Sedimentation pattern

The low- and high-speed baseline patterns and the 80 and 100 min. sedimentation patterns for each solution were read in the same manner. The data were transferred to a Radio Shack Model III computer for further treatment. 

First, the sample was examined by GPC, for which four columns of styragel of 106,10s, 104 and 103 A nominal pore size were used. The total number of theoretical plates as determined by acetone at a flow rate of 1 ml/min was ca. 26,000. The eluent was tetrahydrofuran. The chromatogram is shown in Figure 9, which indicates two peaks at ca. 21 and 24 counts. The former may be assigned to the tetra-chain, star-draped component, and the latter to the precursor. However, no complete separation of the two peaks was observed. For another comparison, velocity ultra-centrifugation was performed for the sample at 59,780 rpm using a 6-solvent for polystyrene, cyclohexane. The operation temperature was established at 35 °C, the 6-temperature, to minimize the concentration dependence of sedimentation velocity and other effects. A sedimentation pattern taken by UV-absorption is shown in Figure 10. It is seen that the separation of S-A sample into the two components was quite difficult even at a very low polymer concentration, 0.077 g/dl. 

DNA that contained both closed, circular DNA and supercoiled DNA. Would you expect to see two bands in the sedimentation pattern Explain. 

The enzyme from M. audouini cultured on wheat bran, initially called AMP deaminase (185), has been extensively purified (4000-fold) (188) and renamed ATP aminohydrolase because of greater activity on that substrate. The ultracentrifugal sedimentation pattern exhibited a large and small peak, but no evidence was presented regarding the identity of either. Requirements for catalytic cofactors were negative. 

Fig. 1. Sedimentation patterns of AMDH at various times of incubation at the indicated salt concentrations at 20°C. The appearance of an additional sedimentation boundary indicates dissociation of the native enzyme. From Pundak et al. (1981), with permission.

Alkaline sucrose centrifugation was introduced by McGrath and Williams,278 who showed that DNA from irradiated Escherichia coli sedimented more slowly than control DNA after lysis in alkali and that the sedimentation pattern approached that of the untreated DNA at increasing intervals after radiation treatment. Applying the procedure to mammalian cells, Lett and colleagues2 8 demonstrated rejoining of x-ray-induced strand breaks in the DNA of... 

M29. Myllyla, G., Aggregation of human blood platelets by immune complexes in the sedimentation pattern test. Scand. J. Haematol. Suppl. 19, 1-50 (1973). 

Spenceley, A.P. (1982) Sedimentation patterns in a mangal on Magnetic Island near Townsville, North Queensland, Australia. Singapore J. Trap. Geogr. 3, 100-107. 

Top. Sedimentation pattern (left to right) of frog liver car bamyl-P synthetase (35) containing 5.5 mg. of protein per ml. after incubation at 38°, for 5 minutes Bottom. Same preparation made 0.01M in acetyl glutamate, incubated at 38°for 5 minutes, and stored at 0 °for 48 hours... 

The distribution on the floodplain of particulate carbon derived from riverine inputs depends on its route of entry. In an investigation of sedimentation patterns during diffuse overbank flow onto the central Amazon floodplain, Mertes (1994) estimated that > 80% of the riverine particu-... 

Essentially similar conclusions have been reached by Grassmann et al. (1961) on the basis of an analysis of sedimentation patterns of denatured, acid-extracted calfskin collagen. They propose that the formation of the /3-component arises from cross-linking of two a components which may or may not be identical in amino acid composition, while a third component always present in small amount, the y component, represents a structure in which three a-components are cross-linked together. 

Haug G. H., Mashn M. A., Samthein M., Stax R., and Tiedemann R. (1995) Evolution of northwest Pacific sedimentation patterns since 6Ma site 882. Proc. ODP. Set Results 145, 293—315. 

Elder W. P. (1991) Molluscan paleoecology and sedimentation patterns of the Cenomanian-Turonian extinction interval in the southern Colorado Plateau region. In Stratigraphy,... 

Figure 4.10 (A) Cores extracted from the bed of the Boteti River at Samedupe Drift, Botswana, showing a range of geochemical sediments developed beneath the channel floor, including massive and pisolithic drainage-line silcretes (after Shaw and Nash, 1998). (B) Section of silcretes in the Mirackina palaeochannel, South Australia (after Ollier and Pain, 1996), showing the planform distribution of silcrete outcrops along the palaeochannel course and the relationship of silcrete to underlying non-silicified units. (C) Schematic representation of geochemical sedimentation patterns in the vicinity of a pan or playa (after Summerfield, 1982).

Rhee G-Y, Bush B, Bethoney CM, et al. 1993a. Reductive dechlorination of Aroclor 1242 in anaerobic sediments Pattern, rate, and concentration dependence. Environ Toxicol Chem 12(6) 1025-1032. 

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