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The aims of this work were first to synthesize and fully characterize compounds that may function as bleomycin analogues and, second, to test their anticancer activity in vitro. Three novel tetradentate O,N,N,O Schiff base ligands, H₃L¹, H₂L³ and H₂L³ were synthesized by condensation of three different 1,3-diaminoalkane bridging units with two equivalents of (2,4-dihydroxy–phenyl)-(phenyl)methanone. These ligands contain two neutral imine nitrogen donors and two anionic phenolate oxygen donors for the coordination of metal ions. The choice of ligand was guided by the fact that Cu(II) bleomycin analogues with ligands employing O,N,N,O donor atom sets are able to cleave double-stranded DNA via oxygen radical formation. Using these ligands, six novel metal complexes of copper(II), nickel(II) and zinc(II) were synthesized and fully characterised. Two novel ligand crystal structures and six novel metal complex crystal structures are reported in this work. The X-ray structures of the two structurally characterized nickel(II) complexes [Ni(L²)] and [Ni(L³)] adopted the same nominally square planar coordination geometry, with the metal ion bound by the pairs of imine nitrogen and ortho-phenolic oxygen atoms of the ligand’s tetradentate donor atom set. The Ni–N and Ni–O distances averaged 1.892(3) Å and 1.845(2) Å, respectively. However, when reacted with Cu(II) and Zn(II), the ligands favored the formation of multinuclear complexes as a result of metal ion bridging by ionized oxygen donor atoms (either the phenolic oxygen atoms or an alkoxide oxygen atom of the 2-hydroxy substituted alkane bridge in the case of H₃L¹) of the polyfunctional ligands. For the di- and trinuclear copper(II) complexes, the mean Cu–N and Cu–O distances averaged 1.953(3) Å and 2.082(3) Å, respectively. For the dinuclear zinc(II) complex, the mean Zn–N and Zn–O distances averaged 2.074(3) Å and 2.042(3) Å, respectively. Electron spin resonance (ESR) measurements on the paramagnetic trinuclear copper(II) complexes confirmed that the trinuclear solid state structures remain intact in fluid solution (DMF) and that two of the three copper(II) ions are antiferromagnetically coupled, leaving the third as an S = ½ center with a hyperfine coupling constant to the I = 3/2 Cu nucleus of 14.80 G. Super-hyperfine coupling (15.13 G) to two N atoms was also evident, consistent with one of the terminal copper(II) centers (O,N,N,O donor atom set) being the site of the unpaired spin density in the molecule. Density functional theory (DFT) simulations were used to determine the electronic structures of the diamagnetic mononuclear nickel(II) complexes. The simulations reproduced the structures of [Ni(L²)] and [Ni(L³)] accurately with similarity coefficients for the two complexes of 0.982 and 0.990, respectively. The simulated electronic spectra (TD-DFT) of the nickel(II) complexes showed reasonably good agreement with the experimental spectra and were useful for the assignment of the low-lying MLCT state (near 400 nm) for the complexes as well as the higher-lying π-π* transitions between 300–350 nm. All of the metal complexes and one ligand were sent to MINTEK¹ (Project AuTEK) for anticancer screening. The copper(II) complexes (bleomycin analogues capable of generating hydroxyl radicals in vivo) showed significant cytotoxicity against the human cancer cell lines A549, DU145, HT-29, and U21. The trinuclear complexes were the most cytotoxic with mean IC₅₀ values of 6(2) and 7(1) μM for [Cu₃(L²)₂Cl₂(DMF)₂] and [Cu₃(L³)₂(H₂O)₂]Cl₂, respectively. The nickel(II) complexes [Ni(L²)] and [Ni(L³)] were comparatively inactive with mean IC₅₀ values of >50 and 35(16) μM, respectively, consistent with the fact that they do not readily generate reactive oxygen species in a cellular environment. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Transition metal oxide thin films are commonly used in organic electronics devices to improve charge-injection between electrodes and organic semiconductors. Some oxides are good hole-injectors, while others are good electron-injectors. Transition metal oxides are materials with many diverse properties. Many transition metals have more than one stable oxidation state and can form more than one oxide. Each oxide possesses its own unique properties. For example, transition metal oxide electronic band structures can range from insulating to conducting. They can exhibit a wide range of work functions. Some oxides are inert, while others are catalytically active. Such properties are affected by numerous factors, including cation oxidation state and multiple types of defects. Currently it is not fully understood which oxide properties are the most important to their performance in organic electronics. In the present thesis, photoemission spectroscopy is used to examine how changes in certain oxide properties–such as cation oxidation states and defects—are linked to the oxide properties that are relevant to organic electronics devices—such as an oxide’s work function and electron band structure. In order to unravel correlations between these properties, we controllably change one property and measure how it changes affects another property. By performing such tests on a wide range of diverse transition metal oxides, we can discern broadly-applicable relationships. We establish a relationship between cation oxidation state, work functions and valence band structures. We determine that an oxide’s electron chemical potential relative to an organic’s donor and acceptor levels governs energy-level alignment at oxide organic interfaces. We establish how interfacial reactivity at electrode/oxide interfaces dictates an oxide’s work function and electronic structure near the interface. iii These findings demonstrate some of the very interesting fundamental relationships that exist between chemical and electronic properties at interfaces. These findings should assist in the future development and understanding of the functional interfaces of organic semiconductors and transition-metal oxides.

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Paper One: An investigation of the social competence of pre-school children within three pre-school settings Abstract This paper is the first of two that investigates the concept of social competence in pre-school children within their pre-school and as they move onto their first year at school. Research has identified the development of social and emotional skills as key to a child’s future well being. Using a social constructionist perspective (Vygotsky, 1978; Rogoff, 1990), this project aimed to identify how pre-schools develop children’s social competence. Twenty-one children were observed in their free choice time at pre-school. Systematic observations recorded child-to-child activity and naturalistic observations recorded the children’s interactions with the adults present. Semi-structured interviews took place with the managers of the pre-schools. There were distinct beliefs amongst the pre-schools about how children’s social competence should be promoted. The observations revealed that the pre-school children were ‘sociable’ either by attaching to an adult or a peer. Adults were also communicative with the children within the ‘free choice’ periods but this was characterised by brief interactions with a broad content of making a request, ensuring a health and safety criteria was met rather than in sustained communication about play. It was concluded that pre-school practitioners may benefit from better targeted training to develop their skills in facilitating children’s social competence within play and that parental input could play a part in developing this. Paper 2 A case study of four children’s social competence during their transition from pre-school to Primary school Abstract This study undertook an examination of four children’s social competences during a period of 18 months while they experienced the transition from pre-school to Primary school. Transition has been described as a time of ‘discontinuity’ (Margetts, 2002). Using Bronfennbrenner’s (1979) ecological framework, there was a focus on the interactions of the child during transition as well as on the school level of influence. The data was explored using a case study approach; the play experiences of four children were recorded using two types of observation (both systematic and naturalistic), semi-structured interviews with pre-school and school staff were conducted and questionnaire data using the Social Competence Behaviour Evaluation, Pre-school edition (LaFreniere and Dumas, 2003) was taken from parents and teachers. In this study, schools had differing approaches to transition and there were found to be gaps in the transition process for children who had had no prior contact with the school. Social competence did not change over transition, except for a dramatic decrease in parent scores for two children. It was argued that children may benefit from more individualised approaches during transition and also better communication between pre-school settings and Primary schools.

This thesis is concerned with the experiences and understandings of young people as they move from their final two years of compulsory education into a range of post-16 destinations including Further Education, work, apprenticeships and unemployment. The participants were all identified as being ‘hard to reach’ by school practitioners. The research responds to a need to deepen understanding of such young people ahead of the age of participation in education and training in England being raised to 18 in 2015. The research was conducted in the South West of England. The empirical research was undertaken between January 2008 and April 2010 and comprised semi-structured interviews with 51 young people who were interviewed between one and three times during that period. The data presented in this thesis is focused on 11 of those young people who were each interviewed on three occasions. The findings suggest similarities between the post-16 transition experiences of the young people participating here and those of young people in this age range, not identified as ‘hard to reach’. Notwithstanding these parallels, the research revealed that young peoples’ post-16 transitions and the aspirations they hold are often more nuanced than has been theorised in previous research. The findings raise questions about the implications of labelling young people, and 14-19 policy predicated upon assumptions regarding those who do not participate post-16. In conclusion it is suggested that at a time of continued economic uncertainty and UK youth unemployment approaching one million , young people need more flexibility in the school and post-16 experiences that are available and actively encouraged, rather than increased levels of constraint.

Approved for public release; distribution is unlimited / This thesis examines the movement of personnel into, through, and out of the enlisted forces of the U.S. military services during the period FY1974-FY1987. The vehicle for this analysis is the Enlisted Transition Matrix, which is used by DOD and the Office of Management and Budget (OMB), to track the transition characteristics of the enlisted forces. The Matrix data were supplied by the Defense Manpower Data Center, Monterey, CA. The data were aggregated to the service-wide and years-of-service (YOS) level. The main conclusion of this thesis is that analysis of data aggregated to this level does not yield useful information. Economic and demographic factors fluctuated significantly during the period of interest; however, the effects of those fluctuations are not evidenced in enlisted force information aggregated to the force or YOS level. / http://archive.org/details/trendsinenlisted00good / Lieutenant Commander, United States Navy

Esa obra explora las complejidades de la economía y la sociedad cubana ahora, después de las reformas económicas dramáticas de 2012. El fenómeno de la fuga de cerebros refleja un cambio dramático en la economía cubana, en que los salarios públicos y otros subsidios del gobierno ya no están suficientes y los trabajos lucrativos no necesariamente requieren un título avanzado. En un país conocido internacionalmente por su población educado, Cuba tiene una crisis demográfica en que muchas profesionales, particularmente los jóvenes educados, salen del sector público al sector privado o aún emigran del país. El sector privado da una ventaja a algunas personas, también, cuando algunos grupos marginados están desventajados en términos económicos. Para restaurar y proteger la esencia del socialismo cubano, que prometa un nivel de vida básica y la igualdad de oportunidades por las instituciones, el gobierno debe implementar algunas reformas educativas y económicas. El gobierno puede asegurar un futuro para los ideales del socialismo cubano por esas reformas. El crecimiento económico, si es inclusivo, puede lograr los objetivos del socialismo cubano aún mejor que el sistema económico del pasado, y tiene el potencio para mejorar el nivel de vida de todos los cubanos.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.