Most hummingbirds and some species of nectar bats hover while feeding on floral nectar. While doing so, they achieve some of the highest mass-specific V(O(2)) values among vertebrates. This is made possible by enhanced functional capacities of various elements of the 'O(2) transport cascade', the pathway of O(2) from the external environment to muscle mitochondria. Fasted hummingbirds and necta...

Wilson's storm petrel (Oceanites oceanicus) characteristically feeds by ' hovering' over the water surface, but its technique for this is unlike that of other flying vertebrates. The kinematics and aerodynamics of this ' hovering' flight were investigated to determine the possible sources of lift; various nonaerodynamic sources of lift were discounted. It is suggested that the storm petrel soar...

Birds usually moult their feathers in a particular sequence which may incur aerodynamic, physiological and behavioural implications. Among birds, hummingbirds are unique species in their sustained hovering flight. Because hummingbirds frequently hover-feed, they must maintain sufficiently high flight capacities even when moulting their flight feathers. A hummingbird wing consists of 10 primary ...

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....

a 32-year-old man was attacked by flies while camping around khorram abad, lorestan province, western iran. pruritic dermatitis with marked edema and considerable discomfort appeared mainly on the lower legs. the flies were identified as simulium . simuliids are tiny bloodsucking flies, popularly known as blackflies or buffalo flies, belonging to the dipterous, family simulidae. they are occurr...

Olive fly is the most dangerous pest in olive groves worldwide. Therefore the study of the most susceptible and resistant cultivars to olive fly can bring new information to diminish the olive flies harmful impacts. The main goal of the present study is to verify the olfactory response of olive fly to olive volatiles from five native Iranian cultivars (Fishomi, Mari, Rowghani, Shengeh, and Zard...

Control and trajectory generation algorithms for a quadrotor helicopter with variable-pitch propellers are presented. The control law is not based on near-hover assumptions, allowing for large attitude deviations from hover. The trajectory generation algorithm fits a time-parametrized polynomial through any number of waypoints in R, with a closed-form solution if the corresponding waypoint arri...

Unmanned aerial vehicles (UAVs) have recently gained growing popularity in wireless communications owing to their many advantages such as swift and cost-effective deployment, line-of-sight (LoS) aerial-to-ground link, and controllable mobility in three-dimensional (3D) space. Although prior works have exploited the UAV’s mobility to enhance the wireless communication performance under different...

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Population cycles have fascinated ecologists since the early nineteenth century, and the dynamics of insect populations have been central to understanding the intrinsic and extrinsic biological processes responsible for these cycles. We analyzed an extraordinary long-term data set (every 5 days for 48 years) of a tea tortrix moth (Adoxophyes honmai) that exhibits two dominant cycles: an annual ...