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Following a NEA high priority nuclear data request, an experimental campaign to measure the prompt Î3-ray emissions from 235 U has been performed. This has used the STEFF spectrometer at the new Experimental Area 2 (EAR2) within the neutron time- of-flight facility (n_TOF), a white neutron source facility at CERN with energies from thermal to approximately 1 GeV. Prior to the experimental campaign, STEFF has been optimised for the environment of EAR2. The experimental hall features a high background Î3-ray rate, due to the nature of the spallation neutron source. Thus an investigation into reduction of the background Î3-ray rate, encountered by the NaI(Tl) detector array of STEFF, has been carried out. This has been via simulations using the simulation package FLUKA. Various materials and shielding geometries have been investigated but the effects determined to be insufficient in reducing the background rate by a meaningful amount. The NaI(Tl) detectors have been modified to improve their performance in a high count rate environment, and their behaviour characterised to understand the response to higher count rates. Initial testing demonstrated that the modified detectors maintain a potential to measure Î3-ray multiplicities up to 3 counts per microsecond. However, the energy resolution fails somewhere below 1.75 counts per microsecond. The experimental campaign has produced a large amount of data. The preliminary analysis of phase one data has considered incoming neutron energies ranging from thermal to an upper limit of 1 eV, with a minimum Î3-ray energy threshold of 160 keV. Results have been achieved for the prompt fission Î3-ray multiplicity and total energy of M Î3 = 6.3 ± 0.2 and E S,Î3 = 9.0 ± 0.1 MeV respectively. Further work is ongoing by the STEFF team at Manchester to improve upon these results and analyse the remainder of the data set at higher incoming neutron energies.

This thesis focuses on the development of new biocatalytic strategies as a contemporary solution to synthetic design. Here we have put to use the unique regio-, stereo- and/or chemoselectivity offered by biocatalysts to develop synthetically attractive routes to enantiopure materials. The first chapter discusses the development of a transaminase triggered aza-Michael cascade towards the synthesis of enantioenriched 2,6-disubstituted piperidines in good yield with >99% e.e. and >99% d.e. This methodology utilises a favourable spontaneous intramolecular aza-Michael reaction (IMAMR) to drive the reversible enzymatic transformation towards the formation of cyclic products, thus removing the need for additional approaches to displace the reaction equilibrium towards product formation. The alkaloid, (-)-pinidinone, was synthesised in three steps on a 0.5 g scale and a range of analogues was also successfully prepared to demonstrate the scope of the reaction. The reversible transamination reaction in combination with the thermodynamically favourable IMAMR, forming a stable cyclic product, results in a regioselective transamination of (3E)-dec-3-ene-2,8-dione. This inspired us to develop an amino donor and acceptor substrate that was successfully transaminated to form pinidinone with no external source of amine. The second chapter discusses the synthesis of novel bis-conjugated enones and their subsequent transamination to provide bicyclic alkaloids via double aza-Michael additions. However, under the tested reaction conditions, the TA reaction resulted in complete decomposition of all but two of the tested substrates. 1-Methyldecahydropyrrolo[1,2-a]quinolin-5(1H)-one was produced as three isomers whose relative stereochemistry was assigned by NMR. Interestingly, transamination of (2E)-1-(cyclohex-1-en-1-yl)oct-2-ene-1,7-dione provided 1-(cyclohex-1-en-1-yl)-2-[(2S,6S)-6-methylpiperidin-2-yl]ethanone as the major product and an inseparable mixture of 1-methyldodecahydro-6H-pyrido[1,2-a]quinolin-6-one isomers as the minor product. Initiating the second IMAMR of 1-(cyclohex-1-en-1-yl)-2-[(2S,6S)-6-methylpiperidin-2-yl]ethanone was attempted. The epimerisation of 1-methyldecahydropyrrolo[1,2-a]quinolin-5(1H)-one and 1-methyldodecahydro-6H-pyrido[1,2-a]quinolin-6-one proved unproductive. The third chapter investigates the synthesis of 2-alkyl-3-(4-oxopentyl)cyclohex-2-en-1-one and their subsequent use in a TA-IMAMR cascade towards the pragmatic synthesis of the natural product histrionicotoxin (HTX) and its derivatives. A Baylis-Hillman reaction was optimised for the insertion of the α-alkyl substituent into the cyclohexanone scaffolds. TA conditions were found to convert the unsubstituted scaffold to provide (2S)-2-methyl-1-azaspiro[5.5]undecan-8-one as a 1:1 mixture of diastereoisomers. The optimal epimerisation conditions found provided a 3:1 mixture of diastereoisomers, however, isolation of the compounds proved unsuccessful. Reduction of the carbonyl to provide the core HTX structure was tested. This provided an inseparable mixture of products. Under the biocatalytic reaction conditions, the IMAMR of 2-ethyl-3-(4-oxopentyl)cyclohex-2-en-1-one provided 3-[(4S)-4-aminopentyl]-2-ethylcyclohex-2-en-1-one as the major product. This is due to the (2S)-7-ethyl-2-methyl-1-azaspiro[5.5]undecan-8-one being an unfavourable product, which is in agreement with current literature.

The past decade has seen a significant increase in the number of autistic students attending mainstream educational provision. Improving outcomes for this group is a complex issue given the deficit of evidence based practice within schools. A mixed methods multiple case study design was used to evaluate the impact and outcomes of a new peer mentoring programme targeting the inclusion of autistic students. Twelve autistic students and thirty-six non-autistic students participated as mentors across five mainstream secondary schools in the South East of England. Semi-structured interviews were used to record the views and experiences of the mentors and staff participating in the programme. Autistic mentors completed questionnaires on levels of social satisfaction, bullying and social competence. All showed improvements over the course of the programme. These findings highlight the importance of the full inclusion of autistic students in peer mentoring programmes and the use of approaches promoting social competence. The study has wider implications on the way educational approaches for autistic students are developed and implemented in mainstream secondary schools.

This thesis identifies and elucidates a common engagement with Mesopotamian kingship ideology in the Gilgamesh and the Alexander the Great narrative traditions. As both archetypal monarchs are understood to have ruled as kings in Mesopotamia, this is a much more secure context for comparison. The result of this contextualisation is that the identified parallels are better supported and more clearly understood. Although the study is rendered in comparison, the exegesis of the episodes is not strictly bound by parallels between the traditions. The primary concern is a comparable engagement with Mesopotamian kingship ideology. This enables the thesis to contribute uniquely to the study of each figure’s kingship, as well as their comparative dynamic. Mesopotamian kingship was a contest, and our two subject kings represent rivals for the pinnacle in this arena. Therefore, the identification and presentation of a king to surpass all others is argued for both in presented deeds and persevering legends. Chapter one outlines the premise of the thesis, addresses previous comparisons made in scholarship between the subject kings, and discusses the evidence. Specifically, this is the network of narratives utilised by the study. For the Gilgamesh tradition, these are the Akkadian language manuscripts of the Gilgamesh Epic and the Sumerian Gilgamesh poems concerning the death of Gilgamesh and his campaign against Huwawa. For the Alexander tradition, the study is limited to the Alexander narratives that share a relative geographically congruence with the Gilgamesh narratives. These are the canonical Graeco-Roman Alexander narratives by Diodorus, Curtius, Plutarch, Arrian, and Justin, as well as the Pseudo-Callisthenes narratives, the Syriac Alexander Legend and the Syriac Metric Homily. Chapter two outlines the methodology. Chapter three contextualises Gilgamesh’s campaign against Humbaba in Mesopotamian kingly action. Chapter four argues for a comparative understanding of Alexander’s siege of Tyre. Chapter five then compares the death of a king in each tradition, and chapter six the subsequent mythical wanderings of our protagonist kings. Chapter seven provides the thesis’ conclusion. The overarching themes are the legitimisation of one’s kingship and the transfer of power in the Mesopotamian royal tradition.

Continental breakup within the Afar triple junction makes it an ideal location to investigate the response of the mantle and lithosphere to rifting and elevated mantle potential temperatures. Many factors have been proposed as being important to the initiation and development of rifting including mantle potential temperature, mantle composition, melt focusing, prior rift history and active upwelling. Rayleigh-wave tomography is used to construct a 3-dimensional shear wave velocity model and to produce a model of azimuthal anisotropy divided into 6 areas for the upper 250 kilometres beneath the Afar triple junction. Also presented are shear wave splitting results from along the northern and southern margins of the Gulf of Aden. Low shear wave velocities are interpreted as partial melt segmented beneath the rifts. The distribution of melt is indicative of buoyancy driven active upwelling suggesting that mantle segmentation observed at oceanic spreading centres initiates early during continental rifting. Across the majority of the continental areas, crustal anisotropy is orientated NE-SW and attributed to pre-existing Pan African basement foliation. Lithospheric anisotropy for rifted areas is rift parallel and likely due to magmatic intrusion and aligned partial melt with negligible lithospheric anisotropy in Afar and the plateaux. Asthenospheric anisotropy throughout the whole region ranges from N-S to NE-SW which is interpreted as being due to mantle flow associated with the African Superplume. Shear wave splitting results from the Gulf of Aden margins are generally null which can be explained by widespread vertical mantle flow due to small scale convection. Limited shear wave splitting is recorded and likely occurs at the edge of the African LLSVP in the lower mantle. Thus the style of rifting in Afar Triple Junction can be attributed to the elevated mantle potential temperatures of the African Superplume in addition to melt focusing and active upwelling due to the lithospheric topography of the rifts.