Prolonged Immunization

Rabbit anti-mouse erythrocyte sera from each of 7 courses of immunization were studied with 9 immunologic techniques, namely, agglutinin titrations with antiglobulin serum, in serum-albumin medium, with papain treated cells, and in saline medium; hemolysin and complement fixation titrations; determination of combining ability with fluorescein and I125 labeled sera; and production of anemia in mice. Formalinized erythrocytes can be used successfully to study certain immunologic reactions. In vitro reactions, except for complement fixation and coating with fluorescent antibodies, did come near their peak levels in 2-course sera; after 4 or more courses, titers of all in vitro reactions were essentially parallel to the base line. Whether these tests are demonstrating different reactions of the same antibody or reactions of different antibodies requires further investigation. On the other hand, the anemia producing ability showed marked decrease in sera collected after more than 3 courses of immunization. Our studies permit the conclusion that no in vitro reaction has yet been found to serve as a reliable indicator of the in vivo potency of a rabbit anti-mouse erythrocyte serum.

High-Pressure Polymorph of Iron

An x-ray diffraction study of iron under pressure has shown that alpha-iron (body-centered cubic) transforms to hexagonal-close-packing (designated epsilon-iron) at 130 kb, room temperature. The volume change for the transformation is -0.20 +/- 0.03 cm2/ mole. The slope for the gamma-epsilon phase boundary has been calculated to be 2 +/- 1 degrees C/kb. The molar volume of iron decreases from 7.10 cm3/mole (density = 7.85 g/cm(3)) at room pressure to 6.10 +/- 0.08 cm(3)/mole (density = 9.1 +/- 0.1 g/cm(3)) at 200 kb and room temperature. The extrapolation of the gamma-epsilon phase boundary, consistent with shock wave data, suggests that it may have an influence on the properties of the earth's core.

Sheep Erythrocyte Agglutinins and Beef Erythrocyte Hemolysins in Infectious Mononucleosis Serum

In serum of patients with active infectious mononucleosis, the titers of sheep agglutinins and beef hemolysins were consistently elevated, while those of sheep hemolysins and beef agglutinins were within normal levels. In general, sera with higher titers of sheep agglutinin had also more beef hemolysin. In the course of illness, the change in titers was parallel. The absorption patterns of sheep agglutinins and beef hemolysins were generally similar. Both antibodies were demonstrated in the same serum fractions after separation by electrophoresis and by column chromatography. The ultracentrifugal data and the results of treatment with sulfhydryl compounds pointed to their association with macroglobulins. Beef hemolysin was more sensitive to temperature changes than sheep agglutinin.

Our results indicate that sheep agglutinins and beef hemolysins are physically inseparable but may possess different combining sites responsible for agglutination and hemolysis.

Surface Textures of Sand Grains—an Application of Electron Microscopy: Glaciation

To simulate glacial conditions, a mixture of ice and quartz grains was subjected to grinding under hydrostatic pressure of 500 bars. Electron microphotographs of these "synthetic" glaciated surfaces were then compared with electron microphotographs of grain surfaces which had been abraded and crushed by glacial action, and the correspondence was found to be good. Thus it appears possible to distinguish glacial sands from beach and eolian sands byexamining the surface textures of these grains with the electron microscope.

Surface Textures of Sand Grains: An Application of Electron Microscopy

Crushed quartz was subjected to wind, ball mill, and shaking-table action to simulate eolian and beach conditions. Electron microphotographs of these surfaces were then compared with those of grain surfaces which had been frosted naturally, and the correspondence between them was good. Thus, the transportation history of many sand deposits may be identified by this technique.