Knives, birds' wings, and mountain slopes are used for certain purposes: cutting, flying, and climbing. A bird's wings have in common with knives that they have been 'designed' for the purpose they serve, which purpose accounts for their existence, whereas mountain slopes have come about by geological processes independently of their uses for climbing. A bird's wings differ from a knife in that...

Front wings are a key element in the aerodynamic performance of Formula 1 race cars. Thus, their optimisation makes an important contribution to cars races. However, design is constrained by regulation, which it more difficult find good designs. The present work develops hybrid shape approach obtain optimal five-element airfoil front wing under FIA regulations and 17 parameters. A first baselin...

Scientists long thought they knew what the wings of early birds looked like. But new reconstructions of Archaeopteryx and its kin suggest quite different feather arrangements on their wings with profound implications for the evolution of flight.

Hummingbirds are the only birds that can sustain hovering. This unique flight behaviour comes, however, at high energetic cost. Based on helicopter and aeroplane design theory, we expect that hummingbird wing aspect ratio (AR), which ranges from about 3.0 to 4.5, determines aerodynamic efficacy. Previous quasi-steady experiments with a wing spinner set-up provide no support for this prediction....

For a century, researchers have used the standard lift coefficient C(L) to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv(2), where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex ad...

Natural and anthropogenic static electric fields are commonly found in the environment and can have both beneficial and harmful effects on many animals. Here, we asked how the fruitfly responds to these fields and what the consequences of exposure are on the levels of biogenic amines in the brain. When given a choice in a Y-tube bioassay Drosophila avoided electric fields, and the greater the f...

A high quality Keck spectrum of the Hα line in NGC 4395 reveals symmetric exponential wings, fv ∝ e, with σ ≃ 500 km s. The wings extend out to > ∼ 2500 km s from the line core, and down to a flux density of < ∼ 10 of the peak flux density. Numerical and analytic calculations indicate that exponential wings are expected for optically thin, isotropic, thermal electron scattering. Such scattering...

By Aditi Kannan, M.S. Washington State University May 2009 Chair: Karen Killinger Poultry is a known source of foodborne pathogens; therefore, processing interventions to reduce pathogens are critical. Washington mobile poultry slaughter operators wanted to identify an antimicrobial rinse alternative to chlorine to assist with product organic labeling and increase consumer appeal. Lab and field...

Experiments have been carried out at sub-critical Reynolds number to investigate free-to-roll motions induced by forebody and/or wings complex flow on a 30° swept back nonslender wings-slender body-model for static and dynamic (pitch-up) cases. For the dynamic (pitch-up) case it has been observed that roll amplitude decreases and lag increases with increase in pitching speed. Decrease in roll a...

Highly sensitive simultaneous observations of the 2→1 line of the first vibrationally excited state of SiO, and of the 2→1 line of CO have been obtained toward 37 O-rich evolved stars. In ∼ 45% of these objects, the SiO line profiles present unusually broad wings, reaching, and in some cases exceeding, the terminal velocity of the circumstellar envelope. All of the objects exhibiting SiO line w...