The Hertz Corporation

About: The Hertz Corporation is a based out in . It is known for research contribution in the topics: Population & Soil water. The organization has 9562 authors who have published 11044 publications receiving 447929 citations. The organization is also known as: Hertz Rental Car & Hertz Rent-a-Car.

Response of the seven-spot ladybird to an aphid alarm pheromone and an alarm pheromone inhibitor is mediated by paired olfactory cells.

Abstract: Electrophysiological responses of adult seven-spot ladybirds, Coccinella septempunctata, to (E)-β-farnesene, an aphid alarm pheromone, and (−)-β-caryophyllene, a plant-derived alarm pheromone inhibitor, were investigated by recording from single olfactory cells (neurons) on the antenna. Cells having high specificity for each of the two compounds were identified. Furthermore, these two cell types were frequently found in close proximity, with a larger amplitude consistently recorded for the cell responding specifically to (E)-β-farnesene. Preliminary behavioral studies in a two-way olfactometer showed that walking adults were significantly attracted to (E)-β-farnesene; this activity was inhibited with increasing proportions of (−)-β-caryophyllene. The possible ecological significance of colocation or pairing of olfactory cells for semiochemicals with different behavioral roles is discussed.

Biochemical aspects of biosensors

Abstract: A review of the major types of biological molecules and systems (including antibodies, enzymes and whole cells) on which biosensors can be based is presented. Specific emphasis is placed on a critical assessment of the relative strengths and weaknesses of the respective technologies and on analysis of the importance of practical considerations such as sample interference, signal-to-noise ratio and biomolecule stability. The importance of efficient coupling of the biological and transducer components of a biosensor is highlighted. Future trends and directions in biosensor research and commercial aspects of the technology are also discussed. The article concludes with a summary of current biosensor research activities at the GEC-Marconi Hirst Research Centre.

A comparison of 5-hydroxytryptamine receptors mediating contraction in rabbit aorta and dog saphenous vein: evidence for different receptor types obtained by use of selective agonists and antagonists

Abstract: Using recently available selective agonists and antagonists we have examined further our postulate (Apperley et al., 1980) that 5-hydroxytryptamine (5-HT) mediates contraction of dog saphenous vein via a different 5-HT receptor type from that in the rabbit aorta. In the rabbit isolated aorta, ketanserin and spiperone were potent, specific, competitively-acting antagonists of the contractile effects of 5-HT. In contrast, in the dog isolated saphenous vein neither ketanserin nor spiperone caused any rightward displacement of concentration-response curves to 5-HT although the maximum response was reduced by about 10%. In the rabbit aorta 5-carboxamidotryptamine (5-CONH2-T) was a weak agonist whilst the 5-N,N-dimethyl and 5-N-ethyl derivatives were even weaker or inactive. The contractile effect of 5-CONH2-T in the rabbit aorta was potently and competitively antagonized by ketanserin. In contrast, in the dog saphenous vein 5-CONH2-T and its 5-N,N-dimethyl and 5-N-ethyl derivatives were all potent agonists. The contractile effect of 5-CONH2-T was not markedly affected by ketanserin. The profile of action of ketanserin and spiperone in the rabbit aorta is consistent with the view that 5-HT2 receptors mediate contraction in this preparation. However, the 5-HT receptor mediating contraction in the dog saphenous vein appears to be '5-HT1-like', sharing a number of characteristics with the 5-HT1 recognition site identified from [3H]-5-HT ligand binding studies in brain tissue.

Germination and growth of Glomus caledonius spores: The effects of inhibitors and nutrients

Abstract: Spores of the vesicular-arbuscular mycorrhizal endophyte Glomus caledonius (Nicol. and Gerd.) Trappe and Gerdemann readily germinated in the absence of soil or host roots. Hyphal growth was improved by incorporation of nutrients into the medium and by the addition of pieces of cotyledon from boiled seeds, but was still dependent on the spore reserves. The response of ungerminated and pregerminated spores to inhibitors of protein and nucleic acid synthesis (cycloheximide, actinomycin D, proflavine hemisulphate, 5-fluorouracil and ethidium bromide) resembled those of saprophytic fungi more than other obligate biotrophs.