Constructing imperial mindsets: Race and development in Britain’s interwar African colonial administration

Very few have attempted to discuss interwar British colonial officials' intellectual interactions with the metropole in the early twentieth century. And yet such interactions are key if we are to really understand the way administrators understood race, imperial power and development. Where the ideas of colonial officials in interwar Africa have been examined, academics tend to coalesce around one of two arguments. Some believe that the British were cautious and conservative, which is said to account for the rise of the doctrine of 'indirect rule' and an aversion to the introduction of educational provision to thecontinent. Others, predominantly postcolonialists writing in the last twenty years or so, have argued that the British in Africa were ambiguous as to what their role was, because, they were attached to both ideas of the 'civilizing mission' and the 'noble savage.' In contrast to the first line of thinking, the British were in fact consistently interventionist, due to a moral universalism, a belief in the 'good' of the British, and an excited advocacy of the act of change. In contrast to the second line of thinking, the British genuinely felt that they were effecting coherent programmes of political, economic and social infrastructural development. The enthusiasm for change and a perception of Africa as robust and adaptable more than countered any sense of loss at the passing of a pre-colonial Africa that was usually depicted in negtive terms, especially when it was felt that what was good about 'traditional' African society could be preserved by indirect rule. The source of British confidence lay to a significant extent in the constant engagement of colonial officials with metropolitan ideas. Elite administrators, anthropologists and other commentators of the day all sanctioned the act of change. British conceptions of racial categories and imperial strength conjoined in such a way that officials felt that they were effecting coherent plans which blended both 'reform' and 'stasis' because both race and empire were felt considerably more robust than retrospective depictions of early-twentiethcentury fears over the validity of the 'civilizing mission' have deemed

EPR detection and characterisation of a paramagnetic Mo(III) dihydride intermediate involved in electrocatalytic hydrogen evolution

EPR spectroscopy and theoretical data show that the slow heterogeneous electron-transfer kinetics associated with the reduction of an 18-electron Mo(IV) acetato dihydride are a consequence of an η2−η1 rearrangement of the carboxylate ligand which gives a unique paramagnetic 17-electron Mo(III) dihydride

Intrinsic winding of braided vector fields in tubular subdomains

Braided vector fields on spatial subdomains which are homeomorphic to the cylinder play a crucial role in applications such as solar and plasma physics, relativistic astrophysics, fluid and vortex dynamics, elasticity, and bio-elasticity. Often the vector field's topology—the entanglement of its field lines—is non-trivial, and can play a significant role in the vector field's evolution. We present a complete topological characterisation of such vector fields (up to isotopy) using a quantity called field line winding. This measures the entanglement of each field line with all other field lines of the vector field, and may be defined for an arbitrary tubular subdomain by prescribing a minimally distorted coordinate system. We propose how to define such coordinates, and prove that the resulting field line winding distribution uniquely classifies the topology of a braided vector field. The field line winding is similar to the field line helicity considered previously for magnetic (solenoidal) fields, but is a more fundamental measure of the field line topology because it does not conflate linking information with field strength

Nitrosylation of nitric-oxide-sensing regulatory proteins containing [4Fe-4S] clusters gives rise to multiple iron-nitrosyl complexes

The reaction of protein-bound iron–sulfur (Fe-S) clusters with nitric oxide (NO) plays key roles in NO-mediated toxicity and signaling. Elucidation of the mechanism of the reaction of NO with DNA regulatory proteins that contain Fe-S clusters has been hampered by a lack of information about the nature of the iron-nitrosyl products formed. Herein, we report nuclear resonance vibrational spectroscopy (NRVS) and density functional theory (DFT) calculations that identify NO reaction products in WhiD and NsrR, regulatory proteins that use a [4Fe-4S] cluster to sense NO. This work reveals that nitrosylation yields multiple products structurally related to Roussin's Red Ester (RRE, [Fe2(NO)4(Cys)2]) and Roussin's Black Salt (RBS, [Fe4(NO)7S3]. In the latter case, the absence of 32S/34S shifts in the Fe−S region of the NRVS spectra suggest that a new species, Roussin's Black Ester (RBE), may be formed, in which one or more of the sulfide ligands is replaced by Cys thiolates

Computer modelling for the prediction and analysis of spectroscopic data: Application to lyotropic aggregates and transition metal centres

In this thesis Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations are used to predict, interpret and analyse a range of Electron Paramagnetic Resonance (EPR) and Nuclear Inelastic Scattering (NIS) spectra of di�erent molecular systems. By relating theory and experiment, the models are rigorously tested as well as enabling a clearer interpretation of complex spectra. Firstly, slow motion EPR spectra of microaggregate, micellar, hexagonal and lamellar lyotropic liquid crystal aggregations are investigated for two di�erent surfactant/water systems. Geometric parameters predicted from MD simulations, such as aggregate radii and eccentricity, are compared with experimental data and the dynamics investigated through the use of the Model-Free (MF) approach, allowing for prediction of EPR spectra using the Stochastic Liouville Equation (SLE) in order to relate dynamics and geometry. For the complex hexagonal and lamellar lineshapes, the MF-SLE predicted spectra are compared with those predicted directly and completely from MD. These techniques and simulation approaches are then expanded to the investigation of the structure and dynamics of spin labelled DNA. A scheme for rotation about triple bonds in MD is found to produce good agreement with the spectra observed for acetylene tethered spin labelled DNA using the new parmbsc1 force�eld. The geometry and magnetic parameters of two molybdenum complexes are calculated using DFT. The fast motion EPR spectra are then simulated using these parameters, thereby con�rming the proposed rearrangement of core geometry in the catalytic cycle. Finally, the NIS spectra of a range of iron-sulphur clusters are predicted using DFT for a series of model compounds and hypothetical structures and compared with available experimental spectra. This tests both the accuracy of DFT and the ability of NIS to discriminate between iron sulphur clusters, whilst additionally con�rming spectral assignments