Widespread planting of crops genetically engineered to produce insecticidal toxins from the bacterium Bacillus thuringiensis (Bt) imposes selection on many key agricultural pests to evolve resistance to Bt. Fitness costs can slow the evolution of Bt resistance. We examined effects of entomopathogenic nematodes on Þtness costs of Bt resistance in the pink bollworm, Pectinophora gossypiella (Saun...

S U M M A R Y Quantitative correlations between the magnetic fabric (magnetic susceptibility or remanent magnetic anisotropies), single mineral anisotropy , and preferred mineral orientation is investigated using computer modelling. The influences of various initial fabric patterns and imposed strain on the magnetic fabric are simulated using multiparticle systems represented by their magnetic ...

Off-road cars’ windshields are vulnerable to different types of stones, road debris and pebbles due to common off paved and gravel surfaces in which they drive. Any attempt to design windshield that minimizes injury and death of occupants during a vehicle accident requires a thorough understanding of the mechanical behavior of automotive windshield subjected to foreign object impact loads...

BACKGROUND Although vaccination can be a useful tool for control of avian influenza epidemics, it might engender emergence of a vaccine-resistant strain. Field and experimental studies show that some avian influenza strains acquire resistance ability against vaccination. We investigated, in the context of the emergence of a vaccine-resistant strain, whether a vaccination program can prevent the...

The first silicon-carbon hybrid ladderanes consisting of trisila and tricarba ladder rails were obtained by the reactions lithium disilenide R2Si=SiRLi (R=2,4,6-triisopropylphenyl) with allylchlorosilanes. steric strain in 1,2,6-trisilabicyclo[2.2.0]hexanes imposed bulky substituents leads to highly distorted ring systems extreme puckering long bridgehead bonds. All show strong absorptions UV/v...

Biological molecules can form hydrogen bonds between nearby residues, leading to helical secondary structures. The associated reduction of configurational entropy leads to a temperature dependence of this effect: the helix-coil transition. Since the formation of helices implies a dramatic shortening of the polymer dimensions, an externally imposed end-to-end distance R affects the equilibrium h...