Search Results - "Challis, A.J."

Design of Helix Pitch Profile for Broadband Traveling-Wave Tubes by Ghosh, T.K., Challis, A.J., Jacob, A., Bowler, D.

“…To improve the performance of a broadband traveling-wave tube (TWT), a helix pitch profile incorporating a section with reduced phase velocity followed by a…”
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Improvements in Performance of Broadband Helix Traveling-Wave Tubes by Ghosh, T.K., Challis, A.J., Jacob, A., Bowler, D., Carter, R.G.

“…The effectiveness of positive phase velocity tapering to improve the performance of a broadband helix traveling-wave tube (TWT) has been investigated. A…”
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Optimization of Coaxial Couplers by Ghosh, T.K., Carter, R.G., Challis, A.J., Rushbrook, K., Bowler, D.

“…A simple and accurate method has been developed to optimize the performance of coaxial couplers for traveling-wave tubes using a 3-D electromagnetic field…”
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Evolution of multi-octave helix traveling wave tubes by Challis, A.J., Ghosh, T.K., Tokeley, A., Rushbrook, K., Poston, I., Jacob, A.

“…Increasing demands of system integrators and designers, on efficiency and increased capability, have lead to a requirement for higher RF power levels and…”
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Optimization of helix pitch profile for broadband Mini-TWTs by Ghosh, T.K., Jacob, A., Tokeley, A., Rushbrook, K., Poston, I., Challis, A.J., Bowler, D.

“…Broadband helix traveling-wave tubes (TWTs) with a pitch profile incorporating a section of reduced phase velocity followed by a positive taper show…”
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Improvements in Broadband Performance of Mini-TWTs at e2v technologies by Ghosh, T.K., Challis, A.J., Tokeley, A., Rushbrook, K., Poston, I., Matthews, R., Jacob, A., Bowler, D.

“…Positive phase velocity tapering has been implemented to improve the broadband performance of helix traveling wave tubes (TWTs). The slow wave structures of a…”
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Modulation of muscarinic cholinoceptor-stimulated inositol 1,4,5-trisphosphate accumulation by N-methyl-D-aspartate in neonatal rat cerebral cortex by Challis, R A, Mistry, R, Gray, D W, Nahorski, S R

“…The mechanisms by which N-methyl-D-aspartate (NMDA) receptor activation can modulate muscarinic receptor-stimulated phosphoinositide turnover have been studied…”
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Comparison of methods to assess cyclic AMP turnover under conditions of agonist stimulation in 1321N1 astrocytoma cells by Morgan, A J, Murray, K J, Challiss, R A

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Effects of an adenosine-receptor antagonist on insulin-resistance in soleus muscle from obese Zucker rats by Challis, R.A.J, Budohoski,L, McManus, B, Newsholme, E.A

“…The decreased sensitivity of glycolysis to insulin seen in isolated soleus muscles from genetically obese Zucker rats was abolished by addition of the…”
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The rate of substrate cycling between fructose 6-phosphate and fructose 1,6-bisphosphate in skeletal muscle from cold-exposed, hyperthyroid or acutely exercised rats by Challis, R A, Arch, J R, Newsholme, E A

“…The effects of cold-exposure, the hyperthyroid state and a single exercise bout in vivo on the maximal enzyme activities of 6-phosphofructokinase and…”
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Effects of starvation on the maximal activities of some glycolytic and citric acid-cycle enzymes and glutaminase in mucosa of the small intestine of the rat by Budohoski, L, Challis, R A, Newsholme, E A

“…Starvation decreases activities of some glycolytic and citric acid-cycle enzymes, and increases those of glucose 6-phosphatase and fructose bisphosphatase,…”
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