A consistent feature of the Alpha-, Mu- and Pi-class glutathione transferases (GSTs) is the presence near the N-terminus of a tyrosine residue that contributes to the activation of glutathione. While this residue appears to be conserved in many Theta-class GSTs, its absence in some suggested that the Theta-class GSTs may have a significantly different structure or catalytic mechanism. The eluci...

Glycogen from flight muscle of the blowfly, Phormia regina, has been characterized ultrastructurally and biochemically. In situ, glycogen is in the form of rosettes, which vary in size with diameters of up to 0.1 micro. Sedimentation analysis of pure glycogen, isolated by mild buffer extraction, reveals a polydisperse molecular weight spectrum, with larger particles having molecular weights of ...

The sheep blowfly is an economically important ectoparasite of sheep, and impacts on animal health and welfare under pastoral conditions in South Africa. The absence of flystrike in the breech (ABS) was recorded in 2198 Merino hoggets on the Tygerhoek Research Farm. This trait was analysed together with dag score (DS; n=1623); neck wrinkle score (NWS; n=2162); midrib wrinkle score (MWS; n=2162)...

Many insects depend for survival on wide dispersal by flight. Small insects are carried about passively by air currents (Hardy & Milne, 1937, 1938; Freeman, 1945; Gisl6n, 1948; Johnson, 1954) and the displacement of even such a large and powerful form as a locust depends largely on the wind direction during flight (Waloff, 1946; Rainey & Waloff, 1948). Spontaneous flight activity is on the whol...

Bionomic features of blowflies may be clarified and detailed by the deployment of appropriate modelling techniques such as artificial neural networks, which are mathematical tools widely applied to the resolution of complex biological problems. The principal aim of this work was to use three well-known neural networks, namely Multi-Layer Perceptron (MLP), Radial Basis Function (RBF), and Adapti...

The first basalar muscle (b1) is one of 17 small muscles in flies that control changes in wing stroke kinematics during steering maneuvers. The b1 is unique, however, in that it fires a single phase-locked spike during each wingbeat cycle. The phaselocked firing of the b1's motor neuron (mnb1) is thought to result from wingbeat-synchronous mechanosensory input, such as that originating from the...

The role of 2 sets of interneurons in the optic lobes of blowflies in visual course control was studied by means of brain lesions. The first set comprises the cells HS and H2, which respond to global horizontal motion. The second set are the FD-cells, which respond selectively to local horizontal motion. All these cells are output neurons of the third optic ganglion of flies and are thought to ...

An analysis of the various parts of the electrical responses to the chemical and electrical stimulation of a single labellar chemosensory hair of the blowfly, Phormia regina, indicates that the recording conditions for the spike potentials approximate the intracellular recordings made in other types of sense cells. The large positive resting potential probably arises from the basement membrane ...