We investigated the mechanisms conferring resistance to methyl-parathion (44-fold) and to methomyl (8-fold) in Tetranychus urticae from Greece by studying the effect of synergists on the resistance and the kinetic characteristics of various enzymes in a resistant strain (RLAB) and a susceptible reference strain (SAMB). It is shown that S,S,S-tributyl phosphorotrithioate, a synergist that inhibi...

Adult Vanessa indica and Argyreus hyperbius frequently forage on flower 21 nectar, but the former also utilize tree sap and rotting fruits. Compared to flower 22 nectar, these rotting foods are characterized by low sugar concentrations and the 23 presence of fermentation products (ethanol and acetic acid). We suspected that 24 gustatory responses by the receptors on the proboscis might differ i...

Interactions of peripheral inputs to the motoneuron of the kitten fetus as young as 3 weeks prenatal were studied by reflex discharge from the ventral root as well as by recording from single motoneurons. Facilitation was found between two synergists in fetuses 1 to 2 weeks before birth. Intracellular recording showed that the facilitation could be explained by summation of excitatory postsynap...

Quantitative telemetered electromyography from the four heads of the quadriceps femoris (vastus medialis, rectus femoris, vastus intermedius and vastus lateralis) during normal postures and locomotion (quadrupedal resting, walk/run, gallop and leaping) is presented for the brown lemur, Lemur fulvus. The vastus intermedius is the sole contributor to muscle recruitment during quadrupedal resting ...

Synergistic effects of verbutin, a member of aryl alkynyl derivatives, to three commonly used acaricides were evaluated with the modified Food and Agricultural Organization Larval Packet Test (FAO-LPT) against both susceptible and resistant strains of the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). These tick strains demonstrated various levels of r...

A CENTRIPETAL impulse volley traversing the myelinated afferent fibers in the nerve to a given muscle, or fraction thereof, is known to provoke a variety of reflex effects (4). By direct, or monosynaptic impingement upon motor nuclei it promotes the discharge of homonymous motoneurons, which is to say motoneurons supplying that given muscle or muscle fraction; it facilitates the response of mot...

Experience with the aflatoxin problem may provide a useful guide in dealing with problems that may arise with other mycotoxins. Characteristics of mycotoxin situations are delineated. A multidisciplinary approach is needed in the following problem cases: (i) Identification of the fungus responsible and isolation and characterization of the mycotoxin(s). (iO Accurate analytical methodology for d...

High levels of resistance to the major categories of insecticides, ie, organophosphorus, carbamates, pyrethroids, and DDT, have been detected in the diamondback moth in Taiwan. Synergist studies have provided insufficient evidence to show significant involvement of known metabolic systems, such as microsomal oxidation, esterase hydrolysis, and glutathione conjugation in organophosphorus and car...

The alkenyl acetates £9-12:Ac, zl l l -12:Ac and Zl l -14:Ac were identified as minor components of the C. murinana female pheromone blend by chemical analyses of volatile pheromone gland constituents and potential pheromone precursors, electrophysiological recordings from single receptor cells, and field trapping tests. Gland washes from virgin females contained these compounds at 3%, 10% and ...

It has been suggested that a suppression of maximal voluntary contraction (MVC) induced by prolonged vibration is due to an attenuation of Ia afferent activity. The purpose of the present study was to test the hypothesis that aftereffects following prolonged vibration on muscle activity during MVC differ among plantar flexor synergists owing to a supposed difference in muscle fiber composition....