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The purpose of this study was to measure the effect of bone-patellar tendon-bone autograft harvest for anterior cruciate ligament (ACL) reconstruction on the surface strain of the human patella. Through progressive removal of bone from the patella, three different defect shapes as well as the intact patella were tested in each of seven knees. Maximum principal strain and corresponding principal direction were determined from each of three gages around the defect for the four conditions (intact plus three defect shapes). There were no statistically significant differences in overall average surface strain between any of the defect shapes. Following graft harvest, overall average strain (all three defects combined) increased in the patella both medial (15 percent increase) and lateral (34 percent increase) to the defect, while decreasing in the region directly proximal (22 percent decrease) to the harvest site compared to the intact patella. A statistically significant 7.5 deg shift of principal direction from longitudinal toward a more transverse (lateral-superior to medial-inferior) direction was observed in the medial region when a shallow-dome defect was made. We conclude that removal of a bone block from the anterior, inferior part of the patella induces a significant redistribution of the surface strain. This results in greater local strain adjacent to the upper border of the bone block, increasing the risk for patella fracture. This effect may be of importance in various complications known to occur after ACL reconstruction.

Season-long field studies were conducted in Washington apple orchards that compared the following: (1) twice per week releases of partially sterile codling moths, Cydia pomonella (L.), treated with either 100 or 250 Gy, and (2) combinations of mating disruption plus the release of partially sterile (100 Gy) codling moths, to control wild codling moth populations. No significant differences in the level of fruit damage at either midseason or harvest were found between any of thetreatments, or between the treatments and the inside controls. Damage in all plots was <0.1%. In both studies, trap data suggest that themovement of the 100 Gy-treated moths into the other treatments and the inside controls may have masked treatment effects. However, fruit damage was significantly lower in all treatment plots when compared with control plots located outside of the treatment areas. Results indicated that the release of partially sterile male (and fully sterile female) codling moths does not result in increased fruit injury and that the lower dose of radiation used to partially sterilize males results in insects that are more active, disperse greater distances and are generally more competitive. [ABSTRACT FROM AUTHOR]

We investigated the survival of Archytas marmoratus (Townsend) from superparasitized Helicoverpa zea (Boddie) larvae. About half of the plan idia ofA. marmoratus brushed on larvae of the corn earworm, H. zea, became established. Fourth instars were more susceptible to parasitization than other instars, but parasitoid eclosion from superparasitized hosts was greatest in fifth instars. The number of hosts producing A. marmoratus adults declined linearly with the number of maggotsper host, with no eclosion of A. marmoratus from hosts with >10 maggots. When third-instar corn earworm were collected from artificially infested, whorl-stage corn after the release of A. marmoratus, 75% ofthe parasitized larvae were superparasitized. Superparasitism reduced parasitoid eclosion more severely in field plots than in the laboratory. As in laboratory studies, the number of hosts producing A. marmoratus adults declined linearly with an increased number of maggots, but no parasitoid eclosed if hosts had more than four maggots. The number of maggots per corn earworm larva was highly correlated with percentage parasitism. Consequently, the release rate of A. marmoratus might need to he adjusted to host density so that superparasitism doesnot reduce the survival rate of the parasitoid. [ABSTRACT FROM AUTHOR]