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Research in Photosynthesis

Description: The determination of the specific radioactivities of the chlorophylls and carotenoids of algae after photosynthesis with C/sup 14/O/sub 2/ is a formidable task, due to the extreme lability of these compounds. The whole success of the method depends on adequate chromatographic separations of the pigments from the colorless contaminants which are closely associated with them, and yet the time involved for such separations is sufficient for marked decomposition of the pigments to occur. It is sugg… more
Date: September 1, 1959
Creator: Anderson, Joan Mary
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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A molecular genetic analysis of carotenoid biosynthesis and the effects of carotenoid mutations on other photosynthetic genes in Rhodobacter capsulatus

Description: The nine known R. capsulatus carotenoid genes are contained within the 46 kilobase (kb) photosynthesis gene cluster. An 11 kb subcluster containing eight of these genes has been cloned and its nucleotide sequence determined. A new gene, crtK, has been located in the middle of the subcluster. The carotenoid gene cluster contains sequences homologous to Escherichia coli ..omega../sup 70/ promoters, rho-independent transcription terminators, and prokaryotic transcriptional factor binding sites. Th… more
Date: April 1, 1989
Creator: Armstrong, Gregory Aleksandr
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continental Shelf Processes Affecting the Oceanography of the South Atlantic Bight. Progress Report, 1 June 1979-31 May 1980

Description: The papers included in this progress report summarize some significant developments in understanding the South Atlantic Bight. Some of the results are summarized as follows: Onslow Bay flushing rates can be determined using a model based on an exponential dilution model; eddy induced nitrate flux accounts for most input of new nitrogen into shelf waters; and tarballs in the Gulf Stream are not transported to the nearshore because of an apparent inner shelf density front.
Date: February 29, 1980
Creator: Atkinson, L. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continental Shelf Processes Affecting the Oceanography of the South Atlantic Bight. Progress Report, June 1, 1979-May 31, 1980

Description: Progress is reported on research conducted from June, 1979 to May, 1980 on various oceanographic aspects of the South Atlantic Bight. Research topics included: (1) A flashing model of Onslow Bay, North Carolina based on intrusion volumes; (2) A description of a bottom intrusion in Onslow Bay, North Carolina; (3) Detailed observations of a Gulf Stream spin-off eddy on the Georgia continental shelf; (4) Pelagic tar of Georgia and Florida; (5) A surface diaton bloom in response to eddy-forced upwe… more
Date: February 29, 1980
Creator: Atkinson, L. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continental Shelf Processes Effecting the Oceanography of the South Atlantic Bight. Hydrography of Onslow Bay, North Carolina: September 1975 (OBIS II). Progress Report

Description: Over the course of OBIS II, 3-14 September, two intrusion cores were observed. One was apparently trapped nearshore over much of the study period, but as time went on, it either dissipated, moved too far shoreward or moved too far laterally along the shelf to be detected by the existing observational grid. The other (later) intrusion was first detected on 5-7 September and was observed to be moving into the Bay from the southeast over the remainder of the study period. Plots of the horizontal t… more
Date: March 12, 1976
Creator: Atkinson, L. P.; Singer, J. J.; Dunstan, W. M. & Pietrafesa, L. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrography of Onslow Bay, North Carolina: September 1975 (OBIS II)

Description: Data collected during studies of Onslow Bay, off the North Carolina coast during cruises during September, 1975, are reported. Current meters and thermography were placed at depths of 10 and 22 m along the 28 m isobath in the northeastern and southwestern sectors of the Bay. Data are included on wind turbulence and velocity; seawater salinity and temperature at various depths; the content of nitrates, phosphates, silicate, oxygen, chlorophyll, and phytoplankton biomass at various depths. Hydrog… more
Date: September 1, 1975
Creator: Atkinson, L. P.; Singer, J. J.; Dunstan, W. M. & Pietrafesa, L. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Performance of a Motor, a Switch, and Two Types of Pressure Pickup in a High-Gamma-Flux Environment

Description: To determine the effects of gamma radiation upon transducers, switches, and motors, two test assemblies were irradiated in the ANL Gamma Irradiation Facility at levels of 1.50 x 10/sup 5/to 2.10 x 10/sup 6/ rad/hr to a total dose of 1.0 x 10/sup 9/ rad. The components tested were a motor, a straingage pressure pickup, a quartz pressure pickup, and a high-temperature switch. The performances of the straingage pickup and snap switch were highly satisfactory over the test period. The quartz pickup… more
Date: June 1, 1961
Creator: Ayer, J. E. & Pokorny, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shelf Edge Exchange Processes: 2, SEEP2-09, R/V ENDEAVOR cruise 193: Hydrographic data report

Description: The R/V ENDEAVOR cruise 193, SEEP2-09, took place from 17--23 March 1989 and focused primarily on biological processes in the SEEP2 area. Mooring 1 was recovered and re-deployed and a replacement for mooring 4 was deployed. A 24 hour time series was conducted at mooring 1 to study primary and secondary production. The time series involved sampling nutrients, dissolved oxygen, chlorophyll {und a}, zooplankton abundance and distribution and fecal pellet production. Experiments to estimate grazing… more
Date: January 1, 1990
Creator: Behrens, W. J.; Wilson, C.; Flagg, C. N.; Wallace, D. W. R.; Wilke, R. J. & Wyman, K. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inborn anemias in mice. Progress report, 1 May 1977--31 July 1978

Description: Hereditary anemias of mice have been the chief objects of investigation. At present under study are four macrocytic anemias, four hemolytic anemias, nonhemolytic microcytic anemia, transitory siderocytic anemia, sex-linked iron-transport anemia, and the autoimmune hemolytic anemia of NZB. Each of these blood dyscrasias is caused by the action of a unique mutant gene, which determines the structure of different intracellular molecules, and thus controls a different metabolic process. Thus our wi… more
Date: August 1, 1978
Creator: Bernstein, S. E. & Russell, E. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Enzymes of respiratory iron oxidation

Description: This report describes experimental progress in characterizing and identifying redox proteins in a number of iron-oxidizing bacteria. Sections of the paper are entitled (1) In Situ electrolysis was explored to achieve enhanced yields of iron-oxidizing bacteria, (2)Structure/function studies were performed on redox-active biomolecules from Thiobacillus ferrooxidans, (3) Novel redox-active biomolecules were demonstrated in other iron autotrophs, and (4) New probes of metalloprotein electron-transf… more
Date: January 1, 1992
Creator: Blake, R., II
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PS2004 Light-harvesting Systems Workshop

Description: This special issue of the international scientific research journal Photosynthesis Research consists of 25 original peer-reviewed contributions from participants in the PS 2004 Lisht-Harvesting Systems Workshop. This workshop was held from 26-29, 2004 at Hotel Le Chantecler, Sainte-Adele, Quebec, Canada. The workshop was a satellite meeting of the XIII International Congress on Photosynthesis held August 29-September 3, 2004 in Montreal, Canada. The workshope dealt with all types of photosynthe… more
Date: November 1, 2005
Creator: Blankenship, Robert E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure, Function and Reconstitution of Antenna Complexes from Green Photosynthetic Bacteria

Description: This project is concerned with the structure and function of the chlorosome antennas found in green photosynthetic bacteria. Chlorosomes are ellipsoidal structures attached to the cytoplasmic side of the inner cell membrane. These antenna complexes provide a very large absorption cross section for light capture. Evidence is overwhelming that the chlorosome represents a very different type of antenna from that found in any other photosynthetic system yet studied. It is now clear that chlorosomes… more
Date: August 10, 2005
Creator: Blankenship, Robert E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structure, Function and Reconstitution of Antenna Complexes of Green Photosynthetic Bacteria

Description: Most chlorophyll-type pigments in a photosynthetic organism function as an antenna, absorbing light and transferring excitations to a photochemical reaction center where energy storage takes place by a series of chemical reactions. The green photosynthetic bacteria are characterized by large antenna complexes known as chlorosomes, in which pigment-pigment interactions are of dominant importance. The overall objective of this project is to determine the mechanisms of excitation transfer and regu… more
Date: June 10, 2005
Creator: Blankenship, Robert E.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Synoptic surveys of major reservoirs in South Carolina, 1988--1989

Description: Comprehensive synoptic surveys of ten South Carolina airs (L Lake, Savannah River Site (SRS), Par Pond, SRS, Pond B, SRS, Lake Moultrie, Lake Marion, Lake Murray, Lake Monticello, Lake Robinson, Lake Richard B. Russell, and Lake Greenwood) were performed to characterize and compare these basins with regard to water quality, trophic status, and community structure during September 1988 and September 1989. All of the reservoirs were mesoeutrophic to eutrophic having significantly greater producti… more
Date: March 1, 1992
Creator: Bowers, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical Simulations and Ultrafast Pump-probe Spectroscopy Experiments in Pigment-protein Photosynthetic Complexes

Description: Theoretical simulations and ultrafast pump-probe laser spectroscopy experiments were used to study photosynthetic pigment-protein complexes and antennae found in green sulfur bacteria such as Prosthecochloris aestuarii, Chloroflexus aurantiacus, and Chlorobium tepidum. The work focused on understanding structure-function relationships in energy transfer processes in these complexes through experiments and trying to model that data as we tested our theoretical assumptions with calculations. Theo… more
Date: September 12, 2000
Creator: Buck, D. R.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Molecular genetic and molecular evolutionary studies on the bacteriochlorophyll synthesis genes of Rhodobacter capsulatus

Description: Rhodobacter capsulatus, purple bacterium capable of either aerobic or photosynthetic growth, has proven to be very useful in genetic studies of photosynthesis. Forty-four genes clustered together within a 46 kilobase region are required to establish photosynthetic ability in R. capsulatus. Approximately twenty of these genes are involved in bacteriochlorophyll synthesis of which eight bch'' genes are the subject of this thesis. Six of these genes were found to code for the two ring reductases. … more
Date: August 1, 1992
Creator: Burke-Agueero, D. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CHEMICAL EVOLUTION

Description: How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in whi… more
Date: June 1, 1965
Creator: Calvin, Melvin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Differential gene expression in C4 plants. Research proposal, February 1, 1982-January 31, 1983. [Pea plants]

Description: The topic of this research proposal is slightly different from that originally outlined. Specifically, instead of characterizing the genes encoding the small subunit of RuBP carboxylase and the chlorophyll a/b binding polypeptide from corn, these genes from pea are being characterized. The above polypeptides represent the major products of cytoplasmic protein synthesis in green leaves. CDNA clones encoding the above polypeptides were isolated and characterized. Both of these cDNA clones have no… more
Date: November 1, 1981
Creator: Cashmore, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Protein response to ligation reactions in myoglobin

Description: The protein response to the photodissociation, escape and subsequent rebinding of carbon monoxide in myoglobin is studied using time-resolved infrared (TRIR) spectroscopy. All phases of these reactions areinvestigated, from ultrafast phenomena (picoseconds) to relatively slow processes (milliseconds). Conformational changes in myoglobin (Mb) are detected by time-resolved absorption changes in the amide I band. On the hundreds of nanoseconds to milliseconds timescale, a real-time'' apparatus is … more
Date: January 1, 1992
Creator: Causgrove, T.P. & Dyer, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Discovery of Unusual Minerals in Paleolithic Black Pigments from Lascaux (France) and Ekain (Spain)

Description: Analyses of archaeological materials aim to rediscover the know-how of Prehistoric people by determining the nature of the painting matter, its preparation mode, and the geographic origin of its raw materials. This study deals with identification of manganese oxides in black pigments by micro-XANES (X-ray absorption near-edge structure) based on previous TEM (transmission electron microscopy) studies. Complex mixtures of the manganese oxides studied are present in some of mankind's oldest known… more
Date: December 13, 2006
Creator: Chalmin, E.; Farges, F.; Vignaud, C.; Susini, J.; Menu, M. & Brown, G. E., Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Environmental effects on electron transfer from chlorophyll triplet to quinone: role of dielectric constant, viscosity and quinone structure in cellulose acetate films

Description: The effects of environmental parameters on chlorophyll triplet quenching and electron transfer to quinones have been investigated in a system consisting of donor and acceptor incorporated into a cellulose acetate film which was subsequently exposed to solvent. Triplet quenching by a diffusional mechanism was found to occur in the dry film, with steric effects being a major determinant of quencher effectiveness. No formation of separated radicals was found under these conditions, probably becaus… more
Date: January 1, 1981
Creator: Cheddar, G. & Tollin, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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