ABSTRACT
A mesoporous TiO(2)-SiO(2) nanocomposite photocatalyst has been prepared from TiO(2) nanoparticles and ethoxysilane oligomers in the presence of a non-ionic surfactant (n-octylamine). The 2D and 3D structure properties of the resulting nanomaterial are described. The use of 3D techniques, particularly HAADF-STEM electron tomography, together with 3D reconstructions and atomic force microscopy, provides insight into the fine structure of these materials. We find that n-octylamine creates a mesoporous silica structure in which titania nanoparticles are embedded, and that some of the titania is retained on the outer surface of the material. Rapid photodegradation of methylene blue dye is facilitated, due to the synergistic effect of: (1) its adsorption into the composite mesoporous structure, and (2) its photodegradation by the superficial TiO(2).
ABSTRACT
HTLV-1=2 antenatal screening is not mandatory in European countries. The rapid increase in immigrants coming from areas endemic for HTLV-1 infection has compelled a review of this policy in Spain. From February 2006 to December 2007, a cross-sectional study was carried out in all pregnant women attended at 10 different Spanish hospitals. An enzyme immunoassay (EIA) was used to test serum HTLV-1=2 antibodies; reactive samples were further confirmed by Western blot and=or polymerase chain reaction. A total of 20,518 pregnant women were examined, of whom 18,266 (89%) were native Spaniards. Overall, 946 (4.6%) of the immigrants came from HTLV-1 endemic areas (mainly Central and South America and sub-Saharan Africa). Four samples were EIA seroreactive for HTLV-1=2, two of them in women infected with HTLV-1 coming from endemic areas. The other two women were infected with HTLV-2; one was an immigrant from Bolivia and another was a native Spaniard who admitted prior injection drug use and was HIV-1 positive. The overall HTLV-1=2 seroprevalence was 0.19 per 1000 (95% CI: 0.05-0.49=1000). For HTLV-1, the seroprevalence was 2.11 per 1000 (95% CI: 0.26-7.62=1000) in pregnant women from endemic areas. The seroprevalence of HTLV-1=2 infection is below 0.02% among pregnant women in Spain, and therefore universal screening for HTLV-1=2 infection in antenatal clinics is not warranted. However, HTLV-1=2 screening could be considered in pregnant women coming from endemic areas, in whom the rate of infection is nearly 1000-fold higher than in native Spaniards and are the only group infected with the more pathogenic HTLV-1.
