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in publisher: "Rochester Univ., NY USA"

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Nuclear structure theory. Annual technical progress report, October 1, 1979-August 31, 1980. [Univ. of Rochester]

This report summarizes progress during the past year in the following areas of nuclear structure and reaction theory: statistical spectroscopy (including random matrix methods, with applications to fluctuations in spectra and in strength distributions, and to problems of ergodicity; group symmetries in spectral-distribution theory; electromagnetic and ..beta.. transitions); meson scattering and absorption by nuclei (including general scattering theory with absorption, multiple scattering theory… more

Date: January 1, 1980

Creator: French, J. B. & Koltun, D. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Radiation induced asymmetries in mitotic recombination: evidence for a directional bias in the formation of asymmetric hybrid DNA in yeast

We have examined radiation-induced mitotic recombination using two alleles (his1-36, his1-49) in the his1 gene. When the haploid containing his1-36 is irradiated with varying doses of ..gamma.. rays and then mated with the unirradiated strain containing his1-49, analyses of the selected prototrophs show them to be primarily + +/+ 49. If, on the other hand, the haploid strain containing his1-49 is the irradiated parent, the prototrophic diploids are primarily + +/36 +. In control experiments, wh… more

Date: unknown

Creator: Friedman, L. R. & Sobell, H. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

''Aged'' (dense) circulating red cells contain normal concentrations of ATP

A newly-developed technique for determination of the ATP content of individual red cells to the densest, and hence presumably the oldest, cells from normal human blood was applied. It was found that these cells contain normal concentrations of ATP, although the net content of ATP is decreased. The essence of the technique is suspension of red cells in autologous plasma containing luciferin and luciferase, lysis of the cells with a pulse from a laser, and counting of the photoemissions resulting… more

Date: January 1, 1978

Creator: Kirkpatrick, F. H.; Muhs, A. G.; Kostuk, R. K. & Gabel, C. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Biochemical endpoints of glucocorticoid hormone action

Both the rapidly evolving metabolic effects of glucocorticoids and the more slowly developing lethal actions appear to be initiated via the synthesis of new mRNAs and proteins. The chronic suppression of cell growth may be the consequence of suppression of overall rates of protein synthesis (and probably RNA and DNA synthesis as well) that in turn may represent the cellular response to the small changes in ratios of adenine nucleotides that result from the suppression of oxidative ATP productio… more

Date: January 1, 1978

Creator: Young, D. A.; Nicholson, M. L.; Guyette, W. A.; Giddings, S. J.; Mendelsohn, S. L.; Nordeen, S. K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Does DNA have two structures in solution that coexist at equilibrium

The existence of two discrete structures for different regions of DNA at equilibrium in solution is postulated. These structures correspond to B DNA and to an inelastically deformed DNA structure, denoted ..beta.. kinked DNA. ..beta.. kinked DNA corresponds to a second order phase transition in the polymer, different regions of DNA undergoing this transition at different temperatures, and arises from a specific normal mode oscillation in DNA structure that is excited by Brownian motion of solve… more

Date: January 1, 1978

Creator: Lozansky, E. D.; Sobell, H. M. & Lessen, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sampling and analysis of suspended particles and vapors by continuum source particle beams

Two continuum source particle beam methods are proposed for the on-line measurement of suspended particles or material which is suspendable in a gas. The first method can be used to size separate the various molecular and particulate species present in the beam. The second method is used to obtain a molecular composition analysis of individual beam particles or a composition distribution for a sample containing a large number of particles. The two methods are complementary and can be used toget… more

Date: January 1, 1979

Creator: Dahneke, B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Visualization of drug-nucleic acid interactions at atomic resolution. IV. Structure of an aminoacridine/dinucleoside monophosphate crystalline complex, 9-aminoacridine: 5-iodocytidylyl(3'-5')guanosine

9-Aminoacridine forms a crystalline complex with the dinucleoside monophosphate, 5-iodocytidylyl(3'-5')guanosine (iodoCpG). These crystals are monoclinic, space group P2/sub 1/, with a = 13.98 A, b = 30.58 A, c = 22.47 A and ..beta.. = 113.9. The structure has been solved to atomic resolution by Patterson and Fourier methods, and refined by a combination of Fourier and sum function Fourier methods. The asymmetric unit contains four 9-aminoacridine molecules, four iodoCpG molecules and 21 water … more

Date: January 1, 1979

Creator: Sakore, T. D.; Reddy, B. S. & Sobell, H. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Decreased uv mutagenesis in cdc8, a DNA replication mutant of Saccharomyces cerevisiae

A DNA replication mutant of yeast, cdc8, was found to decrease uv-induced reversion of lys2-1, arg4-17, tryl and ural. This effect was observed with all three alleles of cdc8 tested. Survival curves obtained following uv irradiation in cdc8 rad double mutants show that cdc8 is epistatic to rad6, as well as to rad1; cdc8 rad51 double mutants seem to be more sensitive than the single mutants. Since uv-induced reversion in cdc8 rad1 and cdc8 rad51 double mutants is like that of the cdc8 single mut… more

Date: January 1, 1978

Creator: Prakash, L.; Hinkle, D. & Prakash, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low-energy ion-molecule reaction dynamics and chemiionization kinetics. Progress report, February 1, 1979-January 31, 1980. [H/sub 2//sup +/ + CO. -->. HCO/sup +/ + H]

Low energy studies of proton transfer and charge exchange reactions of H/sub 2//sup +/ were begun. A study of H/sub 2//sup +/ (CO, H) HCO/sup +/ was completed in the relative energy range 0.7 to 9.2 eV. Work has been initiated on the systems H/sub 2//sup +/ + He, Ne, Ar, N/sub 2/, and O/sub 2/. Construction on a tandem-mass spectrometer for the study of associative detachment reactions was begun.

Date: January 1, 1979

Creator: Farrar, J. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Visualization of drug-nucleic acid interactions at atomic resolution. VI. Structure of two drug/ dinucleoside monophosphate crystalline complexes, ellipticine: 5-iodocytidylyl(3'-5')guanosine and 3,5,6,8-tetramethyl-n-methyl phenanthrolinium: 5-iodocytidylyl(3'-5')guanosine

Ellipticine and 3,5,6,8-tetramethyl-N-methyl phenanthrolinium (TMP) form complexes with the dinucleoside monophosphate, 5-iodocytidylyl(3'-5')guanosine (iodoCpG). These crystals are isomorphous: ellipticine-iodoCpG crystals are monoclinic, space group P2/sub 1/, with a = 13.88 A, b = 19.11 A, c = 21.42 A, ..beta.. = 105.4; TMP-iodoCpG crystals are monoclinic, space group P2/sub 1/, with a = 13.99 A, b = 19.12 A, c = 21.31 A, ..beta.. = 104.9. Both structures have been solved to atomic resolutio… more

Date: January 1, 1979

Creator: Jain, S. C.; Bhandary, K. K. & Sobell, H. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Nuclear structure theory. Annual technical progress report, October 1, 1978-September 30, 1979. [Summaries of research activities at Univ. of Rochester]

This report summarizes progress during the past year in the following areas of nuclear structure and reaction theory: Statistical spectroscopy, including: Random matrix methods, with applications to fluctuations in spectra and in strength distributions, and to problems of ergodicity; Group symmetries in spectral-distribution theory; Electromagnetic and ..beta.. transitions. Meson scattering and absorption by nuclei, including: general scattering theory with absorption, multiple scattering theor… more

Date: January 1, 1979

Creator: French, J. B. & Koltun, D. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Materials and mechanics of rate effects in brittle fracture. Progress report, October 1978-October 1979

A thermodynamic formulation for a crack driving force has been experimentally used in linear elastic fracture mechanics, elastic plastic fracture mechanics and creep fracture. In linear elastic and elastic plastic fracture mechanics, mechanical stability criteria are established from the load versus the load point displacement in two test specimens that differ only in crack area. These tests have also been used to measure the fracture toughness in several heat treated steels. Creep cracking of … more

Date: October 1, 1979

Creator: Burns, S.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Behavioral assays in environmental toxicology

Environmental toxicology is too permeated by questions about how the whole organism functions to abandon intact animals as test systems. Behavior does not participate as a single entity or discipline. It ranges across the total spectrum of functional toxicity, from tenuous subjective complaints to subtle sensory and motor disturbances demanding advanced instrumentation for their evaluation. Three facets of behavioral toxicology that illustrate its breadth of interests and potential contribution… more

Date: January 1, 1979

Creator: Weiss, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Optical diffraction and spatial filtering of electron micrographs of biological materials

Optical diffraction and spatial filtering methods have been used to determine the characteristics of periodic structures in many biological materials. The head shell of bacteriophage T4 was chosen for this study, since aberrations in the assembly of the shell due to mutation or changes in growth conditions lead to the formation of a variety of elongated tubular head forms. The lattice parameters of structures assembled at elevated growth temperatures by normal, wild-type T4 and by a mutant (reg… more

Date: January 1, 1980

Creator: Wever, G. H.; Dunn, P.; Wiberg, J. S. & Thompson, B. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Diffusional creep of multicomponent systems. Progress report, February 1, 1980-January 31, 1981. [Dislocation-crack interactions; photoplastic and electroplastic effects in KCl]

Topics for which significant results are reported include dislocation-crack interactions, impression creep of Al polycrystals, and photoplastic and electroplastic effects in additively colored KCl. 9 figures. (DLC)

Date: January 1, 1981

Creator: Li, J.C.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

J/sub IC/ measured from unstable test specimens with finite differences in crack areas

The generalized force on a crack-like feature in an elastic solid has been shown to be J. J values have been determined from a series of test specimens that incrementally differ only in the crack area. Incremental differences in crack areas are used to approximate the derivative of the load on the specimen with respect to the crack area at constant loadpoint displacement. Such a testing scheme requires a large number of test specimens since an incremental limit is to be found. In the experiment… more

Date: October 1, 1978

Creator: Early, P.W. & Burns, S.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low energy ion-molecule reaction dynamics and chemiionization kinetics. Progress report, February 1, 1978--January 31, 1979. [Summaries of research activities at University of Rochester]

A crossed molecular beam apparatus for the study of low energy ion-molecule reactions and free-radical chemiionization kinetics was constructed, and its initial work was in the study of reactions of H/sub 2//sup +/ + CO, N/sub 2/, and Ar at energies between 5 and 10 eV. The preliminary results obtained indicate that in the energy range studied, the reactions proceed via impulsive, direct collisions. The molecular ion products are scattered in the backward direction with respect to the incoming … more

Date: January 1, 1979

Creator: J.M., Farrar

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Diffusional creep of multicomponent systems. Progress report, February 1, 1978--January 31, 1979

The achievements this year can be summarized as follows: (1) Successful completion of photoelastic studies of three dimensional stress field caused by a cylindrical punch. (2) Successful completion of pencil slip studies in ..beta..-Tin single crystals. (3) Equipment set up and preparation for experimental investigation of laser-excited diffusion and creep in solids. No positive results yet. Some negative results are described.

Date: January 1, 1979

Creator: Li, J.C.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of ferromagnetic spinels for optical isolation at 10. 6. mu. m. Progress report, November 1, 1976--January 31, 1977

During this quarter, measurements of the optical absorption coefficient, ..cap alpha.., of crystals of CdCr/sub 2/S/sub 4/ were measured at 10.6 ..mu..m and room temperature, and correlated with growth parameters established during the last quarter. A minimum absorption coefficient of 15.6 cm/sup -1/ was obtained. Procedures for hot forging crystals of CdCr/sub 2/S/sub 4/ were established in preparation for a study of the effect of forging on the optical absorption. Single crystals of CoCr/sub … more

Date: February 1, 1977

Creator: Teegarden, K. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of ferromagnetic spinels for optical isolation at 10. 6. mu. m. Progress report, August 1, 1976--October 31, 1976. [Summaries of research activities at University of Rochester]

During this quarter, emphasis was placed on the growth of small single crystals of CdCr/sub 2/S/sub 4/. The size and morphology of the crystals was studied as a function of growth parameters. Facilities for increasing the chemical purity of the crystals were constructed.

Date: November 1, 1976

Creator: Teegarden, K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Diffusional creep of multicomponent systems. Progress report, February 1, 1976--January 31, 1977. [Impression (indentation) creep]

Impression creep was established as a reliable substitute for conventional creep testing using bulk specimens. Impression creep tests on succinonitrile crystals established the stress and temperature dependences which agreed with literature values. Conventional compression creep confirmed the results. From the computer program of impression creep using finite element method, the calculated impressing velocities agreed with experimental values. Such agreement established the impression creep con… more

Date: January 1, 1976

Creator: Li, J. C. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low energy ion-molecule reaction dynamics and chemiionization kinetics. Progress report, February 1, 1980-January 31, 1981

Reactive scattering studies were completed over a wide energy range on the systems H/sub 2//sup +/ + Ar, H/sub 2//sup +/ + H/sub 2/O, H/sub 2//sup +/ + D/sub 2/O, and H/sub 2//sup +/ + Ne. Work was begun on the proton transfer system HCO/sup +/ + H/sub 2/O ..-->.. H/sub 3/O/sup +/ + CO.

Date: January 1, 1981

Creator: Farrar, J.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Environmental contaminants as origins of disordered behavior

Behavioral toxicology studies the behavioral effects of contaminants, such as heavy metals, in environmental and occupational settings. A classic example of metal poisoning with behavioral effects is Pink Disease, or acrodynia, due to mercurous chloride intoxication in children. Thalidomide is a more prominent example. Behavioral changes, unlike tangible consequences of pollution, are difficult to perceive as dangers and to correct. Other examples of environmental pollutants causing behavioral … more

Date: January 1, 1978

Creator: Weiss, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Materials and mechanics of rate effects in brittle fracture. Progress report, October 1979-October 1980

Energy balance methods have been used to find the crack driving force in elastic fractures. The fracture toughness of cracked steel bars have been measured using these techniques. Crack tip dislocations have been shown to protect the crack tip by having a stress intensity value that is opposite in sign from the applied stress intensity value. Thus, crack tip dislocation plasticity shields the crack from the external stress intensity factor. In the fatigue of LiF single crystals a relationship b… more

Date: January 1, 1980

Creator: Burns, S.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department