The study of the antigenic properties of tissues and organs of animals in ontogenesis
SummaryThe antigenic properties of the tissue of developing crystalline lens of ducks was studied with the aid of anaphylactic reaction with desensitization.Morphogenesis, the rate of growth of crystalline lens and content of ribonucleic acid (RNA) in it were investigated simultaneously. It was demonstrated that during the early stages of embryogenesis (90–130 hours) the antigens are present in the tissue of developing crystalline lens, which are specific only for the definite stage of development (stage-specific antigens). There is formation and intensive growth of the primary fibers of the crystalline lens and increased concentration of the RNA during this period.
Fetuin, a New Globulin Isolated from Serum
DURING a study on the fractionation of serum with ammonium sulphate, I thought it worth while to try whether some of the serum proteins could be isolated more easily from the serum of a newly born animal. Serum from calves not more than two weeks old was used for these fractionation experiments, which immediately indicated a pronounced difference between the serum from the calf and that from the cow. Ultracentrifugal examination of the different fractions revealed the presence of large amounts of a globulin with the sedimentation constant, s20, of the order 3S (1S (Svedberg) = 1 × 10−13 C.G.S.) as compared with the normal s20 ∼ 7S for serum globulin. The main part of the new protein was precipitated between the salt concentration limits 0.37 and 0.45 saturated ammonium sulphate. It was purified further by fractionation with ammonium sulphate and centrifugation in a high-speed air-driven centrifuge. Molecular weight determination gave a value of the order 50,0001.
The role of dissolved oxygen in supercritical water in the oxidation of ferritic–martensitic steel
Abstract To assess the role of dissolved oxygen in supercritical water on the growth processes of oxide scales, a marker experiment of ferritic–martensitic steel was performed by exposing to supercritical water (H 2 16 O) containing marked 18 O 2 at 600 °C under 25 MPa. The oxide scale was analysed by using Secondary Ion Mass Spectrometry (SIMS). The oxygen isotope profile shows that dissolved oxygen and supercritical water react with metals simultaneously. Dissolved oxygen changes the oxidation/reduction potential of supercritical water leading to an increase in the oxidation rate. The oxidation rate increases with increase in dissolved oxygen content in supercritical water. The mechanism of the effect of dissolved oxygen on oxidation is discussed.