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The purpose of this work is the development and characterisation of new hybrid polysaccharide (FucoPol) membranes. These membranes were prepared by incorporation of a SiO 2 network homogeneously dispersed by using a sol-gel method with GPTMS as a crosslinker silica precursor. They were further crosslinked with CaCl 2 for reinforcement of mechanical properties and improvement of their permeation performance. They were characterised in terms of their structural, mechanical and thermal properties. They presented a dense and homogeneous structure, resistant to deformation, with a Tg of 43 °C and a thermal decomposition between 240 and 251 °C. The hybrid FucoPol membranes were tested for ethanol dehydration by pervaporation and also for nitrogen dehydration. They exhibited high water selectivity values, similar to PERVAP ® 4101, however they lost their stability when exposed to solutions of 10.0 wt.% water in ethanol. In contrast, these membranes were stable when applied in N 2 dehydration, leading to reproducible performance and very high water selectivities. [ABSTRACT FROM AUTHOR]

Objectives The objective of this study was to determine the effect of LLDL therapy on the gene expression of osteoblast markers of growth and differentiation. Materials and methods The MG-63 cell line was exposed to diode laser (ezLase) of 940 nm at 1–1.5 W and 3–4 J, and gene expressions (Runx-2, alkaline phosphatase [ALP], type I collagen [Col-I], osterix [OSX], osteocalcin [OSC], osteoprotegerin [OPG], bone morphogenetic protein [BMP]-2 and -7, transforming growth factor-β1 [TGF-β1], and TGF-β receptors [TGF-β R1, TGF-β R2; TGF-β R3]) were evaluated by quantitative RT-PCR. Results LLDL treatment stimulated the expression of osteoblast differentiation markers ALP, Col-I, Runx-2, and OSX in relation to the doses applied ( P < 0.05), but no changes were detected in OSC, OPG, or BMP-7 at any study dose. This effect may be mediated by TGF-β1 and BMP-2, given that the treatment increased their expression and that of TGF-β receptors R1, R2, and R3 ( P < 0.001). Conclusion These results suggest that the biostimulatory effect of laser therapy on osteoblasts may be attributable to the release of autocrine factors in response to the irradiation. A clinical trial is warranted to test its therapeutic usefulness in bone tissue regeneration and to define a treatment protocol. [ABSTRACT FROM AUTHOR]

The removal of water from gas streams, in particular flue gas and biogas, is an important industrial operation. To mimic these industrial dehydration processes, permeation of water vapour, pure gases (CO 2 , CH 4 and N 2 ) and gas mixtures containing 20 vol% CO 2 + 80 vol% N 2 and 70 vol% CH 4 + 30 vol% CO 2 , at different conditions of relative humidity, was monitored by mass spectrometry. The potential of using hybrid polysaccharide membranes obtained from a low cost carbon source (glycerol) and crosslinked using (3-Glycidyloxypropyl) trimethoxysilane (GPTMS) as silica precursor by a sol-gel method was evaluated. The hybrid membranes developed showed barrier properties to all gases studied, with a gas permeability below 1 barrer, while exhibiting high water permeabilities and selectivities. When process in a biogas mixture, the water permeability was found to be three times higher than water permeability in a flue gas mixture, leading to a H 2 O/CH 4 selectivity much higher than H 2 O/N 2 selectivity. These membranes showed, under close-to-real conditions, that they have the ability to dehydrate mixtures, with the advantage of not losing N 2 or CH 4 , due to the low permeability values of these gases. [ABSTRACT FROM AUTHOR]