Oka varicella vaccine has been used to confer active immunity to varicella-zoster virus (VZV) in healthy and immunocompromised hosts. Based on its attenuated nature, Oka varicella vaccine expressing human immunodeficiency virus (HIV) env antigen was constructed by inserting the HIVenv gene into the viral genome and its immunogenicity was assessed in guinea pigs. The HIVenv gene encoding 296-463 amino acids was inserted between the sequences of the hepatitis B surface antigen and the thymidine kinase gene of the cloned plasmid and the recombinant virus was isolated by cotransfection of the chimeric plasmid with viral DNA. Insertion of the HIVenv gene into the viral genome was confirmed by PCR and sequencing of the viral genome of the recombinant virus. The recombinant virus expressed 30k HIVenv fusion protein in its infected cells. In guinea pigs, immunization with the recombinant virus induced an antibody response to both the HIV antigen and the V3 peptide of gp120 as well as VZV gE:gI. Cell-mediated immunity to the HIV antigen and gE:gI was assessed by the cutaneous reaction representing delayed type hypersensitivity. Immunized guinea pigs responded well to both the HIV antigen and gE:gI. Thus the recombinant Oka varicella vaccine expressing the HIVenv antigen induced both a humoral and cell-mediated immunity to the HIV antigen similar to VZV as Oka varicella vaccine induces humoral and cell-mediated immunity to VZV in the vaccinees. This recombinant Oka varicella vaccine expressing the HIVenv antigen may be evaluated for its immunogenicity as one of the AIDS vaccine candidates.

An experimental study on the absorption of low concentration sulfur dioxide into limestone slurries in a stirred tank reactor has been performed. The absorption rates under various experimental conditions were measured and the absorption processes have been discussed. The analysis of the experimental data shows that the limestone dissolution process seems to play a very important role in the absorption.

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Axisymmetric jets have been observed to investigate the effect of controlled pulsation on the behavior of vortex rings by using the hydrogen bubble technique and hot-film measurement. Pulsed jets had similar velocity profiles in the initial region and in the fully developed region. This similar velocity profile was coincident with that in natural jets. The differences between the two kinds of jets in volume rate, in decay of centerline velocity and in distribution of turbulent intensity, were observed to be remarkable in the initial region. Such differences were caused by the different behavior of vortex rings in the initial region. Behavior of vortex rings in the initial region of pulsed jets was roughly classified into three types by Strouhal number, Sr0 (Sr0 <0.9, 0.9^Sr0 < 2.6, Sr0^2.6). It was found that the pulsation for Sr0 =0.3 was the most dispersive wave in a jet column.

An experimental study on the absorption of low concentration nitrogen monoxide into aqueous KMnO,/NaOH and Na,SO,/FeSO, solutions has been conducted with two types of absorbers, a stirred tank and a bubble chamber. The absorption rates under various experimental conditions were measured. In the case of NO absorption into KMnO,/NaOH solutions, the rate is proportional to both the interfacial concentration of NO and either that of a complex formed in the solution or that of KMnO, depending on the pH values of the solutions. In the case of Na,SO,/FeSO, solutions, the rate shows the maximum at a certain concentration of Na2S03. The reaction mechanism involved seems not to be simple since the reaction orders with respect to Na,SO, and FeSO, are not integers. The experimental data have been analyzed by the (m ,n)th-order reaction model and equations for NO absorption rates have been presented.