Ralph A. Olsen

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The tricyclic quinolone antibacterial agent 6,7-dihydro-5,8-dimethyl-9-fluoro-1-oxo-1H,5H-benzo[ij]quinolizine -2-carboxylic acid has an asymmetric center at position 5 of the molecule. The R and S isomers of the compound have been prepared from the corresponding (R)- and (S)-2,5-dimethyl-6-fluoro-1,2,3,4-tetrahydroquinolines, which were separated via their(More)
Annotated genomes can provide new perspectives on the biology of species. We present the first de novo whole genome sequencing for the pink-footed goose. In order to obtain a high-quality de novo assembly the strategy used was to combine one short insert paired-end library with two mate-pair libraries. The pink-footed goose genome was assembled de novo(More)
An understanding of the chemistry and reactions of humic acids and related substances is crucial to an understanding of the nature and properties of soils. A comprehensible structural representation of humic substances is presented and the simplified model is used to illustrate: (i) the way in which stable humus is formed from lignin; (ii) forms of organic(More)
The relationship between Fe nutritional status and Verticillium wilt disease in tomatoes possessing single gene resistance to Race 1 of Verticillium dahliae was investigated using hydroponic culture media. Iron limiting conditions increased the sensitivity of resistant tomatoes to the pathogen as expressed by wilting and chlorosis. Distance of fungal(More)
The release of Fe from horse spleen ferritin through photochemical reduction of Fe3+ to Fe2+ was studied in vitro. Spectrophotometric measurement of the Fe(Ferrozine)3 4− complex (specific for Fe2+) was used to quantify rates of Fe2+ mobilization. Light radiation from cool white fluorescent plus incandescent bulbs effectively promoted the rate of Fe2+(More)
The general acceptance of diffusion as a rate-limiting step in transferring ions to plant roots was considered in characterizing soil fertility. Soil ion diffusive flux measurements to an exchange resin were measured with two soil: resin cells, one with untreated soil, the other with the same soil fertilized with P, K, and Cl. The P, K, and Cl that diffused(More)
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