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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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Cosmic Rays From Large Supernovae

Description: The theory of the hydrodynamic origin of cosmic rays proposed by Johnson and the author (Colgate) has developed to the point where the final evolution of a star to the supernova instability and subsequent explosion can be described with sufficient detail such that cosmic rays with appropriate intensity, composition, and spectrum to account for observations are a logical and necessary result. In the first publication it was pointed out that nuclei in the surface of the star may acquire many orde… more
Date: October 21, 1963
Creator: Colgate, S. A. & White, R. H.
Item Type: Refine your search to only Report
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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
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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Effects of Chronic Excess Salt Ingestion: Possible Implications of the Accelerated Induction of Experimental Hypertension by 2,4-Dinitrophenol

Description: Recently, we reported that the administration of the thyroid hormone, L-triiodothyronine (T3), markedly accelerated the development of experimental hypertension associated with a high-salt intake in intact rate. Earlier, Selye and his associates and Masson, Corcoran, and Page has observed a similar effect from thyroxin in uninephrectomized salt-fed rats. We were aware of the fact that oxidative phosphorylation is uncoupled by the thyroid hormone and were intrigued by the possibility that such u… more
Date: October 14, 1963
Creator: Dahl, Lewis K.; Heine, Martha & Tassinari, Lorraine
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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
Item Type: Refine your search to only Report
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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
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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An Investigation of the Low Frequency Motions in Isotactic and Atactic Polypropylene by Neutron Inelastic Scattering

Description: The vibrational spectra between 1000 and 30 cm-1, derived from measurements of the inelastic scattering of "cold" neutrons, are presented for isotactic polypropylene at samples temperatures below and above both the glass transition and the melting point. A tentative assignment of the observed modes is suggested by comparison with recent calculations by Miyazawa, Ideguchi, and Fukushima of the optically active phases of the fundamental vibrations for an isotactic helical polypropylene chain and … more
Date: October 14, 1963
Creator: Safford, G. J.; Danner, H. R. & Boutin, H.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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On the Crystal Chemistry of Salt Hydrates, III. The Determination of the Crystal Structure of FeSO4·7H2O (Melanterite)*

Description: Monoclinic FeSO4·7H2O is the stable solid phase between -1.82° and 56.6° C in contact with a saturated water solution of FeSO4. It occurs in nature as an oxidation product of Fe-containing sulfides an is called melanterite. FeSO4·7H2O belongs to a series of compounds Me2+SO4·nH2O, where Mn2+ is a cation with an approximate ionic radius of 0.7Å. The 1-, 4- and 5-hydrates are known to crystalize each in only one form, whereas the hexa- and the heptahydrates occur both in two different forms. The … more
Date: October 15, 1963
Creator: Baur, Werner H.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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