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The necessary correction concerns Eq. ͑2͒ for the transverse magnetoelectric ͑ME͒ coefficient for a bilayer of magnetostrictive and piezoelectric phases. The exact expression given below takes into account the in-plane piezomagnetic coupling q 12 m measured perpendicular to the static magnetic field:The expression reduces to Eq. ͑2͒ for q 11 m ϭq 12 m . Such a condition, however, is not satisfied in nickel ferrite. Our estimation of q 12 m from data on magnetostriction for the ferrite indicates a small positive value for q 12 m ͑compared to a large negative value for q 11 m ͒. The corrected theoretical values of ␣ E,31 are thus a factor of 2 smaller than the estimates in Figs. 6 and 7. The overall good agreement between data and theory claimed in the work, however, is not affected by the correction to calculated values.

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The biology of the invasive Polistes dominulus and the native P. fuscatus was compared at a field site in Rochester, Michigan over a two-year period. Colonies nesting semi-naturally in plywood nestboxes were studied using videography, extensive surveys, and colony-specific marking of gynes.Both single-and multiple-foundress colonies of P. dominulus were significantly more productive than comparable colonies of P. fuscatus. The disparity in productivity was significantly more pronounced in single-foundress colonies than in multiple-foundress colonies. P. dominulus had significantly shorter larval and pupal development times than P. fuscatus, which allowed P. dominulus to produce its first workers about a week earlier than P. fuscatus. P. dominulus had a number of additional advantages over P. fuscatus that contributed to its productivity including (1) significantly less parasitism by Strepsiptera, (2) significantly greater probability of renesting after predation by raccoons, (3) significantly lower usurpation pressures, and (4) possibly longer foraging days . The recovery of colony-marked foundresses indicated that gynes of P. dominulus suffered significantly greater mortality than gynes of P. fuscatus during winter diapause and that foundresses of both species were equally, strongly philopatric.P. dominulus is likely replacing P. fuscatus in many areas of southeastern Michigan via indirect or exploitative competition. The two species may be competing for nest sites.

Solid-solid displacive, structural phase transformations typically undergo a discrete structural change from a parent to a product phase. Coupling electron microscopy, three-dimensional atom probe, and first-principles computations, we present the first direct evidence of a novel mechanism for a coupled diffusional-displacive transformation in titanium-molybdenum alloys wherein the displacive component in the product phase changes continuously with changing composition. These results have implications for other transformations and cannot be explained by conventional theories.