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Having identified prostaglandin receptors in trigeminal tissue, the functional effects of prostaglandin receptor ligands on CGRP release were investigated using cultured adult rat trigeminal ganglion neurones as a model system. It was found that calcium-dependent CGRP release could be stimulated following stimulation of DP, EP and IP receptors. Furthermore, the use of EP receptor specific agonists and antagonists suggested that the EP receptor subtype involved might be the EP2 receptor. The effects of several agents on prostaglandin E2 (PGE2) release from the cultured rat trigeminal neurones were also evaluated. From these data it was concluded that PGE2 itself could be released in a p42/p44 MAP kinase and protein kinase C-dependent manner following treatment with the algesic peptide, bradykinin, but not after depolarisation or treatment with either capsaicin or CGRP. Finally, superfusion studies were conducted to measure CGRP release from TNC slices in vitro. In this experimental model it was found that calcium-dependent CGRP release was stimulated by depolarisation and capsaicin treatment. Furthermore, evidence was obtained to suggest that although exogenous prostaglandins did not cause CGRP release per se in this system, they were able to modulate chemically stimulated CGRP release. In summary, this study has shown: (1) the presence of EP and IP prostanoid receptors in rat trigeminal ganglia, (2) that CGRP is released from cultured trigeminal neurones following DP, EP and IP receptor activation, (3) that PGE2 is released by bradykinin from the same neuronal cultures and (4) that CGRP release from TNC neurones is also prostaglandin-sensitive. Taken together, these data provide further evidence for important roles of both prostaglandins and CGRP in the pathophysiology of migraine headache.

This thesis examines the combustion of coal-oil slurries in the unusual low-recirculation conditions obtaining in the blast furnace tuyere raceway. A computer-controlled combustion rig was built which would simulate, as nearly as possible, the conditions of air velocity (typically 200 m/s) air preheat temperature (typically 1000°c) and oxygen enrichment (up to 26% oxygen content by volume) obtaining on a modern blast furnace. The results from this rig were used to calibrate a mathematical model of the mixing and combustion processes taking place. A theory of atomisation is proposed whereby the smaller coal particles are retained within the larger oil droplets, leaving the larger coal particles to combust separately. Using error analysis of the mathematical model, the size of coal particle which can remain within an oil droplet was found to have a ratio of less than 0.14. The apparatus was not as accurate in the delivery of slurry as it was in the delivery of preheated, oxygenated air. The total accuracy was found to have a 95% probability of less than 10% error. The mathematical model, however, was found to have a 95% probability of less than 5% error. When the work of other investigations - into the degree of recirculation obtaining in the tuyere raceway - is complete, the model will provide a satisfactory basis for prediction of maximum injection rates of coal-oil slurries into the tuyeres of a blast furnace, given the conditions of air blast obtaining.