Two metabolites of P. leptostromijormis (phomopsins A and B) have been isolated as a crystalline mixture from a culture of the fungus on lupin seed. The mixture has been shown to be capable of inducing lupinosis in sheep and in young rats. Key steps in the isolation were the transfer of the phomopsins from crude aqueous solution to tetrahydrofuran and chromatography on macroreticular polystyrene resin. The bioassays used in monitoring fractions were based on inhibition of cell cultures and the mitosis-arresting effect of the metabolites on liver cells in vivo.
The cost-effectiveness of identification and repair of vehicles with excessive carbon monoxide emissions was investigated over the 1991-92 winter period in Provo, Utah. This pilot program used on-road remote sensing at two locations to identify repeat gross polluting vehicles. The owners of gross polluters observed at one of the locations were solicited for a free repair program carried out under the direction of the Utah Valley Community College, Auto-Diesel Division. The same two locations were revisited after the repair program had terminated and the vehicle emissions were remeasured. More than 17,000 measurements of over 10,000 individual vehicles were obtained. As observed elsewhere, half of the total carbon monoxide was emitted by only about ten percent of the vehicles. Solicitation letters were sent to 114 owners and 47 vehicles were recruited and repairs attempted. Df the 47 vehicles, 28 were remeasured when the site was revisited at the end of the program. They had improved their measured on-road emissions by more than 50 percent. The vehicles which were identified as gross polluters at the second location-but were not notified of their status-were used as a control group. Their emissions were also reduced, as expected, but only by 14 percent. This pilot program demonstrates carbon monoxide emissions reduction at a cost effectiveness of $200 per ton, not including the cost benefits of gas mileage improvement. Two hundred dollars per ton is lowerthan many current or proposed mandated programs. The owner's repair cost would more than pay for itself in terms of improved fuel economy. The program would also generate the on-road fleet emissions data necessary to evaluate its effectiveness. Without such data, a program is forced to rely upon computer modeling with its known limitations. Most vehicles show CO/CO 2 and HC/ CO 2 ratios close to zero. When CO/CO 2 ratios greater than zero are observed, the engine must be operating with a fuel rich air/fuel ratio. In the case of a large HC/ CO 2 ratio, a fuel lean air/fuel ratio which is
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