Mark my words: an exhibition about marginalia

The book, The Ghost In The Fog has been included in an exhibition about marginalia in the Upper Library, The Queen's College Library, Oxford

Mathematical models of continuous flow electrophoresis: Electrophoresis technology

Two aspects of continuous flow electrophoresis were studied: (1) the structure of the flow field in continuous flow devices; and (2) the electrokinetic properties of suspended particles relevant to electrophoretic separations. Mathematical models were developed to describe flow structure and stability, with particular emphasis on effects due to buoyancy. To describe the fractionation of an arbitrary particulate sample by continuous flow electrophoresis, a general mathematical model was constructed. In this model, chamber dimensions, field strength, buffer composition, and other design variables can be altered at will to study their effects on resolution and throughput. All these mathematical models were implemented on a digital computer and the codes are available for general use. Experimental and theoretical work with particulate samples probed how particle mobility is related to buffer composition. It was found that ions on the surface of small particles are mobile, contrary to the widely accepted view. This influences particle mobility and suspension conductivity. A novel technique was used to measure the mobility of particles in concentrated suspensions

Measuring the Impact of Trade Finance on South African Export Flows

Trade finance (or short-term credit) plays a crucial role in facilitating international trade yet is particularly vulnerable to financial crises as banks increase the pricing on all trade finance transactions to cover increased funding costs and higher credit risks. Whereas South Africa’s financial institutions largely managed to strengthen their capital positions during the global financial crisis, the country’s trade flows and access to capital (in particular trade finance and its costs) were hit hard by the crisis. Little is known about the extent of shortages or ‘gaps’ in trade finance and the impact of this on South Africa’s recent trade performance. Whilst our research recognises that access to trade finance is not the main cause of South Africa’s trade contraction, our research suggests that a one percentage point increase in the interbank lending rate of our trade partner could reduce exports by approximately ten percent, all else equal.exports trade finance crisis

The development of socialist magic: reflections on the place of power and ideology in magic performance

The author seeks to establish a historical context for his own performance practice, which combines radical left politics with magic tricks and ventriloquism. A survey of the iconography of magic performance from the time of Jean Eugene Robert-Houdin onwards reveals an ideological underpinning which reflects hierarchies of class, gender and race in society. However, the magician’s role is complex, as he (or less commonly she) practises an art which is part of ‘low’ culture, despite its association with the rich and powerful. Moreover, the modern magician is associated with rationalism and scepticism, which sometimes puts the conjurer on the side of a progressive view of society. The author examines his own attempts to overcome this disjunction in his practice and explains why, for him, the combination of agitprop and magic performance can only be effective through the use of humour

Developing interest management techniques in distributed interactive simulation using Java

Bandwidth consumption in distributed real time simulation, or networked real time simulation, is a major problem as the number of participants and the sophistication of joint simulation exercises grow in size. The paper briefly reviews distributed real time simulation and bandwidth reduction techniques and introduces the Generic Runtime Infrastructure for Distributed Simulation (GRIDS) as a research architecture for studying such problems. GRIDS uses Java abstract classes to promote distributed services called thin agents, a novel approach to implementing distributed simulation services, such as user defined bandwidth reduction mechanisms, and to distributing the executable code across the simulation. Thin agents offer the advantages of traditional agents without the overhead imposed by mobility or continuous state, which are unnecessary in this context. We present our implementation and some predicted results from message reduction studies using thin agent

Fluid mechanics of continuous flow electrophoresis

The following aspects of continuous flow electrophoresis were studied: (1) flow and temperature fields; (2) hydrodynamic stability; (3) separation efficiency, and (4) characteristics of wide gap chambers (the SPAR apparatus). Simplified mathematical models were developed so as to furnish a basis for understanding the phenomena and comparison of different chambers and operating conditions. Studies of the hydrodynamic stability disclosed that a wide gap chamber may be particularly sensitive to axial temperature variations which could be due to uneven heating or cooling. The mathematical model of the separation process includes effects due to the axial velocity, electro-osmotic cross flow and electrophoretic migration, all including the effects of temperature dependent properties

Xylooligosaccharidesand Arabinoxylanoligosaccharides and Their Application as Prebiotics

Background and Objective: Xylooligosaccharides and arabinoxylanoligosaccharides have been subject to nearly 30 years of in vitro and clinical trials, and advances in process technology have led to more widespread commercial availability. This review was conducted to examine xylooligosaccharides and arabinoxylanoligosaccharides as next generation prebiotics.Results and Conclusion: Xylooligosaccharides and arabinoxylanoligosaccharides are based upon 5-carbon sugars, and their microbial utilization in the digestive tract is thus fundamentally different from prebiotics such as fructooligosaccharides, inulin, and resistant starch that are oligomers/polymers of 6-carbon sugars connected by α bonds. Five carbon sugars and oligosaccharides connected by β bonds are more narrowly utilized; xylooligosaccharides and arabinoxylanoligosaccharidesare especially effective for selective feeding of Bifidobacteria, although they can also be used by some strains of Lactobacilli and other bacteria. Clinical studies on xylooligosaccharides and arabinoxylanoligosaccharides report beneficial impacts upon digestive health, management of blood sugars and lipids, beneficial modification of immune markers, and benefits for laxation. These outcomes have typically been observed at 1-4 grams per day, a lower dose than required for other prebiotics such as fructooligosaccharides and inulin. The lower dose requirement for clinical efficacy also provides advantages in terms of product formulation and more options for delivery of a clinically beneficial dose to consumers

Functional Attributes and Health Benefits of Novel Prebiotic Oligosaccharides Derived from Xylan, Arabinan, and Mannan

Prebiotic oligosaccharides are produced from many different sources, with substantial differences in chemical structure, bonds between subunits, and degree of polymerization. These structural differences can materially affect microbial utilization and the dose required for efficacy. Most prebiotic oligosaccharides are based on subunits comprised of 6-carbon sugars such as glucose/fructose and alpha bonds. Newer/novel oligosaccharides are derived from 5 carbon sugars and/or connected via beta bonds. Clinical trials with xylooligosaccharides, arabinoxylanoligosaccharides, and mannooligosaccharides have shown improvements in lipids, cholesterol, management of blood glucose, weight management, and laxation, at doses typically ranging from 1 to 4 g per day. Mannooligosaccharides are also showing promise for animal health, with the potential to reduce antibiotic use. These novel prebiotics are showing promise due to greater selectivity and their ability to deliver health benefits at a lower dose compared to conventional prebiotics