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Individuals have widely differing radiosensitivities as shown in the G2 radiosensitivity experiments in blood lymphocytes from conditions such as breast cancer and ataxia telangiectasia (AT) (Sanford et al 1989, Scott et al 1994, 1996)). This study investigated whether there was a correlation in colour switch ratio (the number of colour-switch breaks/total number of breaks) and radio sensitivity in breast cancer and normal surgical controls and in an AT and normal lymphoblastoid cell line. Harlequin-stained cells were subjected to the G2 assay and the number of chromatid breaks in the light and dark strands and colour-switch breaks were scored in 100 cells per sample. The mean csr in breast cancer patients was 25.8% compared to a mean of 15.9% in control patients indicating a, significant difference; P= 0.0024. The mean radiosensitivity (which was expressed as the frequency of chromatid breaks/100 cells) in breast cancer patients (56.2) was also significantly higher than the mean radio sensitivity in control patients (27.9); P= 0.0000. When csr was plotted against radiosensitivity, two separate cohorts were produced - one for breast cancer individuals and a second for control individuals suggesting a possible use in breast cancer screening. In the AT cell line, however, the mean csr was 29% compared to the mean of 26% in the normal control cell line. There was thus no significant difference in csr between the AT and normal cell line; P= 0.13. It might be expected that as AT individuals are hypersensitive to ionising radiation (as indicated by the higher number of chromatid damage), they might (if csr was related to radiosensitivity) have a significantly higher csr than normal or breast cancer patients. From the results presented, however, this appears not to be the , case. The results indicate that csr and radiosensitivity are not always correlated. Thus the results show that although csr and radiosensitivity are not always correlated in the AT cell line investigated, when radiosensitivity was plotted against csr, the breast cancer cohort appeared to separate from the control patients. It was very interesting to observe that in this study, all of the breast cancer individuals were discriminated by this correlation of high csr and radiosensitivity in comparison to normal control individuals. If this correlation is confirmed in several more studies, this predictive test has the potential to be used as an assay to detect individuals predisposed to breast cancer. If it discriminates almost all of the breast cancer cases as my experiments showed, then this could prove to be a more valuable and accurate assay than the G2 assay which has been shown to discriminate 42% radiosensitive breast cancer patients (Scott et al 1994).

One issue has dominated the majority of historical studies of Restoration Scotland, that of religious dissent. Robert Wodrow's The Sufferings of the Church of Scotland from the Restoration to the Revolution portrayed an age of brutality in which the people were involved in a godly struggle in defence of Presbyterianism with an administration intent on maintaining Episcopal Church government. Wodrow's version of events has come to dominate the bulk of previous research, and few political studies of the period have been attempted. The Scottish Parliament, its role and function during the reign of Charles II has been particularly neglected. This thesis attempts to redress this state of affairs and provide a detailed account of Parliament during the period. The thesis proceeds chronologically, with an initial chapter on the first session of the Restoration Parliament. The transition from the republican regime to restored monarchy is examined, and the Restoration settlement, the constitutional basis of government during the period, is studied in detail. The second chapter on the parliamentary sessions of 1662 and 1663 begins to examine the personalities of the administration, and discusses the factional divisions that play out in the theatre of Parliament. Following chapters on the Conventions of Estates of 1665, 1667 and 1678 study the effect of religious dissent on the fiscal fortunes of the crown. The growth of an increasingly effective parliamentary opposition is considered in a series of chapters on the Parliament of 1669-1674 and on the session of 1681, the last of Charles II's reign. This thesis attempts to challenge the notion that Parliament in the Restoration era was merely a submissive body, easily moulded to the royal will. Instead, it is argued that the restrictions on parliamentary freedoms in the settlement of 1661 combined with the increasingly authoritarian administration of John Maitland, second Earl (later first Duke) of Lauderdale, created a body of opposition that believed Parliament had a substantial role to play. That such opposition existed sheds new lights on later events, particularly the deposition of the Stewart monarchy.

A theoretical study of the pulsation of Delta Scuti stars is presented. A modified Henyey code is used to produce a grid of evolutionary models of population I composition, spanning the area of the Instability Strip on and near the Main Sequence (mass range 1.4 to 3.0 Mₒ ; log T > 3.8). Linear pulsation analysis of these models is carried out, using both adiabatic (Sturm Sequence) and non-adiabatic techniques. The results are found to agree closely, and to be consistent with the observed properties of real stars. A number of the models are subjected to non-linear analysis, using a modified Christy hydrodynamic code and the Carson opacities. A series of models is given an initial velocity kick of surface amplitude 10 km/s and profile varying as the fifth power of the fractional radius. The light curves of these models are found to be dominated by the fundamental mode and first harmonic. The first five eigenfunctions produced by the Sturm Sequence method are used as initial velocity profiles for another series of models, again with an initial kick of 10 km/s. The light curves of these models are found to be dominated by the frequency corresponding to the initially imposed mode of pulsation. For both sets of models, the light amplitudes are found to be larger than those of real stars. However, the indication of a number of criteria is that the models have not settled down to a final (smaller) amplitude. The first three Sturm Sequence eigenfunctions are used as initial velocity profiles for a smaller set of models with an initial kick of surface amplitude 3 km/s. Again, a final, settled amplitude is not achieved, but amplitudes are closer to those of real stars. The shapes of the light and velocity curves correspond closely to those of the same models with the larger kick. It is suggested that the form of the light curve may depend on the mode of pulsation. An attempt to use the shape of the light curves of real stars as a diagnostic for the mode of pulsation is unsuccessful, due to lack of data in the literature. A number of models depleted of helium are studied. One set has (X,Y,Z) = (0.88,0.10,0.02). The opacity table for this composition is obtained by interpolating between the Carson tables C312 and C402. The second set has (X,Y,Z) = (0.98,0.00,0.02), corresponding to table C402. Both sets of models continue to pulsate, and it is concluded that the region of hydrogen ionisation is an important source of driving in these stars.

1. The inhibitory effect of glucosone on yeast fermentation was shown to the specific for the D-isomer, and exerted at some point before the breakdown of fructose-1:6-diphosphate. 2. The results of the fermentation experiments are analysed, kinetically, and glucosone shown to be a pseudo-irreversible inhibitor, of the type described by Ackermann and Potter (1949). It is shown that the effects produced by glucosone in animals can be correlated vd.th this finding. 3. The osone is shown to be phosphorylated by ATP in the presence of hexokinase. 4. It is suggested that the inhibitory effect produced by glucosone on yeast fermentation, is due to the slow dissociation of a glucosone phosphate from the hexokinase molecule. 5. The effect of hexokinase on a number of glucose analogues is reported, and indications are given of the high degree of specificity exhibited by the enzyme. 6. Methods are described for the preparation of an actively fermenting acetone-dried extract, and a maceration juice, from 'bakers' yeast. The preparation and some properties of cold-treated bakers' yeast are also described. 7. A method is described for the separation of the substrates .and products of the hexokinase reaction, on paper chromatograms.

1. A technique for the introduction of substances into the cerebellum of the decerebrate rabbit was developed and the effects of drugs and brain extracts on the electrical activity of the cerebellum were studied using this method. 2. Extracts of cerebellar tissue were found to increase the electrical activity of the cerebellum and this action could not be attributed to Ach, histamine or to any other identified pharmacologically-active constituent of the nervous system, nor could it be attributed to a vascular action. The activity was not detected in similar concentrations in extracts of cerebral hemispheres or upper brain-stem. 3. The physical and chemical properties of the cerebellar excitatory substance were studied and attempts to purify it from crude brain extracts were made. 4. The enzymic destruction of the active factor was demonstrated and this destruction was shown to be inhibited by small amounts of strychnine. The active substance was found to be released from the cerebellum under various conditions of stimulation. 5. The active substance had no apparent effect on any of the common pharmecological preparations, not did it affect transmission at the neuromuscular junction and superior cervical ganglion. 6. The cerebellar factor was found to affect spinal reflexes and the electrical activity of the cerebral cortex. 7. Nervous tissue from six animal species was found to contain the active substance, but it was not detected in similar concentrations in tissues outside the nervous system. Its distribution in various regions of the nervous system of the dog was shown to bear an approximately inverse relationship to the distribution of choline acetylase activity and acetylcholine. 8. It has been suggested that the cerebellar factor has some claims to be considered as a non-colinergic transmitter of nerve impulses and experiments which might eventually confirm this hypothesis have been considered.

In this thesis, the behaviour of Kelvin-Helmholtz unstable modes on the magnetospheric flanks and in the magnetotail are investigated. A model of a straight bounded magnetosphere connected to a semi-infinite field-free magnetosheath which is flowing with a uniform speed is used. First the magnetosphere is taken to be uniform with the magnetic field perpendicular to the flow in the magnetosheath and it is shown that the increase in Pc5 wave power observed for high solar wind flow speeds correlates well with the onset of instability of the fast body modes. A condition for the exact onset of instability of these modes is derived and the behaviour of fast surface and slow body and surface modes is also investigated. Using a non-uniform magnetosphere, it is shown that these unstable body modes may couple to field line resonances. The fastest growing modes are found to have a common azimuthal phase speed which depends only on the local conditions at the magnetopause and may be predicted using the theory of over-reflection. A finite width boundary layer is then added to the uniform magnetosphere model to investigate the space-time evolution of wave-packets on the magnetopause. Fast surface mode wave-packets are found to grow rapidly as they convect around the flanks so that non-linear effects will be important. Fast cavity mode wave-packets will remain relatively small on the flanks, explaining the robustness of the body of the magnetosphere here. Slow modes are found to grow very little in this region. Finally, a uniform magnetosphere with the magnetic field parallel to the flow in the magnetosheath is considered. Here, the fast modes are unlikely to be Kelvin-Helmholtz unstable for realistic flow speeds, and the magnetopause boundary may be reasonably assumed to be perfectly reflecting. The low value of the plasma pressure is this region suggests that slow modes will be unimportant.

Pressure application of gamma-aminobutyric acid (GABA) to mouse spinal and rat DBG neurones maintained in culture evoked transient membrane currents. Using the whole-cell patch clamp technique, these currents were shown to primarily involve the flow of Cl-. The GABA-evoked whole-cell currents in both types of neurones were reversibly suppressed by the GABAA antagonist bicuculline. The barbiturate phenobarbitone reversibly potentiated GABA-evoked whole-cell currents in mouse spinal neurones. Attempts to look at the unitary currents activated by GABA in outside-out patches, revealed spontaneous unitary currents. The I-V relationships of the spontaneous currents were linear and had a reversal potential of OmV in symmetrically distributed Cl solutions. Changing the monovalent cation concentrations on one or both sides of the membrane patch had no effect on the amplitude or the reversal potential of the spontaneous currents. Replacing some of the Cl- in the patch pipette with the impermeant anion SO42- shifted the reversal potential to more negative values. These spontaneous currents in both types of neurones were blocked by bath perfusion of bicuculline. GABA-activated unitary currents in outside-out patches, the main conductance state in both types of neurones was 30pS. However, GABA could occasionally also activate other conductance levels. Spontaneous Cl- currents did not occur in cell-attached patches from mouse spinal and rat DRG neurones, suggesting that the spontaneous events in the outside-out patches did not represent the activity of voltage dependent Cl- channels. Alphaxalone, a steroid anaesthetic, potentiated GABA-evoked whole cell currents in both spinal and DRG neurones. At high (muM) concentrations, pressure application of alphaxalone evoked a membrane Cl- current; this current was reversibly suppressed by blcuculline and potentiated by phenobarbitone. Pregnanolone (5beta-pregnane-3x-ol-20-one) a progesterone metabolite at low (nM) concentrations reversibly enhanced GABA currents in spinal neurones. Pregnanolone at higher concentrations pressure applied to spinal neurones had a weak direct agonist action on the GABAA receptor. Pregnanolone prolonged the burst duration of GABA-activated unitary currents in outside-out patches from spinal neurones. Some of the actions of the steroids on the GABAA receptor were very similar to the barbiturates, bemegride, a respiratory stimulant was formerly used clinically to counteract barbiturate poisoning in man. Experiments were conducted to see whether bemegride could be used as a specific barbiturate antagonist. Bemegride reduced phenobarbitone enhanced GABA currents in mouse spinal neurones. However, bemegride alone also reduced GABA and pentobarbitone evoked currants to a similar extent. This is suggestive of a noncompetitive action on the GABAA receptor, therefore it was not used to elucidate the site of action of steroids.

Present knowledge indicates the importance of one region of monkey temporal association cortex, the superior temporal sulcus (STS), in predominantly high level analysis of 'biologically' important objects. To clarify and elaborate on the function of the monkey STS, the following questions are addressed: (1) what kind of tactile processing occurs in the polymodal STS and does it compare with the complex visual processing observed; (2) does behavioural sensitivity to face and body information parallel neural sensitivity (of STS cells) to the same stimulus dimensions; (3) does monkey STS ablation result in a behavioural indication of impairments in the perception of socially relevant stimuli; and (4) are visual cells in the STS sensitive to social communicational elements of facial or postural expression? Single-unit recording studies of the macaque STS (using standard techniques in awake, behaving animals) reveal a population of somatosensory neurones, with large receptive fields, sensitive only to unexpected (unpredictable) tactile stimulation. Complex tactual-visual interactions observed stress the importance of this dimension of processing. A separate population of visual cells exhibit sensitivity to compound facial expressions and head/body postures important in primate social communication. A behavioural study of monkeys' socio-emotional responses to configurational aspects of faces, the posture of the head and the interaction of form and motion, reveal their ability to discriminate salient cues in the context of social communication/interaction. It is tentatively shown that monkeys with the STS ablated are unable to make such discriminations, so reacting inappropriately to the stimuli (a symptom of Kluver-Bucy syndrome). The combined findings show that the STS performs a multimodal perceptual analysis of socially relevant stimuli, and suggest that the STS provides a sensory input to a limbic structure, such as the amygdala, through which it mediates appropriate emotional reactive behaviour.

Solar flares and solar prominences are amongst the best known features of solar activity. Despite this familiarity, however, there are still significant gaps in our knowledge of these phenomena. In this thesis some theoretical aspects of these events are considered. We first consider solar prominences. We propose a model for the static equilibrium of quiescent prominences which will simultaneously explain the support mechanism for the dense prominence material and take account roughly of the required energy balance. This model contains two parameters, namely the coronal plasma beta and the horizontal shear angle Φ, that the magnetic fieldlines make with the prominence normal. We obtain limits on both these parameters which, when exceeded, imply that no equilibrium state is possible. The results obtained provide a possible explanation for several prominence features. For the remainder of the thesis we consider one aspect of the solar flare problem, namely the possibility of a trigger mechanism for the rapid release of energy in a flare. One candidate for this mechanism is the sudden release of energy stored in excess of potential by a force-free magnetic field which becomes unstable as a result of photospheric motions. For this reason we seek simple analytic solutions to the force-free field equations which may exhibit such an instability. An alternative trigger mechanism, which requires the presence of a current sheet, is given by the emerging flux model for solar flares. We thus develop a one-dimensional model for current sheets in general, where the conditions within the current sheet are given in terms of several non-dimensional parameters which describe the external conditions. These results are then applied to the emerging flux model.