The efficiency of multiple traversal targets is defined as the probability that a proton dies by making a nuclear collision in the target rather than by hitting the limit of the synchrotron aperture. The efficiencies of Be, Al, Cu, and Pb targets are shown for 15 and 30-Bev protons in the Brooknaven AGS. Beryllium was found to be the most efficient. (M.C.G.)

Radiation damage to graphite has several consequences of practical importance. The growth of graphite under radiation (Wigner's disease) in production reactors has always been a serious concern. The thermal conductivity of graphite decreases greatly with time of irradiation and is important in long range studies of reactor temperature problems.

This memorandum clarifies the present status of ξ measurements in the uranium-water lattices.

Innes, Zemen, Frenkel, Borner and Wright (1962) described an outbreak of encephalitozoönosis of the central nervous system in mice, a summary of which is given below for an understanding of why this appendix may be of interest. When the paper was presented for publication, the editors of the journal decided to omit the history of our mouse colony. In our opinion, to understand (a) how this infection may have arisen and (b) may have spread, and still exist in some colonies, it is of prime importance to know the history of this strain of mice used by us (and others). It also has lessons on the establishment and maintenance of so-called "disease-free" or "specific pathogen-free"* colonies of laboratory animals in general. Information on the history of the mice has been culled from Col. H. Yager, VC, Director of the Division of Veterinary Medicine, Walter Reed Army Institute of Medical Research, Washington, D. C., and from Drs, Clara Lynch and John B. Nelson, Rockefeller Institute, New York.

The theoretical and practical aspects of the accelerating mode (TM01) in iris-loaded waveguides have been covered extensively in many reports and publications. The pulse shortening observed in linacs and the possible application of an iris-loaded waveguides as the deflecting structure for rf particle separators stimulated the interest in the nature of higher order modes. Some experimental results on higher order modes in iris-loaded waveguides are available in references. Results of studies done at CERN are not yet published; they were however communicated to the authors and represented the basis of work done at Brookhaven. A preliminary account of BNL results was given in reference. The purpose of this report is to describe the model measurements which were necessary to determine the geometry of a brazed or electroformed prototype for a deflecting waveguide. At the same time, a systematic investigation of other than the deflecting mode was done to ensure a nondegenerate field solution at the operating frequency. The measurements are compared with computational results obtained on the IBM 7090 at BNL.

The purpose of this paper is to present tables of the perturbed wave functions which have been recently obtained in a calculation of the quadruple antishielding factors γ∞ for the Mn+2, Fe+3, Ga+3, and Ag+ ions. The wave functions v'1(nℓ-ℓ) which are tabulated represent the effect of the perturbation due to a nuclear quadruple moment Q on the wave functions of the outermost electrons of the ion core.

For an experiment to measure the magnetic moment of the Λ hyperon, it was necessary to extract the external beam of the Cosmotron with maximum efficiency and with minimum time duration. To accomplish this end, the standard external beam of the machine was supplemented with the Rapid Beam Ejector. It was found that, unfortunately, the ejection efficiency of the beam was less than normal when the RBE was used. Measurements of the ejection efficiency were made by irradiating polyethylene foils at the second focus of Beam 1 with 3 BeV protons. The external beam was tuned up and optimized in a standard manner. It was found that the ratio of the number of protons ejected with the RBE to the number ejected without the RBE was 0.3 in one run and 0.22 in another try. It was also observed that the RBE did not shift the position of the external proton beam focus to within ± 1/8 in.

The enzymolysis by α-chymotrypsin of the substrates, N-acetyl-L-tryptophane ethyl ester and N-acetyl-L-tyrosine ethyl ester, was followed by means of fluorescence whose intensity increased fourfold and threefold per mole respectively as substrate was transformed into amino acid. The assay by fluorescence was several orders of magnitude more sensitive than the assay by differential absorption spectra of these substances and was in agreement with it in those concentration regions where both methods overlap. To maintain linearity between concentration and fluorescence intensity, the concentration of substrate should be no greater than 10-4 M/1. In such solutions the rate of esterolysis could be followed with the enzyme at 10-11 M/1.

An isochronal differential-type microcalorimeter has been designed and constructed. As a result of its simple design it is very easy to handle the samples and assemble the calorimeter. Important to the operation of the calorimeter is a program, also working on the differential principle, that provides linear temperature rise of the samples. This calorimeter is used to measure very small energy releases such as those found in precipitation, stored energy, etc. It is demonstrated that the calorimeter is easily capable of measuring 0.0005 cal with a probable error of the order of 1% to 2%.

Cowley's measurements of the short-range order parameters, αi, in Cu3Au at T=405°C have been re-evaluated taking into account the effects of thermal vibrations and static displacements due to differing atomic sizes. The separate corrections for the thermal vibrations and the first-neighbor atomic size factor are found to be quite large, demonstrating their importance in the usual experiments. When combined, the corrections in this case largely cancel, and only the values of α1 and α3 are appreciably changed. The corrected values are: α1= -.113, α2= +.185, α3= -.009, α4= +.082, α5= -.058.

The role of the marrow as a site for antibody formation has been considered for many years. In 1912 Ludke reported the appearance of antibody in cultures of marrow cells obtained from previously immunized rabbits. Specific agglutinins for killed typhoid bacilli and lysins for ox red cells and sheep red cells were detected in the culture media 2 to 5 days later. However, the cultured cells failed to produce antibody when these antigens were added to the media. Similar findings by Reiter, Przygode, and Schilf appeared in the early literature with regard to the appearance of antibodies to various antigens in tissue cultures of bone marrow from immunized animals, along with failure to elicit antibody formation by addition of antigen to the culture resulted from the addition of excess amounts of antigen, so that if antibody synthesis occurred, the excess antigen combined with antibody and significant amounts of free antibody could not be detected in the culture media. Thorbecke and Keuning observed an increase in antibody in culture fluids when bone marrow fragments from rabbits immunized to paratyphoid B vaccine were cultured in roller tubes.

A kinetic study of the exchange of normal and radioactive bromine in graphite-bromine lamellar compounds has been made at temperatures of 30° to 50°C. Natural and synthetic graphite powders were investigated. Two alternative mechanisms for the exchange, volume diffusion and surface exchange, were considered. The data were in better agreement with the diffusion mechanism. Diffusion coefficients of 10 -9 to 10 -8 cm2/sec and an activation energy of 11 to 14 kcal/mole were calculated for the natural graphite powders. The diffusion coefficients increased with increasing bromine content. Reversibly absorbed bromine exchanged more rapidly than irreversibly absorbed bromine.

The cobalt and molybdenum positions had been derived from a three-dimensional Patterson function based on complete data out to λ-1 sin θMo≈ 1. From the separation of the separation of the Mo atoms it was thought that the structure contained free, unlinked MoO4 -2 ions, and this, together with the observed density and analyses for Co and Mo, suggested that the composition was probably Co2(MoO4)3. The paucity of structural information on complex oxide systems and the interesting properties, both structural and physical, of such systems prompted the present, detailed refinement of the structure. The result is more complicated and more interesting than had been anticipated: from the analysis of the X-ray data the compound is found to be NaCo2.31(MoO4)3, and this composition is consistent with chemical analyses. The structure shows several interesting features, including the partial occupancy of cobalt atoms in two independent CoO6 octahedral sites. In one arrangement of CoO6 octahedra there is the not too common face sharing to form infinite columns; in the other arrangement a zig-zag sheet, as far as we know differing from anything thus far reported, is formed by the sharing of edges and corners.

The analysis of closed circuit systems in which spontaneous steady-state electric currents appear can be carried out with the use of the function [function not transcribed]. The analysis indicates that any open circuit system of the form. Phase 1, barrier 1, phase 2, ......, phase b, barrier b, phase 1' is a chemical source of electromotive force when the phase 1 and 1' are identical, when the system contains two or more barriers whose sets of ionic transport members are different, and when the system is composed of two or more phases whose chemical properties are different. A general expression for the electromotive force of model systems composed of homogeneous phases and biological membranes in linear array can be written as [expression not transcribed] in which the indicated summations are to be performed for all barriers and for all ions to which each barrier is permeable.

In the analysis of the effect of ionizing radiation on living systems, the problem is complicated by the interaction of one part of the system with other parts. If an entire mouse is subjected to radiation, only a few of the most radiosensitive organs, the "weak links," react to the insult and essentially limit the size of the dose delivered since there is little to be learned from irradiating a dead mouse. Thus an insensitive organ like muscle will not respond at all to a total body dose. Likewise, every organ is composed of several different kinds of cells, and the most radiosensitive cells in the organ will determine the reaction observed.

Data on the mitotic indices of human bone marrow cells were reported in the first paper of this series, and theoretical considerations on the applicability and limitations of the index in determining kinetic parameters were discussed. In the present paper an attempt is made to compute time parameters of normal bone marrow cell proliferation from the data presented in the first paper.

Previous investigations that the pancreas is a radioresistant organ. Ivy in 1924 noted the presence of a fibrotic atrophic pancreas in a dog which had received one erythema dose to the epigastrium. Fisher in 1923 reported that four to five erythema doses delivered in a single application caused complete disappearance of the irradiated pancreatic remnant in about two months. These dogs died because of uncontrolled diabetes. One dog that received four erythema doses (possibly 200 r) was sacrificed after five months. At autopsy the irradiated pancreas had disappeared, but 275 mgm of regenerated pancreas were found at the base of the main duct and 100 mgm at the base of the accessory duct. Leven in 1933 implanted radon seeds into the pancreas. Dosages varied from 528 to 1584 millicurie hours. At postmorten the pancreas surrounding the seeds demonstrated fibrous atropy and foci of necrosis. The islets appeared normal but were relatively larger in size. Rauch in 1952 reported that dogs given 200 r in air over the pancreas on alternate days until a total of 1600 r was received failed to show any histological changes after two months. Lushbaugh and Spalding and Lushbaugh reported that over 1500 r of whole-body …

Our earlier in vitro studies have suggested that malignant tumors may not produce new cells more rapidly than normal cells are produced in the "steady state" equilibrium. Obviously tumors of all typed represent a diversion from "steady state" production with a net gain in mass of tissue. However, the increase in mass is not necessarily constant and may fluctuate in the natural history of the disorder. DNA labeling with tritiated thymidine had made it possible to characterize normal "steady state" hemopoietic growth parameters. We therefore thought it mandatory to extend these techniques to the study of growth rates of human leukemic cells. Also, since current therapy is more or less closely tied to a concept of unrestrained rapid growth, which we in part have begun to question, it appeared wise to look back at the historical development of knowledge about tumor growth. The existence of tumors in man has been known for millenia.

Numerous studies on the effects of radiation on the central nervous system used traditional pathomorphological changes as parameters of radiosensitivity, but pathogenesis and mechanisms of radiation injury to the nervous tissue are still little understood. Furthermore, the great discrepancy of dose requirement leading to physiological responses and on the other hand to pathomorphological changes in the central nervous system is not satisfactorily explained.

It has been known for many years that bone growth may be retarded by relatively large doses of therapeutic radiation. Similar doses of radiation have also shown retarded growth in animals. More recently, reports of studies of Japanese children exposed to the Atomic Bomb Detentions at Hiroshima and Nagasaki and Marshallese children exposed to radiation in the fallout accident of 1954 have indicated some impairment in their growth and development, possibly related to radiation exposure. Since the doses of radiation received by these children were lower than would be expected to produce retardation of bone growth by direct irradiation, it was considered that indirect mechanisms might play a part. This preliminary report summarizes investigations of possible indirect effects of X-irradiation in bone growth in rats.

Encysted Trichinella spiralis larvae incorporated carbon-14 from mice fed diets containing C14 -labeled glycerine and DL-alanine. In general, a higher level of C14 activity (C14 per gram of dry tissue) was found in muscle larvae than in muscle tissue. The presence of encysted Trichinella larvae in the muscles of 56-day and 180-day infected mice did not alter incorporation of C14 from these amino acids into infected muscle protein when compared with noninfected muscle. These experiments were extended to include the aromatic amino acids, DL-tyrosine and DL-tryptophan.

Seven lysogenic strains - three of Rhizobium Leguminosarum and four of R-trifolii - were identified among a total of 54 strains from these two species and R. phascoli. The R. leguminosarum strain may be multiply lysogenic; two of them also produce lethal agents resembling bacteriocins in their effects. Lysogeny was confirmed by standard criteria of UV-inducibility, self-immunity, and reproductive ability. Lysogenic conversion involving symbiotic characteristics was not observed. A minimum of six different temperate phage were identified. The host range includes strains of the above three rhizobial species, but not of R. mclilotii. Variation in host specificity of some phage following host passage is under investigation.

The following cells were operated at 820°C: [equations not transcribed] where the over-all reaction in each cell is simply the transfer of NaCl from pure NaCl to the mixtures of the right hand compartment. The porcelain acts as a pure sodium ion conductor in these cells. The relative partial molar free energy of mixing for sodium chloride, FMNaCl, is given by [equation not transcribed] where E is the EMF of the cell. Results are given over the entire composition range in each system and compared with previous measurements from other sources. Other thermodynamic quantities are calculated from the results. Experiments using a H2, HCl mixture in place of Cl2 are discussed, as well as the extension of the measurements to other systems.

Previous attempts by the present authors to compare the behavior of orally administered vitamin B12 with that of injected material have been inconclusive. Thus, 30 days after administration to normal humans, 0.19% of a tracer amount (0.5 μg) of injected radioactive vitamin B12 is excreted per day; and in an independent study, the eventual daily output was found to be 0.23% of a 3 μg dose. By contrast the total excretion rate of normal vitamin B12 from body stores appears to be only ≈0.03% per day. Such a divergence may result from incomplete mixing of radioactive vitamin B12 and body stores of the vitamin. Alternatively it may actually reflect the functioning of different compartments attending the several modes of administration involved. The possibility of degradation or transformation of vitamin within tissues and organs must also be considered.