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The crystal structure and site preference of Co2+ in a synthetic Co1.10Mg0.90SiO4 olivine have been determined from single crystal X-ray diffraction data collected on an automatic diffractometer. The R factor is 0.044 for 612 reflections. The site occupancies are: Ml site: Co 0.730±0.006; Mg 0.270; M2 site: Co 0.370, Mg 0.630. The Gibbs free energy change, ?G° for the ion-exchange reaction between M1 and M2 sites is -4.06 kcals/mole, assuming ideal mixing at each set of sites. This energy may be called ‘site preference energy’ of Co2+ in olivine. The strong preference of Co2+ for the M1 site can be quantitatively explained by two competing forces: preference of ions larger than Mg2+ for the M2 site and stronger covalent bonding of transition metal ions at the M1 site. For Fe2+, Mg2+, these two effects nearly neutralize each other, explaining the lack of considerable cation-ordering in Fe-Mg olivines.

A rabbit 7 S antibody reacting specifically with a tumor associated antigen on the surface of mouse EL4 lymphoma cells could form “““caps””” and subsequently undergo endocytosis even when the antibody was non-covalently bound to chlorambucil. As the alky-lation of nuclear DNA appears to be the basis of tumor inhibition by alkylating agents like chlorambucil, facilitation of the transport of chlorambucil across cell membrane by anti-tumor antibodies might explain, at least in part, the increased tumor inhibition by chlorambucil bound anti-tumor antibodies compared to tumor inhibition by equivalent amounts of tumor antibodies or chlorambucil alone.

Immunohistochemical examination of pulmonary sarcoid lesions from three patients revealed in all the presence of clumps of immunoglobulin and complement in those granulomas which were not completely fibrosed. Similar examination of lung biopsies from 36 patients suffering from a variety of chronic lung diseases but not sarcoidosis showed clumps of immunoglobulin and complement in and around the lesions of only one patient suffering from allergic pulmonary alveolitis. This observation supports the contention that the lesions of sarcoidosis might have an immunologic basis.

A quantitative determination of Ni from a large number of basaltic rocks of India of different geological ages has been made. The present study gives an average of 66 ppm Ni for 55 analyses of Indian basalts. The olivine tholeiites and alkali olivine basalts contain, in general, more Ni than the quartz tholeiites. The upper Deccan basalts are entriched in Ni compared to the Lower Deccan basalts. It is observed that the amount of Ni is controlled by both Mg and Fe+2 contents of basalts. However, in the present study an apparent correlation of Ni with Fe+2 is noteworthy.

Eutectic compositions and temperatures in the system Qz—Or—An— H2O have been determined at 4 and 7 kb water pressure. Eutectics are now known in the pressure range from 2 to 7 kb (Tab. 1). This provides necessary information about the important granitic system Qz—Or—Ab—An—H2O.

The incidence of leukemia is higher among those closely exposed than among those more remote from the hypocenter. This increase was first manifest approximately three years following exposure. It apparently reached its peak between the years 1950 and 1952. Thereafter, the incidence has been diminishing, but 13 years after exposure it is still higher than would be expected in the general population. The type of leukemia most increased in incidence is the chronic granulocytic variety. No apparent difference in the natural history of the specific types of leukemia in exposed and nonexposed Japanese has been observed. Preliminary analyses of the data show a linear relation between dose of radiation and incidence of leukemia above 50 to 100 rad. Below this dose, the shape of the curve is not certain.

The variation of the free fraction of serum vitamin B12 level was studied in certain hematologic disorders. In normals, the mean ratio of free to total vitamin B12 was 10.2 per cent. In leukemias—chronic myeloid, acute myeloid and acute lymphatic—the mean value of free vitamin B12 was higher than normal. In chronic myeloid and acute lymphatic leukemias, the free vitamin B12 level did not on an average exceed 20 per cent of the total. In acute myeloid leukemia, the free fraction was relatively more increased, constituting 31.1 per cent of the total on an average. In aplastic anemia, the mean values of free vitamin B12 and the ratio (31.2 per cent) of free to total vitamin B12 were higher than normal. The patterns presented by acute myeloid leukemia and aplastic anemia appeared to be more or less similar.