Wing pitch reversal, the rapid change of angle of attack near stroke transition, represents a difference between hovering with flapping wings and with a continuously rotating blade (e.g. helicopter flight). Although insects have the musculature to control the wing pitch during flight, we show here that aerodynamic and wing inertia forces are sufficient to pitch the wing without the aid of the m...

Wing patterns are key taxonomic characters that have long been used in descriptions of Lepidoptera; however, wing pattern homologies are not understood among different moth lineages. Here, we examine the relationship between wing venation and wing pattern in the genus Micropterix, among the most basal extant Lepidoptera, in order to evaluate the two existing predictive models that have the pote...

The process of wing patterning involves precise molecular mechanisms to establish an organizing center at the dorsal-ventral boundary, which functions to direct the development of the Drosophila wing. We report that misexpression of dLMO, a Drosophila LIM-only protein, in specific patterns in the developing wing imaginal disc, disrupts the dorsal-ventral (D-V) boundary and causes errors in wing...

Recent investigations on the aerodynamics of natural fliers have illuminated the significance of the leading-edge vortex (LEV) for lift generation in a variety of flight conditions. A well-documented example of an LEV is that generated by aircraft with highly swept, delta-shaped wings. While the wing aerodynamics of a manoeuvring aircraft, a bird gliding and a bird in flapping flight vary signi...

In order to study the role of the passive deformation in the aerodynamics of insect wings, we computationally model the three-dimensional fluid–structure interaction of an elastic rectangular wing at a low aspect ratio during hovering flight. The code couples a viscous incompressible flow solver based on the immersedboundary method and a nonlinear finite-element solver for thin-walled structure...

The development of flapping-wing micro air vehicles (MAVs) demands a systematic exploration of the available design space to identify ways in which the unsteady mechanisms governing flapping-wing flight can best be utilized for producing optimal thrust or maneuverability. Mimicking the wing kinematics of biological flight requires examining the potential effects of wing morphology on flight per...

Case Description-An adult golden eagle with a wound on its right wing caused by gunshot was presented to the University of Tabriz, Veterinary Teaching Hospital. Clinical Finding-Clinical examination and radiographs, revealed compound fracture in distal third of humerus, severe soft tissue compromise and irreparable loss of blood supply. Anemia and leukocy...

We investigated the genetic background of intraspecific variation in wing color across an elevational gradient in the butterfly Colias philodice eriphyle. The degree of wing melanization was an accelerating function of elevation, and differences in wing melanization persisted in a common environment. Full-sibling analysis and parent-offspring regression yielded consistent, moderate to high heri...

At CONTEXT’99, the author described the ATT-Meta context-based system for (a) reasoning uncertainly about agents’ beliefs and (b) performing some of the uncertain reasoning needed for the understanding of metaphorical language. ATT-Meta’s handling of uncertainty is qualitative, and includes provisions for adjudicating conflicts between different lines of reasoning. But most of the detail on con...