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This thesis reports a study carried out to investigate the involvement of VA mycorrhizas in interplant 15N transfer in a model pasture system and in a model agroforestry system. Two pot experiments were designed to investigate the effect of VAM inoculation on 15N transfer from clover to rye grass in sterile (in the first experiment the sterilisation was by autoclaving and in the second, by gamma-irradiation) and fresh soil. A third pot experiment was designed to investigate the effect of VAM inoculation on 15N transfer from grass and clover to wild cherry seedlings in fresh soil. For these pot experiments donor plant seedlings were labelled with 15N by growing in Hoaglands solution containing K 15NO3 (5 atom % 15N). To study 15 N transfer and its possible mechanisms, plants and soil samples were analysed for 15N, total N (14N + 15N) and P concentrations. Rates of soil nitrogen mineralisation and nitrification, as well as 15N enrichment of available N were also determined to investigate N transfer through soil. There was transfer of 15N from donor to receiver in the simulated pasture system as well as in simulated agroforestry system. The transfer of 15N was increased by VAM inoculation. The transfer of 15N was small in relation to plant nutrition and was not associated with an increase in total N in the receiver plants although P concentrations were generally increased. There was no increase in the soil N fluxes of mineralisation and nitrification associated with enhanced 15N transfer from donor to receiver in the VAM inoculated system. In addition, there was often no increase in the 15N concentration in the soil available N pool of VAM inoculated systems. There was no evidence, therefore, of increased transfer of 15N through the soil in VAM inoculated systems with enhanced 15N interplant transfer, suggesting the likely involvement of VAM fungal hyphae. There was no marked effect on plant growth due to VAM inoculation. The growth of cherry, however, was reduced when grown with grass and this may have been due to N competition between the root systems. The growth of cherry seedlings was reduced to a lesser extent when grown with clover compared to when grown with grass. The findings of this study suggest that VA mycorrhizal hyphae play a part in interplant transfer of nitrogen. Although the study did not demonstrate high rates of 15N transfer in VAM inoculated system, circumstances are discussed where VAM interplant transfer of nutrients may become significant at the single plant, community and ecosystem level. The benefits to man of VAM mediated N transfer may be best realised in land use systems such as pastures having legumes and non-legumes, in mixed cropping of legumes and non-legumes and in an agroforestry system with a legume component, particularly when the soil is deficient in nutrients such as nitrogen and phosphorus.

The main hypothesis of this thesis was that the regulation of oxygen uptake (VO2) kinetics at the onset of exercise in trained young men is linked to cardiovascular adaptations. Two studies were conducted to investigate the interrelationships between oxygen (O2) transport and O2 utilization in accelerating VO2 kinetics at the onset of exercise. In the first study, simultaneous kinetics of VO2 and cardiac output (Q) were studied during the transition to heavy and moderate cycling exercise (Chapter 2). The acceleration of VO2 kinetics during the heavy exercise that followed prior moderate or heavy exercise was enabled by the rapid increase in Q; whereas, the acceleration of VO2 kinetics during moderate exercise that followed a heavy warm-up was associated with small changes in Q kinetics. The objective of the second study was to determine, in a model of forearm exercise, if the elevation of forearm blood flow (FBF) prior to the onset of exercise by prior circulatory occlusion would accelerate FBF and muscle oxygen uptake (VO2mus)kinetics during subsequent exercise as demonstrated previously for prior exercise (Chapter 3). Prolonged ischemia (15 min occlusion) followed by 3 min recovery reduced FBF and impaired VO2mus kinetics during subsequent heavy hand-grip exercise. However, prior heavy exercise confirmed the previous findings and resulted in a faster FBF and VO2mus kinetics. There was a high positive correlation between the time course of change in FBF and VO2mus at the onset heavy exercise. In a follow up of the second study, to investigate a possible mechanism for the slower adaptation of VO2mus following ischemia, the prior occlusion condition was repeated after ingesting a high dose of ibuprofen. Prostaglandin inhibition by ibuprofen augmented the FBF response during reactive hyperaemia and restored FBF during the heavy exercise that followed 15 min of circulatory occlusion to the control level. These two studies provide evidence that O2 delivery plays a dominant role in accelerating VO2 kinetics at the onset of heavy exercise in trained young men. The findings exposed differences in the mechanisms regulating pulmonary VO2 and VO2mus with prior exercise resulting in higher Q and FBF, but no changes in O2 extraction to yield the faster increase in pulmonary VO2 and VO2 at the onset of subsequent heavy exercise. In contrast, prior occlusion slightly retarded the increase in FBF and significantly reduced O2 extraction thus delaying VO2 kinetics. The precise mechanisms impairing VO2mus kinetics at the onset of heavy forearm hand-grip exercise that starts after a brief recovery from prolonged occlusion are still unknown, but this impairment may be partially due to a vasoconstrictor effect restricting blood flow during the adaptation to exercise and redistribution of the blood to the periphery. In a third study, the influence of muscle activity on the VO2 slow component during heavy exercise and O2 cost during moderate exercise that followed a heavy warm-up were examined (Chapter 4). The heavy exercise VO2 slow component was attenuated in a graded fashion by prior moderate and heavy warm-ups, and the principal components analysis showed a moderate but significant correlation between the changes in the integrated electromyographic activity and the VO2 slow component amplitude. The higher O2 cost of moderate exercise following a heavy warm-up was associated with higher mean power frequency. Changes in VO2 slow component and increased O2 cost during moderate exercise after prior heavy warm-up appear to be related to some changes in surface electromyographic activity which may provide some evidence for increased muscle fibres recruitment.

The main hypothesis of this thesis was that the regulation of oxygen uptake (VO2) kinetics at the onset of exercise in trained young men is linked to cardiovascular adaptations. Two studies were conducted to investigate the interrelationships between oxygen (O2) transport and O2 utilization in accelerating VO2 kinetics at the onset of exercise. In the first study, simultaneous kinetics of VO2 and cardiac output (Q) were studied during the transition to heavy and moderate cycling exercise (Chapter 2). The acceleration of VO2 kinetics during the heavy exercise that followed prior moderate or heavy exercise was enabled by the rapid increase in Q; whereas, the acceleration of VO2 kinetics during moderate exercise that followed a heavy warm-up was associated with small changes in Q kinetics. The objective of the second study was to determine, in a model of forearm exercise, if the elevation of forearm blood flow (FBF) prior to the onset of exercise by prior circulatory occlusion would accelerate FBF and muscle oxygen uptake (VO2mus)kinetics during subsequent exercise as demonstrated previously for prior exercise (Chapter 3). Prolonged ischemia (15 min occlusion) followed by 3 min recovery reduced FBF and impaired VO2mus kinetics during subsequent heavy hand-grip exercise. However, prior heavy exercise confirmed the previous findings and resulted in a faster FBF and VO2mus kinetics. There was a high positive correlation between the time course of change in FBF and VO2mus at the onset heavy exercise. In a follow up of the second study, to investigate a possible mechanism for the slower adaptation of VO2mus following ischemia, the prior occlusion condition was repeated after ingesting a high dose of ibuprofen. Prostaglandin inhibition by ibuprofen augmented the FBF response during reactive hyperaemia and restored FBF during the heavy exercise that followed 15 min of circulatory occlusion to the control level. These two studies provide evidence that O2 delivery plays a dominant role in accelerating VO2 kinetics at the onset of heavy exercise in trained young men. The findings exposed differences in the mechanisms regulating pulmonary VO2 and VO2mus with prior exercise resulting in higher Q and FBF, but no changes in O2 extraction to yield the faster increase in pulmonary VO2 and VO2 at the onset of subsequent heavy exercise. In contrast, prior occlusion slightly retarded the increase in FBF and significantly reduced O2 extraction thus delaying VO2 kinetics. The precise mechanisms impairing VO2mus kinetics at the onset of heavy forearm hand-grip exercise that starts after a brief recovery from prolonged occlusion are still unknown, but this impairment may be partially due to a vasoconstrictor effect restricting blood flow during the adaptation to exercise and redistribution of the blood to the periphery. In a third study, the influence of muscle activity on the VO2 slow component during heavy exercise and O2 cost during moderate exercise that followed a heavy warm-up were examined (Chapter 4). The heavy exercise VO2 slow component was attenuated in a graded fashion by prior moderate and heavy warm-ups, and the principal components analysis showed a moderate but significant correlation between the changes in the integrated electromyographic activity and the VO2 slow component amplitude. The higher O2 cost of moderate exercise following a heavy warm-up was associated with higher mean power frequency. Changes in VO2 slow component and increased O2 cost during moderate exercise after prior heavy warm-up appear to be related to some changes in surface electromyographic activity which may provide some evidence for increased muscle fibres recruitment.

Examining the process of knowledge exchange and uptake (KEU) involved collaborating with a current decision-maker to determine what knowledge would be examined to increase the understanding why evidence is accepted or rejected as evidence for decision-making. The knowledge selected were the organizational values of a Regional Health Authority from a managerial perspective. The uptake was how the values informed decision-making. The secondary attributes were identified as the conditions and characteristics that enable or challenge using values. As decision-makers prefer usable tools as a research deliverable, a Continuous Improvement Model and Logic Model were populated with the results of a mixed method inquiry. The actionable recommendations are intended to counter challenges and encourage best practices, and provide evaluation indicators. This dissertation will add to the growing literature on how to influence the uptake of evidence through collaboration and effective knowledge transfer plans that aid in bridging the know-do gap.

During, the Churchill Coalition, 1940-45, there developed within tile Government a coherent thesis that the Soviet Union would follow a post-war policy of cooperation with Britain. Soviet foreign policy-makers were perceived to have till-cc options; isolation, enmity or collaboration. Three central perceptions produced tile theory that cooperation was the likely choice. The first that developed, from 1940, was the view that Soviet aims were limited, largely defensive, and not likely to impinge upon areas of vital British interest. Far from desiring to propagwie world revolLitioii, Stalin simply wanted protection, particularly against a resurgent Germany, to continue the internal development of industrialization and state socialism interrupted by the war. After Barbarossa, the immense task of Soviet reconstruction became a second factor. Even if the USSR attempted to do this without foreign help, its rulers would seek tile cheapest possible foreign policy to enable them to coriccritratc on it: collective security in cooperation with Britain and possibly the USA. Third, Stalin was now secii iis it wise, realist statesman who had become persuaded of the wisdom of a cooperation policy will, the West. Linked with these assumptions were conclusions drawn from observations of changes in the USSR in the war, especially the revivill of nationalism, and from observation of the sensitivity of Soviet leaders. Debate on these percept ions and tile policy that should follow chiefly took place within the 1,0 departments, between thern and their ambassadors in Moscow and other places, with the military, and intermittently in Cabinet. Ilowevcr, while a policy combining "firmness" and "frankness" was preferred by most, considerations of Soviet sensitivity meant it wits never I'Llily implemented. Thus in February 1945, there was a rough consensus that [lie Soviets would try cooperation, but there was uncertainty as to the optimum British policy to maximise the chances of securing it.

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