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Publications

Read publications and other informational products to learn more about USGS science occurring in the Mississippi Basin.

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Some enzymatic properties of brain Acetylcholinesterase from bluegill and channel catfish Some enzymatic properties of brain Acetylcholinesterase from bluegill and channel catfish

Using a manometric technique an acetylcholinesterase (EC 3.1.1.7, acetylcholine acetyl-hydrolase) was demonstrated in brain tissue from the bluegill, Lepomis macrochirus Rafinesque, and the channel catfish, Ictalurus punctatus (Walbaum). The activities were 19 and 37 μmoles acetylcholine hydrolyzed/milligram protein per hour for the bluegill and channel catfish enzymes, respectively. The...
Authors
James W. Hogan, Charles O. Knowles

Electrophoretic separation of fish brain esterases Electrophoretic separation of fish brain esterases

Fish brains were homogenized in an all-glass Potter-Elvehjem-type tissue grinder in 40% sucrose solution. The homogenate concentration was 10 brains/ml for both the bluegill and channel catfish. The brei was centrifuged at 34,700 g for 30 min at 5 C, and 30 J.lliters of the supernatant were used per column for electrophoresis.
Authors
Charles O. Knowles, Suresh K. Arurkar, James W. Hogan

Some effects of mirex on two warm-water fishes Some effects of mirex on two warm-water fishes

The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex were incorporated into the diet and fed to fish held in plastic pools, and in the...
Authors
Charles C. Van Valin, Austin K. Andrews, Lafayette L. Eller

Availability of ground water in Decatur County, Iowa Availability of ground water in Decatur County, Iowa

Decatur County and several other counties in south-central Iowa comprise an area that has been chronically short of good-quality water. Municipalities, industries and rural water users alike have been affected by the water shortage. Municipalities have experienced serious problems in obtaining potable supplies adequate to keep pace with their growth and development: industrial expansion...
Authors
J.W. Cagle, W. L. Steinhilber

Dechlorination of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane by Aerobacter aerogenes: I. Metabolic products Dechlorination of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane by Aerobacter aerogenes: I. Metabolic products

Whole cells or cell-free extracts of Aerobacter aerogenes catalyze the degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) in vitro to at least seven metabolites: 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE); 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD); 1-chloro-2,2-bis(p-chlorophenyl)ethylene (DDMU); 1-chloro-2,2-bis(p-chlorophenyl)ethane (DDMS); unsym-bis(p...
Authors
Gary Wedemeyer

Contamination of the freshwater ecosystem by pesticides Contamination of the freshwater ecosystem by pesticides

A large part of our disquieting present-day pesticide problem is intimately tied to the freshwater ecosystem. Economic poisons are used in so many types of terrain to control so many kinds of organisms that almost all lakes and streams are likely to be contaminated. In addition to accidental contamination many pesticides are deliberately applied directly to fresh waters for suppression...
Authors
Oliver B. Cope

Dechlorination of DDT by Aerobacter aerogenes Dechlorination of DDT by Aerobacter aerogenes

Dechlorination of DDT to DDD in higher animals requires the presence of molecular oxygen, but in microorganisms the presence of oxygen hinders dechlorination. In cell-free preparations of Aerobacter aerogenes, the use of selected metabolic inhibitors indicated that reduced Fe(II) cytochrome oxidase was responsible for DDT dechlorination. This finding may possibly explain. the persistence...
Authors
Gary Wedemeyer

Some effects of Heptachlor on bluegills (Lepomis macrochirus) Some effects of Heptachlor on bluegills (Lepomis macrochirus)

In complementary studies of the chronic effects of heptachlor on bluegills, four similar earthen ponds were treated once with different concentrations of heptachlor, and the fish in six plastic pools were routinely fed different levels of heptachlor. A fifth pond and two plastic pools were used as controls. Higher dosages resulted in higher concentrations of heptachlor residues, more...
Authors
Austin K. Andrews, Bruce E. Stebbings, Charles C. Van Valin
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