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In the first study, functional brain networks are derived from magnetoencephalography (MEG) data from 12 healthy subjects in two task conditions (resting and finger tapping). The brain’s function is found to be characterized by a topological structure intermediate between random (short-cut connections) and highly ordered (provincial clustering). The architecture, as measured by a range of graph metrics, remains scale-invariant throughout the functioning brain’s classical frequency bands (from low frequency δ to high frequency γ) and in both the resting and motor states. Despite the general conservation of functional architecture, the brain does adjust the length of its high frequency (especially γ, >37.5 Hz) connections when it is required to perform a finger tapping task. The relatively shorter connections in the resting state suggest the existence of an energy efficiency constraint. In the second study, we therefore hypothesized that the brain functions on a balanced platform of maximum efficiency for minimum cost, and that the successfulness of this optimization predicts the cognitive ability of the system. Frequency specific functional networks were again derived from the MEG data of 28 healthy controls and 29 people with schizophrenia taken during a working memory task. A measure of the cost-efficiency of the high frequency (β band, 15-30 Hz) networks was found to be strongly predictive of a person’s cognitive performance independent of the health of the subject (whether non-psychotic or diagnosed with schizophrenia). In a third study, we used structural magnetic resonance imaging (sMRI) data from 259 healthy subjects and 203 people with schizophrenia to construct anatomical networks from the pairwise covariation of regional gray matter volumes. We found that the anatomical structure in the healthy brain contains a hierarchical organization which is inverted in schizophrenia and may thus be a vestige of abnormal neurodevelopmental processes.

All life depends upon water. For man, however, water can supply the power necessary to relieve him from the drudgeries of life and give the time and means to enrich his existence beyond the bounds set by the mere need to survive. Large scale hydropower makes a significant contribution to the total generated power of the developed world. The means of harnessing water power for large flows and heads above three metres are efficient and well established. There remains however, the fact that many people, especially in developing countries live adjacent to water courses and tidal estuaries where heads of 2 metres or less exist but are not exploited. The reasons for this are often that practical machines do not exist or are insufficiently well developed to be used. Much effort has been made in recent years to develop equipment suitable for small, low-head sites in remote places. The writer has worked on three such devices in both the laboratory and on site - these are the Salford Transverse Oscillator, the AUR Water Engine and the Underwater Motor. This thesis describes these machines in detail together with other contemporary devices. The initial chapter contains an assessment of machines used in the past to exploit low head sites. There is little doubt that some of these older machines, suitably brought up to date in design and materials, would be more suited to the needs of developing peoples than many of the esoteric devices described in later chapters. The thesis is concerned mainly with the need to provide a means of generating power rather than the assessment or suitability of a site for power generation. The writer draws on experience gained in the laboratory, and as a Mechanical Engineering Consultant for small installations in the United Kingdom and overseas.

The French Renaissance revival in British architecture, 1824-1914, is a history of the revival in secular and domestic architecture of a range of French historical styles (sixteenth- to eighteenth-century), for both interiors and exteriors, beginning with the revived Louis quatorze of the 1820s and ending with the Neo-Grec style, which was associated in the Edwardian era with the Beaux-Arts influence in architectural planning and composition, as well as in education and civic design. Between these extremes lay such revivals as the decorative Francois Premier and the Loire chateau styles; most wide-spread of all was the influence of the Louvre and the hotel de Ville of Paris. This broad scope is partly determined by the fact that architects tended to combine motifs from different periods in a single building, making the isolation of any one revived French style unrealistic, and partly by the continuity possessed by the movement as a whole which paralleled that of Victorian and Edwardian architecture generally. Within a basically chronological framework, the revival is described in its evolution away from a superficial concern for motifs unrelated to the building plan, towards the absorption of Beaux-Arts principles of homogeneous composition. At the same time an investigation of the reasons for the popularity of these particular styles suggests for them a more important role in Victorian architecture than is usually recognised. The sheer volume of output in itself demands attention; but it is argued that in another sense the French styles were literally central to Victorian architecture. Like the Queen Anne movement, with which they were closely allied, they were seen as a compromise between Gothic and Classic and therefore as a possible solution to the problem of a style truly appropriate to the nineteenth century. In addition to such theory, the thesis investigates the relationship (aesthetic and associational) between style and environment, including the reasons for the earlier appearance of the Loire style in Scotland than in England. Matters of patronage, politics, economics and materials are dealt with, while special attention is paid to the literature of the movement. The importance which many Victorians themselves attached to the French styles; the influence of Beaux-Arts principles upon modern architecture; and most of all the spirited excellence of certainin individual buildings make reappraisal of this movement overdue.