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In 50 adult necropsies, measurements of linear dimensions and volume of the normal pituitary gland were correlated with corresponding measurements of the sella turcica obtained from radiographs. Though the female pituitary gland was significantly larger than the male, there was no significant sex difference in sellar size. Dimensions of gland and fossa were correlated separately for each sex. Correlation between gland volume and estimated sellar volume was good. The length of the sella and the width of its floor correlated well with the length and-width of the gland, but correlation between measurements of sellar height and gland height was poor, especially in women. Detailed studies of the radiological anatomy of these glands and fossae showed wide variation in the configuration of the diaphragma sellae, particularly in the position of its central portion relative to bony landmarks. In several a sub-diaphragmatic extension of the subarachnoid space was found. The shape of the gland varied markedly and was frequently distorted by compression by the carotid arteries. Bony configuration was also altered by these arteries which in some cases eroded the lateral margins of the dorsum sellae, undercutting the posterior clinoid processes. Some other variations in sellar contour are illustrated and discussed. To evaluate radiological criteria of abnormality in the light of such wide normal variation, radiographs of the pituitary fossa of 140 acromegalic patients were assessed. Over half were grossly abnormal, showing marked bony erosion and enlargement. In a quarter, a double sellar contour was present, but, since dimensions of the inner contour were normal or only slightly enlarged, abnormality was often overlooked. The remainder (18%) presented particular diagnostic difficulty. On plain films, commonly accepted criteria of abnormality discriminated poorly between this group and controls. Measurement of sellar dimensions, because of the wide normal range, was also unhelpful. However, tomography of the sella demonstrated significant abnormality in almost all and frequently revealed downward extension of the pituitary tumour unsuspected on plain films. Combined assessment by plain films and tomography showed sellar abnormality in nearly 99% of the 140 patients. To demonstrate suprasellar anatomy, tomography in two planes was combined with pneumoencephalography in 37 patients suffering from various types of pituitary tumour. Examinations were successful in all but one, showing a wide variation in the position of the superior aspect of the tumour. Suprasellar extensions were not predictable on the basis of bony configuration of the sella and frequently failed to produce visual field defects. Subarachnoid extensions into the sella were also demonstrated. Attention is drawn to the implications of these variations and the importance of their demonstration before therapeutic procedures on the pituitary gland are undertaken.

Problem The purpose of this research was to analyze the preparation and certification of industrial arts teachers in Canada and to devise a recommended program for industrial arts teacher education for Manitoba. A solution to this problem was sought through an examination of the problems of teacher preparation in Canada, certification practices, and industrial arts teacher preparation programs and recommendations in line with the best practices available were made. Procedure Data were collected, tabulated, and analyzed from various sources, including teachers, teacher-educators, and department of education officials throughout Canada by means of correspondence, consultation, and the review of pertinent documents. The teacher preparation systems of the provinces of Manitoba and Alberta were selected for more detailed study on the availability of information and because they afforded typical examples of the two major approaches to industrial teacher education. Information was also obtained from teachers in the provinces of Alberta and Manitoba as well as teacher-educators and other officials by means of an opinionnaire. A one-way analysis of variance and the Dunn's "c" test were used in making a comparison between the groups reporting. Results and Conclusions This research was intended to provide descriptive data of existing conditions in the preparation and certification of industrial arts teachers in Canada with the assumption that the information obtained would facilitate further research. Some of the more significant results of this research lie in the thinking and practices of those engaged in teacher education. For example, the findings of the study indicated that almost general agree ment existed among the three major groups involved in teacher educa tion, i.e . teacher-educators, teachers, and department of education officials, on the need for a basic four-year program of teacher education for both academic and industrial arts teachers. An analysis of the data further revealed that there was a great deal of similarity in all the pre-service programs conducted by provincial universities for teachers, apart, that is, from the area of specialty. Approximately one third of the total time allotment of these university- centered programs was required for general education studies for teachers of general academic subjects and industrial arts alike. In the available data related to department of education teacher- preparation courses it was noted that professional studies and skill training absorbed the majority of the required teacher preparation period. However, the value of many department of education courses is recog nized throughout Canada, and, accordingly, most universities allow them partial credit towards a degree standing. The certification of teachers in Canada remains solely a preroga tive of the respective provincial governments. This provision has remained relatively unchanged since the passing of the British North American Act of 1867. However, there is a pronounced trend in Canada to place all forms of teacher education in the hands of the provincial universities and other indications of consultation and cooperation between governmental officials, trustees' organizations and members of the teaching profession in respect to certification and preparation. Other conclusions drawn from this study were that the requirements for teacher certification in the various provinces of Canada present a somewhat confused and conflicting picture as each province appears to have different entrance requirements, periods of preparation, and certi ficate nomenclature. A four-year teacher preparation curriculum was recommended for industrial arts teachers in Manitoba based upon a comparison of exist ing programs in Canada with those suggested by leading educators in the area of industrial arts. Of all the industrial arts programs analyzed in this study, that of the province of Alberta appeared more nearly to meet the general education, the professional, and the concentration requirements of a well-balanced teacher education program.

This thesis presents optical measurements used to explore nanophotonic circuits composed of III-V semiconductors with embedded quantum dots. The focus of this work is to investigate issues related to the scalability and performance of these structures. A technique to register the position of a quantum dot, relative to pre-fabricated registration markers, with the aid of a solid immersion lens, is developed. The variance in the repeatedly registered position of the quantum dot is shown to be significantly reduced as a result of the solid immersion lens, compared with positions registered without a solid immersion lens. The total error of the deterministic fabrication, using position registered quantum dots, is small when compared to the size of optical fields. Confirmation of this has been achieved through two independent methods. Re-registration of the position relative to deterministically positioned registration markers show that the total error of deterministic fabrication is small. Additionally, the demonstration of optical spin readout, via the deterministic positioning of a quantum dot at a chiral point of a suspended nanobeam waveguide, further confirms the positional accuracy of the technique. The demonstration of efficiently coupled single photons form an embedded quantum into a nanobeam waveguide, with enhanced coherence lengths due to resonant excitation, is achieved. A high level of resonant laser rejection is demonstrated due to the orthogonal excitation and waveguide propagation directions.

This thesis describes experiments using optically detected nuclear magnetic resonance (NMR) techniques to probe and control the nuclear spin bath evolution in single self-assembled InGaAs quantum dots at large external magnetic fields. Strong non-resonant optical pumping is used to create spin bath polarisations ≳ 60% in dynamic nuclear polarisation. Changes of the nuclear magnetisation under resonant radio frequency (rf) excitation of nuclear Zeeman transitions are detected in low-power photoluminescence spectroscopy measurements of the hyperfine shifts of the exciton transition lines. Continuous wave rf excitation shows strong inhomogeneous broadening of the NMR spectra in a quantum dot owing to strain-induced quadrupolar interactions. Hahn echo measurements reveal comparatively long nuclear spin phase memory times T^HE_ M,n ~ 1-4 ms which are attributed to strong suppression of nuclear spin fluctuations due to the inhomogeneous broadening. Further progress towards full control of the spin bath evolution is made using a set of new multiple pulse NMR sequences combining features of Hahn and solid echoes. Measurements demonstrate that spin bath coherence times of up to ~ 20 ms can be achieved within the experimental limitations of this work. Use of these NMR sequences in combination with electron/hole spin control techniques is expected to increase central spin coherence times significantly. The equilibrium spin bath coherence properties are probed using a novel, weakly-invasive rf frequency comb NMR method. Frequency combs with varying tooth spacing are used to determine the homogeneous NMR lineshapes. The sensitivity of the homogeneous linewidths to fluctuations in the spin bath is used to probe the bath dynamics. Few-second-long spin flip-flop correlation times are revealed, demonstrating the potential of self-assembled InGaAs quantum dots to serve as a highly stable host system for spin qubits.