Group theoretic methods in elementary particle physics

Imperial Users onl

Building Unity Through State Narratives: The Evolving British Media Discourse During World War II, 1939-1941

The British media discourse evolved during the first two years of World War II, as state narratives and censorship began taking a more prominent role. I trace this shift through an examination of newspapers from three British regions during this period, including London, the Southwest, and the North. My research demonstrates that at the start of the war, the press featured early unity in support of the British war effort, with some regional variation. As the war progressed, old political and geographical divergences came to the forefront in coverage of events such as Prime Minister Chamberlain\u27s resignation. The government became increasingly concerned about the grim portrayals of the Dunkirk Evacuation in the press, as Britain\u27s wartime situation deteriorated. I argue that as censorship and propaganda increased, newspapers fell into line, adhering to state narratives and uniting behind a circumscribed version of the events that molded a heroic presentation of Dunkirk. Censorship from the government came in various forms, often utilizing softer methods such as the control of information flow and warning publications, which complied in order to appear patriotic and avoid further suppression. My analysis of these papers indicates that this censorship and unity of the press continued during coverage of the Blitz, as the media discourse became more cohesive and supportive of the government\u27s goals

South Africa's cataract surgery rates – why are we not meeting our targets?

Cataract is the leading cause of blindness in South Africa, responsible for about 50% of the prevalence of blindness1 and identified as a national health priority. The cataract surgery rate (CSR) should be at least 2 000 per million population per year for elimination of cataract blindness. The national CSR target was planned to increase from 1 000 in 2005 to 2 000 in 2010, but since CSRs have failed to reach targets each year, the national target for 2010 was reduced from 2 000 to 1 500. We reviewed data from a situational analysis in 2007 of cataract surgery services to ascertain the obstacles to achieving CSR targets

Structural Investigation of Bacilliredoxins: Enzymes Involved in Bacillithiol Redox Metabolism

Bacillithiol is an important compound involved in intracellular redox homeostasis and fosfomycin resistance mechanisms of some Gram-positive bacterial pathogens. Cellular regeneration of active bacillithiol (BSH) from a disulfide (BSSB) or mixed disulfide state (BSS-Protein) involves the bacilliredoxin enzymes BrxA/B. An X-ray crystallographic structure of apo BrxA from Bacillus subtilis has been previously characterized, but no BrxB or BSSB-bound Brx structure currently exists. Here we present an X-ray crystallographic structure of BrxA from the pathogen Staphylococcus aureus with a bacillithiol disulfide (BSSB) bound in the active site. Elucidation of this structure will help researchers to understand how BSSB binds in bacilliredoxins, and provide insight into the Brx catalytic mechanism. Functional activity of YpdA, another enzyme involved in BSH regeneration, is also investigated

Managing information in eye care programmes: the health systems perspective

As eye care workers, we don’t treat eyes, we treat people. Similarly, eye care does not take place in a vacuum; it is part of the wider health care system

OXYGEN DELIVERY BY OUTGASSING OF HYPERBARICALLY LOADED MICROTANKS AND BULK POLYMERS FOR BIOMEDICAL APPLICATIONS

Oxygen diffusion limitations within nascent tissue engineering scaffolds leads to the development of hypoxic regions, cell death, and graft failure. Diffusion limitations are most severe in scaling from the mm-sized grafts studied in rodents to the cm-sized grafts required for human patients and thus represent a major barrier to clinical translation. Extensive efforts have been made to delivery oxygen within tissue engineering scaffolds to help maintain cell viability during the period of vascular development and anastomosis. Unfortunately, the approaches that have been developed which include peroxide-doping, perfluorocarbons, hyperbaric oxygen therapy have lacked cytocompatability, oxygen capacity, and practicality, respectively. The outgassing of oxygen from hyperbarically loaded polymers represents a novel and elegant solution that addresses these shortcomings. Many commonly used biocompatible polymers possess high resistance to oxygen diffusion but a non-trivial solubility of oxygen (on the order of 10% V/V/atm). Thus it is possible to load the polymer with oxygen gas using a hyperbaric chamber and to subsequently achieve a prolonged delivery of oxygen as the polymer outgasses. By forming microscopic polymeric shells with a hollow core, the loading efficiency of oxygen can be greatly enhanced and such a structure is termed a microtank. In this thesis, we will describe the development and empirical validation of the theory governing the oxygen delivery from hyperbarically loaded materials, including microtanks. Oxygen loaded microtanks and/or bulk polymers can be combined with a hydrogel phase to form a scaffold with oxygen delivery throughout. This oxygen delivery approach has been shown to enhance the survival of human cells cultured under anoxic conditions for out to 6 days. Beyond tissue engineering, hyperbaric oxygen loading could be used to functionalize many clinically used polymer implants such as screws, suture anchors, stiches, etc. as elevated local oxygen tensions have been shown to enhance collagen deposition and reduce infection. Indeed, the biomedical applications are diverse and abundant