Life Sciences Commons^™

Metabolic Inhibition Of A Toluene-Enriched Microbial Population Due To Lead (Pb2+): Verification Of A Free Metal Ion Toxicity Model, Patrick J. S. Marbas

Theses and Dissertations

A dissolved oxygen probe and an ion specific electrode were used to study the lead-induced metabolic inhibition in a toluene-enriched microbial population. Predicted toxicity values were compared to the actual toxicity responses using a free metal ion toxicity model (TM) which linked metabolic inhibition with lead activity. Experimentally derived values for the model parameters (lead activity and a lead distribution coefficient) were used in the TM. It was postulated that cellular metabolism is disrupted by the conformational changes to the cell's plasma membrane produced by lead ion adsorption. The predicted toxicity values were higher than the actual toxicity response. This …

Copper Deficiency In Utah, Clell Bagley, Norris Stenquist, Dennis Worwood

All Current Publications

Copper deficiency has been diagnosed in a number of Utah cattle herds, yet few producers use copper supplements. Cattle deficient in the element can suffer significant production losses. Producers need to balance both the effects and the costs of copper supplements. Too much copper can cause copper toxicity or poisoning. And adding copper may not be economical if animals are only marginally deficient. Further, the deficiency may occur only on specific feeds or pastures, correcting itself when cattle are moved.

Clinical Trials With Copper Supplementation, Clell Bagley, Norris Stenquist, Dennis Worwood

All Current Publications

Copper deficiency has been diagnosed in beef cattle herds in many areas of the intermountain west. Copper supplements are not widely used, even though several products are available. It is difficult to correct a deficiency because too much copper can result in copper toxicity or poisoning. Toxicity is less a hazard with cattle than with sheep, but it is still a problem to guard against. Periodic monitoring of the herd’s copper status is essential for proper supplementation.

Effects Of Alachlor On An Algal Community From A Midwestern Agricultural Stream, Rebecca Spawn, Kyle D. Hoagland, Blair Siegfried

Department of Entomology: Faculty Publications

The effects of a single pulse, 21-d exposure of the commonly used herbicide alachlor (2-chloro-2′, 6′-diethyl-N-methoxymethyl acetanilide) on an algal community from a typical agricultural stream in Nebraska were studied using 18 stream microcosms located in a greenhouse, at six alachlor concentrations (0, 1, 10, 30, 100, and 1,000 μg/L). Effects of alachlor exposure at 1.0 μg/L were not significant (p < 0.05); however, at all other concentrations, alachlor had a significant negative effect on algal biomass. Differential taxonomic responses were observed, with approximately half the dominant algal taxa affected at levels >10 μg/L. Some taxa recovered from exposure by day 7, while others took longer or did not recover. A shift in the dominant algae was observed at higher concentrations (30, 100, 1,000 μg/L), and after 21 d these streams …

Ec97-782 Water Quality Criteria For Irrigation, Glenn J. Hoffman

University of Nebraska-Lincoln Extension: Historical Materials

In irrigated agriculture, the hazard of salt water is a constant threat. Poor-quality irrigation water is generally more concerning as the climate changes from humid to arid conditions. Salinity is not normally a threat where precipitation is a major source of salt-free water for crop production. Water entering the soil which is not stored or consumed by evapotranspiration moves through the crop root zone, eventually reaching the water table. This percolating process flushes (leaches) soluble salts. Less rainfall means smaller amounts of precipitation available to leach salts. In Nebraska, rainfall decreases from 30 inches in the east to 15 inches …

Ec97-2505 Signs And Symptoms Of Pesticide Poisoning, Larry D. Schulze, Clyde Ogg, Edward F. Vitzthum

University of Nebraska-Lincoln Extension: Historical Materials

Accidental exposure or overexposure to pesticides can have serious implications. The potential for pesticide accidents is real. It has been estimated that more than 36 million pounds of pesticide active ingredients are used annually in Nebraska. While most of these pesticides can be used with relatively little risk (as long as label directions are followed), some are extremely toxic and require special precautions.

The Poison Center, at the Children's Hospital in Omaha, reports that agricultural pesticides are responsible for 4.6 percent of all accidental exposures reported. A recent study surveyed callers to The Poison Center who were exposed to agricultural …

Clinical Trials With Copper Supplementation Of Cattle, Clell V. Bagley, Norris J. Stenquist, Dennis R. Worwood

All Archived Publications

No abstract provided.