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In experiments under precisely controlled conditions, an inverse linear slope 1 relationship between log canine distemper (CD) virus concentration and log CD neutralizing antibody titer was not demonstrated. The data indicate that a method of mathematical interpolation whereby serum titers are converted to “antibody units” will not be in accord with experimentally determined in ovotest results. Possible standard procedures that might make possible direct comparison of test results reported by different laboratories are discussed.

It has long been an accepted fact that through experimental operations on the pancreas conditions may be produced that lead to certain changes in the urine. On the other hand, until 1904, when the work of Cammidge first appeared, there was not known in clinical medicine any alteration in the constituents of the urine, which was regarded as characteristic of, or as indicating, disease of the pancreas.At that time Cammidge, of London, described in the Arris and Gale Lecture1 his studies on the urine of patients suffering from pancreatic disease, and the reaction he then described has since become known as the "pancreatic reaction of Cammidge." As the direct result of criticism of his technic and conclusions, that author modified his procedure until he finally published his "improved" or "C" reaction, which is supposedly free from error. THE WORK OF CAMMIDGE. Briefly stated, the present contention of Cammidge

Mutant strains of Rhodospirillum rubrumare isolated which are blocked in different stages of pigment synthesis. In these strains the morphogenesis of thylakoids and the pigment production are investigated. Concerning bacteriochlorophyll synthesis two groups of mutants are separable. The members of the first group synthesize bacteriochlorophyll. Some of these mutants excrete bacteriopheophytin. The strains of the second group are not able to synthesize bacteriochlorophyll. Members of both groups excrete bacteriochlorophyll precursors into the cultural medium. These pigments were identified by their spectral properties as Mg-2,4-divinyl-pheoporphyrin a5-monomethylester, pheophorbide a, and 2-devinyl-2-hydroxyethyl-pheophorbide a. Thylakoids are only formed by those strains which are able to synthesize bacteriochlorophyll. However, small amounts of bacteriochlorophyll can be produced without a concomitant thylakoid synthesis. The fatty-acid pattern in some mutants is modified quantitatively. However, the results do not indicate any correlation between disturbance of thylakoid morphogenesis and a deviation of fatty-acid composition. Fatty acids seem to have no special functions in thylakoid morphogenesis. The membranes of the mutants were isolated, split into protein subunits, and these were separated by disc electrophoresis. A characteristic protein pattern, first of all a high content of fraction E, is correlated with the ability to form thylakoids. In addition, all mutants which synthesize bacteriochlorophyll contain a fast-migrating membrane protein (zone G). The results suggest that the whole bacteriochlorophyll-protein complex is necessary for thylakoid formation.

A basic solution for in-reactor sag of horizontal pressure tubes is proposed in accordance with a nonlinear anisotropic creep theorem. As an example, numerical solutions for in-reactor sag of cold-worked zircaloy-2 pressure tubes supported at the ends only are given for various combinations of anisotropy coefficients. It is shown that an isotropic analysis may overestimate or underestimate the deflection due to sag by about 100 percent if hoop creep rates are about 50 percent smaller or larger than longitudinal creep rates.

MYOTONIA, the denominating characteristic of three genetically determined diseases of muscle (myotonia congenita, myotonia dystrophica, and paramyotonia), and dystrophy of muscle fibers, a feature of one of these diseases (myotonia dystrophica), remain obscure.Concerning the localization of myotonia, a number of investigators believe it might reside in the muscle cell. Grund1 and later Schaffer2 noted the persistence of this phenomenon after complete block of the nerve fibers supplying the muscle; and Gregor and Schilder3 and later Lindsley and Curnen4 observed it during the relaxation phase of contraction, when few nerve impulses were reaching the muscle. Brown and Harvey5 in a myotonic disease of goats also demonstrated that complete denervation of muscle failed to abolish the myotonia. Landau6 and Floyd et al7 have shown that curare has no effect on human myotonia. Denny-Brown and Nevin8 confirmed this localization but also obtained evidence

Observations made with the grating interferometer suggest that it may be useful for the study of fine structure. It is hoped that the peculiarities of the instrument and a satisfactory procedure for its application to a study of fine structure of spectral lines can be described in a later paper. At present certain optical properties of the instrument are catalogued. The optical properties are themselves interesting and will be found useful in discussing applications which may be described subsequently.