No significant difference was observed in topical drug penetrance into the anterior chamber of the device implanted eye compared with the naïve rabbit eye. The flexibility and biocompatibility of our artificial cornea device may offer enhanced tissue integration and decreased inflammation, leading to improved retention compared with rigid keratoprosthesis designs. We have developed a fully synthetic, flexible, suturable, optic-skirt design prototype artificial cornea that is ready to be tested in early human feasibility studies