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The damage process of plain and blended cement mortars subjected to sulfate attack under electrical field was investigated in this paper. The deterioration of mortars was investigated by measuring the loss of compressive strength. To identify the changes of microstructure and mineral phases after the test, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction analysis were performed on the selected samples. The results indicated that compared with sulfate attack alone, the combination of sulfate attack and electrical field accelerated the damage process of mortars, which can be explained through two different mechanisms. On the one hand, Ca 2+ ions directionally moved and then leached out from mortars under the electrical field, leading to the dissolution of portlandite as well as the decomposition of C-S-H gel at the later stage. On the other hand, the electrical field accelerated the migration of sulfate ions and then they reacted with hydration products to form massive ettringite and gypsum, which resulted in the microcracks and strength loss of mortars. Moreover, the deterioration of the mortar blended with fly ash was still visible in spite of its better chemical resistance. The strength loss of limestone powder incorporated mortar increased in comparison with Portland cement mortar as a result of an increase in porosity.

The transduction efficiency and cell tropism of viral vectors rAAV2/1, rAAV2, Ad5, Ad5/F35, and Lentivirus were evaluated in retina. All viral vectors achieved efficient transduction in living rat retina. However, each vector showed distinctive efficiency in vitro especially for rAAV2/1, which displayed poor transduction in cultured retinal cells. Distinctive cell-specific GFP expression was observed in vivo and in vitro for the same viral vector. The cell-specific tropism was not strictly correlated with the correspondent distribution of viral receptors in retina. These results provided important insights into the selection of appropriate vectors when specific retinal diseases are considered for gene therapy.

This paper presents a study on sulfate resistance of mortars blended with and without silica fume or fly ash under electrical field. Performance of the mortars was determined by various means such as visual examination, sulfate concentration, flexural and compressive strength, as well as mineralogical analysis. The results showed that electrical field accelerated the deterioration induced by sulfate attack, as it sped up the ingress of sulfate ions into the mortar. The use of mineral admixtures improved the sulfate resistance of mortars. However, a relatively great amount of migrated sulfate as well as expansive sulfate products (gypsum and ettringite) were still found in the blended cement mortars under the electrical field, for which their deterioration was also notable. Therefore, the electrical field also accelerated sulfate attack on the mortars blended with mineral admixtures.

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