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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 of alleles according to bristle patters had its counterpart in a similar arrangement of portions of the achaete-scute gene locus. On this assumption they divided the locus into twelve elementary subunits. It was assumed that each allele arose by a change involving a certain combination of these centres. According to their theory, the achaete-scute locus is made up of separate, regularly spaced, and linearly arranged functional units. Several years later, Oliver described the occurrence of crossing over between two alleles of the "lozenge" locus. Then Green and a number of other workers analyzed similar phenomena in different regions of Drosophila chromosome. During the same period Lewis developed the theory of pseudoallelism, which interprets the occurrence of recombinants in interallelic crosses as the result of gene duplications. Thus for more than three decades evidence has gradually been building up to indicate that the gene might not be the basic unit of recombination; but until recently it did not serve to convince the large majority of those interested in genic composition.
Date: October 14, 1963
Creator: Demerec, M.
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 uniform random (or pseudo-random) sequences.
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 when the reaction was carried out for 12 hrs. in a refluxing benzene solution. The degradation method used is outlined in Fig. 1. The view that the reaction in intramolecular is supported by the following facts: (1) The inactive benzene used in the solvent experiments was devoid of activity at the end of a run within the precision of our assay methods. A rearrangement carried out with inactive diphenyl in benzene-1-C- 14 yielded diphenul having an activity indicating less than 0.001% intermolecularity.
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 in these collisions. Some of these such as elastic scattering, pion production, and associated production of hyperons and K-mesons have analogues in p-p collisions. The similarities and differences between the p-p and p-p results can usually be understood in a qualitative way and in some cases quantitative comparison with theory has been possible. The annihilation reactions leading to final states containing pions alone or pions with K-mesons are unique to the nucleon-antinucleon system as are the reactions in which a hyperon, anti-hyperon pair is produced. In the following, we report the principal characteristics of proton-antiproton reactions. Although the scope of this paper is comprehensive it is not a definitive report of the experiment as much of the work is still in progress.
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 theoretically, including the possibility of anisotropy in the leakage probability.
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 ATP (3) thus supporting the original idea that the ATP to ADP transformation is related to the globular to fibrous transformation of the actin protein itself. Mommaerts was the first to show that the ADP formed during polymerization remains bound to F-actin and Ulbrecht et al. while extending Mommaert's finding on exhaustively purified actin preparations have shown that the P1 formed during polymerization is not bound to F-actin. The stoichiometry of the splitting and the tightness of binding of the ADP lead inevitably to questions in regard to the position of bond breaking during the hydrolysis and to the nature of the forces involved in the tight binding of ADP to F-actin. To aid in the clarification of these problems, this study using O18 isotope was initiated.
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. Anisotropic temperature parameters were also determined for all atoms in the least squares analysis of the structure. The magnetic structure of CuSO4 has been determined in a continuation of a study started at Brookhaven in collaboration with Dr. P.J. Brown. Using the Wollan-Koehler-Bertaut notation, the antiferromagnetic spin ordering mode in the orthorhombic Pbnm cell is Ax, with the spin axis parallel to a. A moment of approximately 1 μB was found for the Cu2_ ion. The crystal structure of BaNiO2 was re-examined in a neutron powder diffraction study, and it was found that the earlier x-ray study of Lander is essentially correct. An alternative oxygen arrangement, for which x-rays would not have been very sensitive, had been suspected. BaNiO2 was also investigated for magnetic order at 4.2°K but conclusive results have not been obtained. A magnetic transition has been found in Fe2SiO4 in the neighborhood of 30°K. This compound has an olivine type structure with eight Fe2+ ions in the 4(a) and 4(c) positions of the Pbnm space group. Analysis of the magnetic structure is still in progress, but some preliminary results are discussed.
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 of manganese (III) with iron (II) and with various substituted iron (II)-phenanthroline complexes and to the reaction of cobalt (III) with manganese (II) in perchloric acid leads to an estimate of about 10 -4 F -1 sec -1 for the rate constant of the manganese (II)-manganese (III) electron exchange reaction at 25.0°. Attempts to determine the rate constant for this exchange by a radioactive tracer method were unsuccessful.
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 toward making this Congress a strikingly successful gathering.
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 responsible.
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 better if the pathologist, who must study pertinent material, restricts himself humbly to the recording of his observations, refraining from any attempt at interpretation. On the other hand, since seemingly audacious speculation has borne fruit in the past and the value of the information that results, if the speculation proves to be correct, is worth many times the effort, there is obvious justification for a thesis on the mechanism of delayed radionecrosis.
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 emulsion stack, the liquid hydrogen bubble chamber and the spark chamber. Counters provide immediate information but it is of a yes-or-no character, whereas the other methods are capable of actually mapping, with varying degrees of accuracy, an interaction between particles. The emulsion stack is quite familiar and need be discussed only briefly. Since individual silver halide crystals are rendered developable along the paths of charged particles, a sensitive detector may be built up with thick layers of specially sensitized emulsion having no base support. As the path of the particle may be through several emulsion having no base support. as the path of the particle may be through several emulsion layers and the track must be measured under a microscope, it is important to make each layer as thick as possible to lessen the problem of following the tracks from layer to layer. The usual compromise between the problems of scanning and those of processing these thick pellicles is to use emulsion slabs of 400 to 600 μ in thickness. As a 400 μ pellicle swells to over 1600 microns during processing and dries down to about 200 μ, due to the removal of the undeveloped silver halide, the technique is subject to severe overall and local distortions which limit its usefulness.
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 experimental techniques are refined. This use of increased momentum means that larger areas are required for the apparatus and that more power is necessary for the magnetic optics. All beam-sharing at the AGS is done by multiple use of each accelerated pulse because our experience indicates that pulse-by-pulse beam-sharing is relatively inefficient. (Expansion chambers have seldom been used at the AGS.) The problems of scheduling experiments becomes increasingly complex since combinations must be found satisfying the criteria: maximum number of experiments to run simultaneously; minimum downtime to be taken for rearrangement between successive experimental arrays
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 contention that loss of genetic materials following such fragmentation is a factor of a major importance in radiation-induced lethality and growth inhibition in plants.
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 that clinical consequences of radiation injury are similar to those with which the clinician has to deal with every day in the treatment of neoplastic disorders and its complications. Soon after the discovery of x-rays by Roentgen and of the phenomenon of radioactivity by Bequerrel in the last decade of the last decade of the 19th century, it was found that ionizing radiation can produce marked biological effects by interfering with cell- and organ functions. Senn and Hussey were the first to effectively treat leukemia by this means. This, since about 60 years, ionizing radiation has been a powerful tool in the hands of physicians both in diagnostic procedures and for therapy of malignant disease. It should not be forgotten however, that the price paid for this contribution of outstanding importance was high. Long before any nuclear weapons were used, a long list of fatalities and injuries among physicians, investigators, technicians and nurses, witnessed the possible consequences of radiation exposure. However, the number of lives saved through the use of ionizing radiation exceed greatly the number of lives ever lost through the harmful effects of radiation.
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 not overcome with the labeling of proliferating cells after tritiated thymidine injection in vivo if subsequent observation is limited to the rate of progression into mitosis of labeled cells that incorporated the tracer during the period of DNA-synthesis. Observation of separate mitotic phases, however, offers the possibility of following the progression of the wave of labeled cells at successive, short-lasting checking steps, and to analyze the variability in the times of passage through mitosis. In the present work, the progression of labeled cells as a function of time, after a single injection of tritiated thymidine, was followed in successive phases of mitosis in erythroblasts of dog bone marrow.
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 represented by black bars. Iron is both black and white. Indeed, if one excludes the fixed sequestered iron of myoglobin and of hemoglobin, one is left with a trace fraction of iron about which I will be talking later on. Note that the scale is logarithmic, indicating that the concentrations of essential metals in the body fall off sharply and smoothly.
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 sections for K+ mesons on protons and deuterons and for K- mesons on protons.
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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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
Partner: UNT Libraries Government Documents Department
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Transistorized 10-Mc Decade Scaler

Description: This scaler was designed to replace an obsolescent tube design that was in general use at Lawrence Radiation Laboratory in Livermore. The new design, using solid state devices and printed circuit modules, allows two complete scalers in one frame to occupy the same rack space as the tube design. Switches in the input circuits of the new scaler change input impedance and sensitivity for operation with either tube or transistor circuits. The use of transistors has greatly increased reliability, and has also reduced power by a factor of fifteen. Modular construction of all circuits, including the power supply, minimizes down time since all modules are replaceable without removing the scaler from its rack. Reliability, then cost, were the criteria dictating choice of components and circuits in the scaler design.
Date: October 24, 1963
Creator: Van Den Heuvel, C. A.
Partner: UNT Libraries Government Documents Department
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