CO2–CH4 conversion and syngas formation at atmospheric pressure using a multi-electrode dielectric barrier discharge

The conversion of CO2 and CH4 into value-added chemicals is studied in a new geometry of a dielectric barrier discharge (DBD) with multi-electrodes, dedicated to the treatment of high gas flow rates. Gas chromatography is used to define the CO2 and CH4 conversion as well as the yields of the products of decomposition (CO, O2 and H2) and of recombination (C2H4, C2H6 and CH2O). The influence of three parameters is investigated on the conversion: the CO2 and CH4 flow rates, the plasma power and the nature of the carrier gas (argon or helium). The energy efficiency of the CO2 conversion is estimated and compared with those of similar atmospheric plasma sources. Our DBD reactor shows a good compromise between a good energy efficiency and the treatment of a large CO2 flow rate.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Factors affecting antibody response of newborns to repeated administration of the rotavirus vaccine RIT 4237

The safety and immunogenicity of repeated doses of RIT 4237, an oral live attenuated rotavirus vaccine of bovine origin, as well as the influence of gastric acidity and maternal antibodies on the vaccine 'take rate' were studied in newborns. The vaccine was given orally on the first day of life, at 1 month, and at 2 months of age. Fifty-seven newborns entered the study but only 36 completed the trial. No adverse reaction was observed after vaccination. Immune responses were evaluated by titrating pre- and postvaccination serum antibodies to RIT 4237 by a neutralization technique. Eight of 43 (18.6%) tested infants responded to the first dose of vaccine. Subsequently another six and 11 infants responded to the second and third dose, respectively. The total cumulative response after the third dose was 23 of 36 vaccinees (63.9%). The geometric mean neutralizing antibody titers was lower in responders than in nonresponders before the first dose of vaccine indicating that maternal antibodies interfered with vaccine 'take'. Since the RIT 4237 strain is acid sensitive, gastric pH was measured at the time of each vaccination. Mean pH values in responders were not significantly different than those found in nonresponders. Therefore, vaccine failures cannot be due to inactivation of the rotavirus vaccine in the stomach but instead they can be attributed to high levels of maternal antibodies. At each vaccination, additional subjects seroconverted. Therefore, a multiple dose scheme is advisable to obtain an optimal immune response.SCOPUS: ar.jinfo:eu-repo/semantics/publishe