The aim of this series of experiments was to evaluate the existence of abscopal effects of irradiation. No attempt was made towards the elucidation of mechanisms. Very early in the history of radiological research it was noticed radiation produces both local and general effects involving the entire body. Gauss and Lembcke introduced the term "Roentgenkater" (radiation sickness). They ascribed these "General Effects" to the circulation of toxic substances released from cells that disintegrated following irradiation.
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.
Two methods are proposed for calculating zero-point energies of molecules. The first makes use of the fact that one can easily write down the quantum mechanical Hamiltonian for a vibration system. The zero-point energy can then be obtained by a perturbation scheme without solving the secular equation. The second method requires a knowledge of the normal modes and frequencies of a reference molecule, but then enables one to calculate isotope effects by a perturbation scheme. The methods are applied to some examples and the convergence of the perturbation series is investigated. The approximate validity of the law of the mean for the isotope effect on zero-point energies is explored within the framework of the methods.
Since 1940 it has been known that extra salt (i.e. sodium chloride) facilitated the development of experimental hypertension induced by various sterols; subsequently hypertension was induced by desoxycorticosterone acetate plus sodium chloride; then hypertension was produced by using hypertonic saline as the sole source of liquid; and finally, in 1953, Menesly and his associates reported that chronic ingestion of excess dietary salt alone would produce hypertension in rats. Furthermore, in conformity with general pharmacologic experience relating dose response to successive increments of a drug, as the average daily salt intake increased, the average systolic, blood pressure increased.
Several methods of determining meteorite ages depend ages upon nuclides formed by cosmic ray interactions. The tactic assumption is always made that the intensity of cosmic radiation does not vary in time or space. However it is known that the intensity of cosmic radiation at the earth varies with the solar activity. The spectrum of cosmic ray protons and alpha particles exhibit a marked drop at the low energy end (<1.5 GeV) and the intensity in the region appears to follow the 11 year cycle of solar activity. The low energy cosmic rays increase in intensity with a decrease in solar activity. These changes in cosmic ray intensities are generally attributed to a modulation of the galactic cosmic radiation by the magnetic fields associated with the outward streaming solar material, the solar wind. One would therefore expect that the cosmic ray intensity several astronomical units from the sun is greater than the intensity at the earth's orbit, particularly at the low energy end of the spectrums.
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.
Radiation and annealing mechanisms for dimensional and c-axis changes in which the di-interstitial can be mobile at any or all temperatures above absolute zero are shown to be concordant with earlier work used to determine the migration energy energy of single interstitials and the absolute rate of displacing atoms in graphite. The mechanisms account for the stability of c-axis and dimensional changes with time in the absence of irradiation and with observed c-axis annealing at room temperature following irradiation at low temperatures.
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 gamma irradiation were required to produce histologic changes in alpha cells in 8 hours, and over 5000 r to produce changes in the beta cells in the same time. These changes had disappeared by 24 hours.
Kalanchoe seedlings were exposed to 330 r/20 hrs/day from a Co60 source. Samples were harvested weekly. No new leaves were produced after initial exposure to irradiation. Mitosis in the apical meristem appears to have been suppressed. However, the axillary meristem and the cambium continue their activity. This results in a much broadened stem tip with enlarged cells, supported by a stout internode in which cell size has remained relatively normal but cell number has increased. After about 26 days of exposure, meristematic activity in the shoot apex region appears to resume. This results in the formation of growth centers which can give rise to leaves or malformed structures. The original phyllotaxy is not recovered. It is suggested that this resumption of growth may be an instance of adaptation to irradiation.
This paper will first note briefly the place and status of radiobiotopical investigations with fast neutrons. The monoenergetic (fast) neutron technique employed at this laboratory will be then described and results of studies with various criteria-of-effect in the mouse will be reviewed. Finally, certain general patterns of response for these systems will be pointed out as functions of neutron energy.
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.
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.)
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.
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.
It has been established by chromosome marker studies, histochemical, immunological, and cytological methods that the hemopoietic tissues of animals exposed to lethal doses of whole-body irradiation can be repopulated by transfused autologous, homologous or heterologous bone marrow cells. However, the morphology of the cell responsible for the regeneration of hematopoietic activity in the various hemopoietic organs has not been identified. It has been shown that the bone marrow contains the cell or cells capable of regenerating all types of hemopoietic tissues. In order to identify transfused cells, one must have a label which persists through successive divisions. Odell and Smith labeled the donors with S35 methionin and were thus able to follow the accumulation of the donor marrow cells in the recipients lungs and subsequently their releases to the bone marrow and spleen. However, this compound has a relatively rapid turnover in the labeled cells and thus a relatively limited capability of serial studies to observe mitosis and differentiation. Tritiated thymidine is ideal for this purpose since it is incorporated solely into DNA and is diluted only by mitosis. In addition the high resolution with tritium makes it certain that one is observing nuclear labeling. Bond et al. have studied the migration of labeled cells from a non-irradiated parabiotic rat to the irradiated member. Nagal and Knisely have studied the fate of in vitro labeled autologous and homologous bone marrow cells after transfusion into two patients. Balner et al have labeled bone marrow cells in vivo with H3TDR and transfused these labeled cells into irradiated homologous newborn mice and studied their distribution as a function of time following transfusion by [unintelligible] of autoradiography.
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.
Electron-transfer reactions involving bridged transition states are examined from the point of view of adiabatic electron transfer theory. One important function of the bridging group is to decrease the effective dipole moment of the charge system of the reaction ions. The effect on the activation energy is different for outer-sphere and inner-sphere reactions. Trends in the halide and hydroxide catalysis of isotopic exchange reactions of transition metal ions are discussed.
Since the end of the last century (Tarknow, 1896) radiation effect o the nervous tissue has been studied in experimental animals and humans by numerous investigators, using mostly pathomorphological changes as a parameter of radiosensitivity . With increasing time intervals following radiation, pathomorphological changes are more evident, which has been known for quite some time.
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.
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.
Production cross sections and angular distributions of Λ and K° particles produced by 11.4 Bev/c π" mesons in hydrogen have been measured. A systematic investigation was made of all two-body decays of unstable neutral particles. No events inconsistent with γ, Λ, or K° were found. Production cross sections, angular distributions and effective mass distributions of π mesons produced in 4-prong events were also measured. No evidence for dominance of any high mass multi-pion resonance was found. Both the pion production and strange particle production reactions demonstrated peripheral characteristics in that the baryon was strongly peaked backward in the center of mass. The average transverse momentum was observed to be a monotonically increasing function of mass. The experimental total interaction cross section was 25.3 ± 1.5 mb. The effect of the pion-nucleon T ' 3/2 isobar was clearly observed.
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%.
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 mode of dissolution of magnesium in molten magnesium chloride contacted with Mg-Pb alloys was studied at 750°C using anodic chronopotentiometry. An inert tantalum anode was used to determine relative amounts of magnesium dissolved in its chloride as a function of magnesium activity in the alloy. According to the law of mass action a linear dependence of magnesium solubility on a Mg indicates Mg2Cl2 as the reaction product and a parabolic dependence indicates MgCl. It was found that the amount of magnesium dissolved in its chloride was directly proportional to the magnesium activity in the metal phase, i.e., a linear dependence, indicating Mg2Cl2 as the subhalide species. Due to the corrosive nature of the Mg-MgCl2 system a special apparatus was used so that only the inert metals tantalum and molybdenum came in contact with the melt. Purification procedures and conditions for proper equilibration and measurement were established and are reported. The basic equation of chronopotentiometry, [equation not transcribed], was found to hold and at given magnesium activities the product [unintelligible] did not vary with the current, indicating the validity of the analytical technique.
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.
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.
Tritiated thymidine (H3TDR), a specific precursor of deoxyribonucleic acid (DNA), has proved to be a valuable tool in the study of in vivo cellular kinetics. Various methods of analysis have been used in autoradiographic investigations of proliferative patterns and time parameters in different cell lines.
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.
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.
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.
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 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.
In the summer of 1960 one of the little used wells on the Brookhaven National Laboratory site became accidentally contaminated with radioactive material. The contamination was discovered during a routine sampling of all wells in the waste disposal area, so there was a period of several weeks between the time of discharge.
The problem to be discussed originates in our interest in the diagnosis and treatment of brain tumors. It has been established by others that some positron-emitting radioactive isotopes, in particular Arsenic-74 and Copper-64, can be causal to localize in brain tumors and thus to serve as agents for locating the tumors. Although other kinds of radioisotopes have also been used successfully in locating tumors, positron emitters have some especially attractive features. Their use is based on the principle that a positron, or positively charged electron, is a form of "anti-matter," and when it encounters an ordinary negatively charged electron both are annihilated, giving rise to two gamma rays that are emitted in opposite directions. Such an event is detectable through the use of coincidence counting. The data for which the method of analysis is to be discussed in the present paper is generated by a device using the coincidence counting method with multiple detectors in an arrangement potentially suitable for three-dimensional localization of brain tumors.
The transition from dormancy to growth in plant seeds has been the topic of many biological studies (1,2). Of particular interest to the radiobiologist are the dramatic changes in radiosensitivity occurring soon after the soaking of the seeds (3). These changes are thought to be associated with the commencement of proliferative activity. The recently developed method of labeling DNA with tritiated thymidine allows analysis of proliferative activity in greater detail than was heretofore possible. In the present study, uptake of tritiated thymidine and mitotic counts were used to determine the sequence of activation of proliferation in tissues or organs of the germinating corn embryo.
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.
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