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Cosmic Ray Produced Ar37 and Ar39 Activities in Recently Fallen Meteorites

Description: 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… more
Date: February 1, 1968
Creator: Davis, R. Jr.; Stoenner, R. W. & Schaeffer, O. A.
open access

The Mg-MgCl2 System — A Chronopotentiometric Study

Description: 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 amou… more
Date: February 1, 1968
Creator: Van Norman, John D. & Egan, James J.
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Improved Growth of Etiolated Pisum Seedlings for Bioessays by the Use of a Complete Chelated Nutrient Solution

Description: Tissue from etiolated or partially etiolated Pisum seedlings is widely used in work on growth substances and light responses. However, in the authors' experience growth under the conditions commonly employed is frequently irregular, and often affords little or no satisfactory experimental material. Although the literature records little evidence of such difficulties, personal communication with many investigators leaves no doubt they are widespread.
Date: October 1, 1963
Creator: Hillman, William S. & Puruya, Masaki
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Total Cross Sections for K Mesons and π Mesons on Protons and Deuterons between 2.5 and 6 BeV/c

Description: Recent measurements of the pion-proton total cross section, taken with small statistical errors, have shown the existence of two new maxima in the momentum range between 2 and 3 BeV/c. Measurements of comparable statistical accuracy, covering the momentum range from 2.5 to 8 BeV/c are reported in the present paper. In addition to the total cross sections for π± mesons on protons, their total cross sections on deuterons have also been determined. Some data were also taken on the total cross sect… more
Date: October 1, 1963
Creator: Baker, W. F.; Jenkins, E. W.; Kycia, T. F.; Phillips, R. H.; Read, A. L.; Riley, K. F. et al.
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Transport, Homeostasis and Specificity in Trace Metal Metabolism

Description: A working definition of homeostasis is the following: the sum total of the processes which maintain a steady level of various substances or functions within a living baby. Our own concern will be with the homeostasis of trace metals. I will begin with a slide which shows the total body concentration of various metals, including "trace" ones. Only metallic constituents which play a role in the maintenance of the body's structure and function are shown. The essential trace metals among them are r… more
Date: October 1, 1963
Creator: Cotszias, George C.
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Abscopal Effects of Localized Irradiation by Accelerator Beams

Description: 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 f… more
Date: February 1, 1963
Creator: Jansen, C. R.; Bond, V. P.; Rai, K. R. & Lippincott, S. W.
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Chronic Excess Salt Consumption as an Etiologic Factor in Human Hypertension

Description: 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 conf… more
Date: February 1, 1963
Creator: Dahl, Lewis K.
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Di-Interstitial Annealing During the First Neutron Irradiation of Graphite: The Mobility of C2

Description: 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… more
Date: February 1, 1963
Creator: Schweitzer, Donals G.
open access

The Effects of 250-kv X-Ray on the Dog's Pancreas: Morphological and Functional Changes

Description: 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 sacrifice… more
Date: February 1, 1963
Creator: Archamefau, John; Griem, Melvin & Harper, Paul
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The Effects of Chronic Gamma Irradiation on the Growth of Kalanchoe cv. "Brilliant Star"

Description: 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 da… more
Date: February 1, 1963
Creator: Stein, O. L. & Sparrow, A. H.
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The Effects of Radiations of Different let on Early Responses in the Mammal

Description: 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.
Date: February 1, 1963
Creator: Bateman, J. L. & Bond, V. P.
open access

Effects of Trichinella Spiralis Infection on Incorporation of Amino Acids into Serum and Hemoglobin

Description: 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 ext… more
Date: February 1, 1963
Creator: Hankes, Lawrence V. & Stone, Richard D.
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Elimination of Phases the Life Cycle of Leukemic Cells From in Vivo Labeling in Human Beings With Tritiated Thymidine

Description: 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 stat… more
Date: February 1, 1963
Creator: Killmann, S. A.; Cronkite, E. P.; Robertson, J. S.; Fliedner, T. M. & Bond, V. P.
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The Fate of Transfused H3 Thymidine Labeled Bone Marrow Cells in Irradiated Recipients

Description: 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… more
Date: February 1, 1963
Creator: Fliedner, T. M.; Thomas, E. D.; Meyer, L. M. & Cronkite, E. P.
open access

The Function of Bridging Groups in Electron-Transfer Reactions

Description: 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.
Date: February 1, 1963
Creator: Hush, N. S.
open access

Fundamental Problem of Late Neurological EffectFollowing Acute Irradiation

Description: 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.
Date: February 1, 1963
Creator: Yamamoto, Y. L.
open access

Indirect Effect of X-Radiation on Bone Growth in Rats

Description: 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… more
Date: February 1, 1963
Creator: Conard, R. A.
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Inelastic Interactions of 11.4 Bec/c π" Mesons in Hydrogen

Description: 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. Bo… more
Date: February 1, 1963
Creator: Ferbel, T. & Taft, H.
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Lysogeny in Rhizobium Leguminosarum and R. Trifolii

Description: 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 s… more
Date: February 1, 1963
Creator: Schwinghamer, E. A. & Reinhardt, D. J.
open access

The Microbeam as a Tool in Radiobiology

Description: 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. Like… more
Date: February 1, 1963
Creator: Curtis, Howard J.
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Mitotic Indices of Human Bone Marrow Cells. Duration of Some Phases of Erythrocytic and Granulocytic Proliferation Computed From Mitotic Indices

Description: 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.
Date: February 1, 1963
Creator: Killmann, S. A.; Cronkite, E. P.; Fliedner, T. M. & Bond, V. P.
open access

Possibilities and Limitations in the use of Tritiated Thymidine for in Vivo Cytokinetic Studies on Lymphoreticular Tissue

Description: 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.
Date: February 1, 1963
Creator: Cottier, H.; Odartchenko, N.; Feinendegen, L. E. & Bond, V. P.
open access

Radiation Effect on the RNA Metabolism of the Central Nervous System

Description: 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.
Date: February 1, 1963
Creator: Yamamoto, Y. L.; Feinendegen, L. E. & Bond, V. P.
open access

Thermodynamics of Fused Salt Mixtures From EMF Measurements. The Systems NaCl-KCl, NaCl-MgCl2, and NaCl-CeCl3.

Description: 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 compare… more
Date: February 1, 1963
Creator: Egan, James J. & Bracker, John
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