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The purpose of the paper is to investigate the moisture absorption-desorption kinetics of leather, a natural collagen fibrous structure, by the application of Vickerstaff¿s method that enables to determine the diffusion coefficient of dyes in fibres, to the diffusion coefficient of moisture in leather. Leather has been fatliquored and finished in order to evaluate the effect of these treatments on moisture diffusion. Samples were subjected to ascending and descending steps of relative humidity, to cause absorption/desorption of moisture in leather. The amount of moisture absorbed/desorbed is measured as regain (% odw). At each step the final regain (at equilibrium) X, the half absorption/desorption time t¿, the ratio X¿/t¿ being X¿=X/2 that corresponds to the diffusion rate were calculated. Following Vickerstaff¿s method the maximum slope of the normalized absorption plot X(t)/X vs. ¿t enabled us to derive the square root of the apparent coefficient of diffusion DA which is based on the % of moisture absorbed/desorbed by a unit of sample mass per unit of time. Hysteresis depends on the water activity (RH%/100) of the environment and points out the energy at which the moisture absorbed at this humidity level is linked to the substrate. The higher the relative humidity, the lower the bonding energy of moisture. At lower water activities the absorbed moisture is linked to collagen as primary water. The comparison of the regain in desorption Xd vs. regain in sorption Xa at different humidity levels yields the hysteresis at each humidity level: Hyst (%) = 100 * (Xd-Xa)/Xa. Fatliquors mainly affect the maximum sorption capacity of leather, decrease the size of the monolayer although makes to ascend the bonding energy. Significant differences in the apparent diffusion coefficients between fatliquors have been observed. The highest coefficients were those of sulphited triglycerides of colza oil and sulphited fish oil, while the lowest were those given by the non fatliquored leather and that fatliquored by the combination of sulphited triglycerides of colza oil and fatty polymer. As regards the effect of finishing according to the relative humidity, finishing enhances the diffusion coefficient in the intermediate range of humidities between30 and 65% while differences decrease at the extreme values.

Industrially textured PLA multifilaments were heat set under different conditions at 110 ºC for 1 min and subjected to one cycle of deformation up to 20%. Thermal transitions of the original textured, heat set and cyclic strained filaments were measured using differential scanning calorimetry from 25 to 250 ºC. Cyclic deformation induces an endo-exo transition at peak temperatures between 55 - 60 ºC that is not observed in the original textured and heat set multifilaments. There is another endo-exo transition with peak temperatures between 67 and 72 ºC in all filaments, the intensity of which varies according to texturing conditions, heat setting and cycle strain. Texturing conditions, heat setting and cyclic strain play a role in thermal transitions, the strain at breaking and elastic properties of the filaments. The crystallinity and magnitude of the endo-exo thermal events detected by DSC are related to the strain at breaking and elasticity of polylactide textured multifilaments

Objetivo: La Degeneración Macular Asociada a la Edad (DMAE) en su forma húmeda supone una grave enfermedad que condiciona ceguera legal en muchos pacientes y con mal pronóstico si no es tratada. Pretendemos establecer una guía de actuación clínica con las diferentes opciones terapeúticas que existen en el momento actual, que puedan ayudar al oftalmólogo en su práctica clínica. Métodos: Un grupo de expertos en retina médica seleccionados por la SERV han evaluado los resultados de los diferentes estudios publicados con los fármacos actualmente disponibles, llegando a un consenso basado en la evidencia. Se han establecido unas recomendaciones para el diagnóstico, tratamiento y seguimiento de los enfermos con DMAE húmeda. Resultados: La inyección intravítrea de ranibizumab a la dosis de 0,5 mg permite obtener mejorías significativas de la agudeza visual en lesiones subfoveales, según los datos obtenidos de estudios con máximo nivel de evidencia. Debe ser considerado como el fármaco de primera elección. El empleo de bevacizumab, fármaco sin indicación aprobada para uso intraocular, ni para el tratamiento de la DMAE húmeda, puede aportar un beneficio más próximo a los resultados obtenidos con el ranibizumab que a los obtenidos con la terapia fotodinámica (TFD) y el pegaptanib. El uso de pegaptanib sódico en inyección intravítrea a la dosis de 0,3 mg como tratamiento de lesiones subfoveales permite obtener resultados parecidos a la TFD, pero en un abanico más amplio de lesiones Conclusiones: Los resultados de los estudios basados en la evidencia constituyen una buena guía de actuación en el tratamiento de esta enfermedad. Objective: Age related macular degeneration (ARMD) in its neovascular form is a serious disease which produces legal blindness in many patients with poor prognosis if left untreated. We intend to establish a clinical guide with the different therapeutic options that exist nowadays, which may help the ophthalmologists in their clinical practice. Methods: A group of medical retina experts selected by SERV have evaluated the results of different published studies with the drugs currently available, obtaining an evidence-based consensus. Some recommendations have been established for diagnosis, treatment and monitoring of patients with neovascular ARMD. Results: The intravitreal injection of ranibizumab at a dosage of 0.5 mg produces significant improvement of visual acuity in subfoveal lesions, according to data obtained from studies with the highest level of evidence. It should be considered as a first choice drug. The use of bevacizumab, a drug with not approved indication for intraocular use, nor for the treatment of neovascular ARMD can reach a result which is closer to the ones obtained with ranibizumab than to those obtained with photodynamic therapy (PDT) and pegaptanib. The use of intravitreal pegaptanib sodium in intravitreal injection at a dosage of 0.3 mg as a treatment for subfoveal lesions can obtain similar results to the TFD, but with a wider range of injuries. Conclusion: The results of the evidence-based studies are a good guide for the treatment of this disease.