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Graphite fiber reinforced magnesium composites have been fabricated by infiltration and liquid phase hot pressing techniques. Although pure magnesium does not wet graphite, weting and bonding were achieved by precoating the graphite fibers with titanium. Tensile strengths and elastic moduli of flat rectangular composite specimens were measured and compared with Rule of Mixtures strengths. Significant strengthening and stiffening were achieved. Tensile strength was increased by 170 pct and the elastic modulus by 100 pct. Measured elastic moduli were in good agreement with Rule of Mixtures values. The highest tensile strength was about 83 pct of the Rule of Mixtures strength. It is believed that specimen porosity and fiber misalignment account for the bulk of this difference and that an improved fabrication technique will yield specimens with higher strengths. Fracture modes are presented and discussed.

To study epic tradition is to study not “influences” (which may serve to buttress preconceived notions) but rather the ways in which major poets modified the tradition. Such study can be a way into meaning, particularly in poems as complex as the Aeneid and Paradise Lost. In both poems, the epic strategy relies on modification in the catalogue and battle conventions. In Vergil's catalogue (Book VII), language and imagery embody the conflict which informs the whole poem, arma-virum. The battle scenes (IX, X) develop this conflict. On both the Latin and the Trojan side, strategy fails and bloodlust triumphs. Aeneas’ rampage (X) climaxes the ascendancy of power over justice (or fortitudo over sapientia). In Paradise Lost, in the catalogue and Mulciber passages of Book I, syntax and imagery develop the theme of specious identity; in II and IV, Milton exploits the potential of epic battle, then deliberately aborts the battle with modified “recognition scenes.” The War in Heaven develops the fortitudo-sapientia motif. But it is only in the love to which Michael firmly leads Adam's understanding (XII) that fortitudo and sapientia are reconciled.

Investigations in guinea pigs to evaluate interferences between cholestasis and enzymatic induction by phenobarbital, and influences that both experimental conditions exert on the levels of gamma-glutamyl transpeptidase in microsomes and other subcellular fractions, have shown that: 1) cholestasis inhibits inductions of cytochrome P-450 from phenobarbital; 2) gamma-glutamyl transpeptidase is not an inducible enzyme in guinea pig; 3) rises or ferum gamma-glutanyl transpeptidase produced either by cholestasis or phenobarbital administration, are not related to an increased enzymatic synthesis in the various subcellular fractions of liver cell.

Three experiments are described in which seven tritium-labeled glycosphingolipids were prepared by catalytic addition of tritium gas to unsaturated centers. These compounds include glucosyl ceramide, galactosyl ceramide, lactosyl ceramide (cytolipin H), N-acetylgalactosaminyl (β1 → 3) galactosyl (α1 → 3) galactosyl (β1 → 4) glucosyl ceramide (cytolipin R), and three species of gangliosides: GM1 (G4), GM3 (G6), and GD1a (G3).

The enzymic synthesis of brain gangliosides proceeds via a stepwise addition of monosaccharide units from sugar nucleotides to glycosphingolipid acceptors. Several possible pathways for ganglioside biosynthesis have been proposed (s. Scheme) utilizing this mechanism. Preliminary reports by Steigerwald et al. (1) and Kaufman et al. (2) have described a particulate embryonic chick brain preparation which would catalize the synthesis of gangliosides via the sequence of reactions 2, 3, and 4. The demonstrations in brain of reaction 3 in the frog (3) and rat (4, 5), reaction 4 in the frog (3, 6, 7) and rat (5, 8, 9), and reaction 2 in frog (Table I) suggests that this pathway is probably universal in vertebrates.