Technical Report Archive & Image Library (TRAIL) - 12,573 Matching Results

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The Effect of Mitotic Cycle Duration on Chromosome Breakage in Meristematic Cells of Pisum Sativum

Description: One of the more apparent differences between acute and chronic irradiation is that exposure in the former is generally confined to a small fraction of a single mitotic cycle while in the latter; exposure of mitotically active tissue usually involves at least several cycles. Because of this difference, the number of cells in each stage of interphase would be of primary importance in acute radiation experiments since radiosensitivity is not the same in the G1, S and G2 periods. The duration of th… more
Date: October 14, 1963
Creator: Van't Hof, J. & Sparrow, A. H.
Partner: UNT Libraries Government Documents Department
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Gene Structure: Genetic Fine Structure. Remarks.

Description: Though only recently established, this concept has been developing for a long time. More than thirty years ago Dubinin, Serebrovsky, and other, investigating the phenotypes of a number of "achaete-scute" alleles of Drosophilia melanogaster, found that the alleles could be arranged in a definite series accoding to bristle patters, and also that the heterozygotes lacked only those bristles which were affected in common by both participating alleles. They concluded that the serial classification o… more
Date: October 14, 1963
Creator: Demerec, M.
Partner: UNT Libraries Government Documents Department
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The "N" on "P" Silicon Solar Cell Gamma Ray Dose Rate Meter

Description: The recently developed "n" on "p" type silicon solar cell has been evaluated for application as a high-level gamma radiation dose rate meter. The solar cell ionization current was found to be a linear function of dose rate in a range 10 2 to 10 7 rads per hour. A degradation rate of approximately one per cent per megarad was measured after stabilization with twenty megarads of cobalt-60 gamma radiation. The system has proven to be stable over long periods of time. Temperature dependence correct… more
Date: November 18, 1963
Creator: Mueller, A. C.; Rizzo, P. X. & Galanter, L.
Partner: UNT Libraries Government Documents Department
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On the Generation of an Arbitrarily Autocorrelated Sequence of Random Variables from a Sequence of Independent Random Numbers

Description: For a wide range of statistical experiments, we require a sequence of random variables [unintelligible], which have prescribed mean values μn and variances σn2, with a given autocorrelation ρt. The [unintelligible] are to be generated as a sequence of real functions of independent random numbers [unintelligible], each of which is uniformly distributed in. The reason for this choice of specification for the [unintelligible] is that most computers have standard subroutines which generate such uni… more
Date: October 15, 1963
Creator: Halton, John H.
Partner: UNT Libraries Government Documents Department
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Preparation and Some Properties of Krypton Difluoride

Description: The compound KrF4 was prepared by Grosse et al. by passing an electric discharge through the elements at -196°C. Evidence for formation of KrF2 has been obtained by Pimental and Turner by UV irradiation of the elements frozen into an inert gas matrix at 20°K. Using an electron beam to irradiate krypton and fluorine at -150°C, we have prepared KrF2 in 100mg amounts and examined some of its properties.
Date: October 15, 1963
Creator: Mackenzie, D. R.
Partner: UNT Libraries Government Documents Department
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The Rearrangement of Diphenyl

Description: We wish to report unequivocal evidence for the water promoted, aluminum chloride induced intramolecular rearrangement of the benzene rings in diphenyl. When diphenyl 1→1,1'-C14, prepared in 80% yield via an Ullmann reaction on iodobenzene-1-C1 14, was heated to 100° for 30 min. with 10 mole % of aluminum chloride and 1 mole % of water, the radioactivity, originally localized at the two connecting carbons had been randomly distributed. Recovered active diphenyl was also shown to be randomized wh… more
Date: October 15, 1963
Creator: Wynberg, Hans & Wolf, A. P.
Partner: UNT Libraries Government Documents Department
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Interactions of High Energy Antiprotons in Hydrogen

Description: In the fall of 1961 an extensive program of investigation of high energy p-p interactions was begun at the Brookhaven AGS. The BNL 20" liquid hydrogen bubble chamber and an electrostatically separated beam were used to obtain a total (to date) of 300,000 exposure with about 15 antiprotons per pulse. The exposures were made at antiproton momenta of 3.25 Bev/c and 3.69 Bev/c in the laboratory. Approximately 80% of the exposures were made 3.69 Bev/c antiprotons. A wide variety of reactions occur i… more
Date: October 15, 1963
Creator: Baltay, C.; Ferbel, T.; Sandweiss, J.; Taft, H. D.; Culwick, B. B.; Fowler, W. B. et al.
Partner: UNT Libraries Government Documents Department
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Some Problems in the Interpretation of Exponential Experiments

Description: Buckling measurements at BNL have employed two experimental methods which in principle should yield identical results but in practice show a systematic and significant discrepancy. In this paper the experimental evidence of these errors is reviewed and their source is traced by means of theory to the radial flux transients which perturb the asymptotic neutron spectrum in the exponential assemblies. Some alternate and apparently more precise methods of analyzing the data are examined theoretical… more
Date: October 15, 1963
Creator: Hellens, Robert L. & Andersen, Eigil
Partner: UNT Libraries Government Documents Department
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Adenosinetriphosphate Cleavage During the G-Actin to F-Actin Transformation and the Binding of Adenosinetriphosphate to F-Actin

Description: Since the discovery of the Straub and Feuer as well as Laki et al. that ATP bound to G-actin is transformed to ADP and inorganic phosphate during polymerization of actin (1, 2), it has become increasingly clear that the chemical changes in the nucleotide are related to the change in the physical state of the protein. Barany, Biro, Molnar and Straub have shown that highly purified actin preparation free of any enzyme which would use ATP, ADP or AMP as a substrate still catalyze the breakdown of … more
Date: October 15, 1963
Creator: Barany, M.; Koshland, D. E., Jr.; Springhorn, S. S.; Finkleman, F. & Theratil-Anthony, T.
Partner: UNT Libraries Government Documents Department
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Neutron Diffraction Studies at the Puerto Rico Nuclear Center

Description: A neutron diffraction program was initiated recently at the Puerto Rico Nuclear Center. The two double crystal spectrometers in use were assembled with the aid of staff members of the Brookhaven National Laboratory. The first research problem to be completed was a single crystal structure analysis of CaWO4. Choosing the origin at the 4(a) tungsten site in the tetragonal I41/a cell. the 16(f) oxygen parameters were found to be as follows: x=0.2413 ± 0.0005, y=0.1511 ± 0.0006, z=0.0861 ± 0.0001.… more
Date: October 15, 1963
Creator: Almodovar, I; Bielen, H. J. & Frazer, B. C.
Partner: UNT Libraries Government Documents Department
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The Kinetics of Some Oxidation-Reduction Reactions Involving Manganese (III)

Description: The kinetics of several oxidation-reduction reactions involving manganese (III) have been studied spectrophotometrically by the use of a flow technique. The free energies of activation for the oxidation of various substituted tris-(1,10-phenanthroline) complexes of iron (II) by manganese (III) in perchloric acid and in pyrophosphoric-sulfuric acid media were found to be linearly related to the standard free energy changes of the reactions. The application of the Marcus theory to the reactions o… more
Date: October 15, 1963
Creator: Diebler, H. & Sutin, N.
Partner: UNT Libraries Government Documents Department
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Problems of Present Day Genetics

Description: At this, the XI International Congress of Genetics, the major portion of the program has been devoted to synopsis, in which outstanding problems of modern genetics have been discussed. It required vision on the part of the Organizing Committee to conceive such a program for an international congress; and it required courage, a great deal courage, to schedule 25 symposium on a 6 meeting days. But the vision and courage have been amply rewarded. The symposia were outstanding, and have contributed… more
Date: October 15, 1963
Creator: Demerec, M.
Partner: UNT Libraries Government Documents Department
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Organization of Genetic Material in Salmonella

Description: Evidence is rapidly accumulating that the genetic material carried in a chromosome is arranged in a highly organized manner. The nucleotides of DNA constituting a gene are grouped in sequence, like the letters of a word, and presumably each word uniformly consists of three letters. Successive words make up a sentence containing the information needed to build a protein molecule. Each word of the sentence is transcribed to form an amino acid of the protein for which the particular gene is respon… more
Date: October 15, 1963
Creator: Demerec, M.
Partner: UNT Libraries Government Documents Department
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Cytochemistry of Delayed Radionecrosis of the Murine Spinal Cord

Description: In the vast field of radiation pathology we find pathologists, anatomists, and even physiologists busily at work, but the radiobiologist is conspicuously absent, although, according to Zirkle (1959), this field is clearly within his domain. Perhaps it is wise to take this broad hint of the scientifically so well equipped radiobiologist and to stay clear from an area in which an incalculable array of variables makes clearcut experimentation a hopeless venture, a priori. Perhaps it would be bette… more
Date: October 15, 1963
Creator: Zeman, Wolfgang
Partner: UNT Libraries Government Documents Department
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The Photogrammetry of the Tracks of Elementary Particles in Bubble Chambers

Description: In high-energy particle physics the initial problem is to obtain information about the behavior of particles which are invisible by any known means (the radius of a proton is 10-13 cm) and which may be traveling at speeds greater than 180,000 miles per second, but at less than the speed of light. Some of the work is being done with the use of electronic counters, but the larger fraction is currently done by three techniques which employ the photographic process. These are the silver halide emul… more
Date: October 15, 1963
Creator: Garfield, John F.
Partner: UNT Libraries Government Documents Department
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Method for Comparing Small AC Voltages in the Presence of Large DC Components

Description: A feedback technique has been developed to equalize the DC levels of two signal sources so that AC signal components which are much smaller than the DC levels can be compared accurately without introducing a low frequency cut-off and consequent rate-dependency into the system. A digital integrator in the feedback loop provides a highly stable long-term "memory" so that the correct level will be maintained during intervals when the signals are "frozen" at some arbitrary point.
Date: October 15, 1963
Creator: Rogers, E. J.
Partner: UNT Libraries Government Documents Department
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On the Crystal Chemistry of Salt Hydrates, II. A Neutron Diffraction Study of MgSO4·4H2O

Description: The crystal structure of MgSO4·4H2O has been refined using single crystal neutron diffraction data for the three main zones. The hydrogen positions which were found are essentially those which have been deduced from X-ray data in an earlier investigation.The mean value of the O-H bond lengths is 0.97Å. The O-H-O bonds are bent considerably. One hydrogen atom does not participate in hydrogen bonding, as can be concluded from the geometry of its surroundings and its thermal motion.
Date: October 15, 1963
Creator: Baur, Werner H.
Partner: UNT Libraries Government Documents Department
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AGS Performance and Plans

Description: The scope of the AGS complex has expanded rapidly during the three years since an accelerated beam was first obtained. Demand for research time far exceeds the amount available although facilities have been much increased. At the same time, experiments are being designed which are more complicated than previous ones and which make more stringent demands on the accelerator and on its auxiliary equipment. There is a continuous trend of experiments to particle beams of greater momentum, as the exp… more
Date: October 15, 1963
Creator: Green, G. K.
Partner: UNT Libraries Government Documents Department
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Magnetic Structure of Binary Fluorides Containing Mn2+

Description: Binary fluorides of the type XMnF3 (X= Na, Rb, Cs, and NH4), which were investigated previously by means of x-ray, electron spin resonance specific heat, and magnetization measurements, have been reported to be antiferromagnetic. The present study reports powder neutron diffraction measurements on these compounds undertaken to confirm the antiferromagnetism and to study details of the magnetic ordering. Some information was also obtained concerning the nuclear structures.
Date: October 15, 1963
Creator: Pickart, S. J. & Alperin H. A.
Partner: UNT Libraries Government Documents Department
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The Influence of the Centromere of Chromosome Fragment Frequency Under Chronic Irradiation

Description: Studies on a large variety of plant species, particularly by Sparrow and his colleagues, have shown that radiosensitivity, as measured by growth inhibition and lethality, is strongly correlated with various parameters of the cell nucleus. Foremost among these are nuclear volume, SNA content and chromosome number. It is generally accepted that in proliferating cell systems chromosome damage may well be the principal radiobiological lesion, and the observed correlations are in line with the conte… more
Date: October 15, 1963
Creator: Evans, H. J. & Pond, Virginia
Partner: UNT Libraries Government Documents Department
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Hematological Effects of Whole Body Irradiation

Description: The development of nuclear arms added the effects of ionizing radiation to the direct and indirect mechanical, chemical or thermal hazards of "conventional" weapons. The biological effects of ionizing radiation are the result of absorption of energy and the morphologically recognizable damage is poorly understood. Although new in their use in weapons and difficult to evaluate in their consequences, ionizing radiations are by no means new to physicians. Furthermore, medical experience has shown … more
Date: October 15, 1963
Creator: Fliedner, T. M. & Cronkite, E. P.
Partner: UNT Libraries Government Documents Department
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Evaluation of Mitotic Time in Vivo, Using Tritiated Thymidine as a Cell Marker: Successive Labeling with Time of Separate MItotic Phases

Description: The duration of mitosis is of great importance in an evaluation of growth rates in proliferating somatic tissues, since calculations are based on observations of mitotic activity, and therefore final results are directly proportional to an assumed value for mitotic time. This duration cannot be measured directly in vivo at a tissue level, since the mode of distribution of the single cell value is not known. This difficulty is not overcome in extrapolations from in vitro measurements. Also it is… more
Date: October 15, 1963
Creator: Odartchenko, N.; Cottier, H.; Feinendegen, L. E. & Bond, V. P.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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