Resistance is costly: trade-offs between immunity, fecundity and survival in the pea aphid.

Parasitoids are among the most important natural enemies of insects in many environments. Acyrthosiphon pisum, the pea aphid, is a common pest of the leguminous crops in temperate regions. Pea aphids are frequently attacked by a range of endoparasitic wasps, including the common aphidiine, Aphidius ervi.

Flooding of Ganymede's bright terrains by low-viscosity water-ice lavas.

Large regions of the jovian moon Ganymede have been resurfaced, but the means has been unclear. Suggestions have ranged from volcanic eruptions of liquid water or solid ice to tectonic deformation, but definitive high-resolution morphological evidence has been lacking. Here we report digital elevation models of parts of the surface of Ganymede, derived from stereo pairs combining data from the Voyager and Galileo spacecraft, which reveal bright, smooth terrains that lie at roughly constant elevations 100 to 1,000 metres below the surrounding rougher terrains.

Outcome of corneal and laser astigmatic axis alignment in photoastigmatic refractive keratectomy.

Purpose: To compare the refractive results of laser astigmatic treatment in eyes in which the astigmatic axes of the eye and laser are aligned by limbal marking at the 6 o'clock position and in eyes that are not marked.

Setting: University Hospital and Clinics, Madison, Wisconsin, USA.

Methods: This retrospective study comprised 143 eyes that had photoastigmatic refractive keratectomy with the VISX Star excimer laser.

Filtration surgery in rabbits treated with diclofenac or prednisolone acetate.

We performed filtration surgery in one eye of each of 28 rabbits. Either a nonsteroid (diclofenac) or a steroid (prednisolone acetate) was given as a postoperative antiinflammatory agent. On no examination day was there a significant difference in the intraocular pressure of the rabbits that had received diclofenac as contrasted with those that had received prednisolone acetate (P > .

Analysis of diode, argon, and Nd: YAG peripheral iridectomy in cadaver eyes.

We compared semiconductor diode, neodymium (Nd): YAG and argon laser iridectomies performed in 14 cadaver eyes using Miyake videographic, histologic and scanning electron analysis. We found that the diode laser created an iridectomy in < 10 applications in blue, hazel and brown irides using 1000-1200 mW over 0.5 seconds.