Evaluation of Next Generation Capillary-Channeled Polymer Fibers and the Implementation of C-CP Fiber Modification Modalities on Non-Fiber Substrates

Developing new stationary phases for liquid chromatography is continuing to drive high performance liquid chromatography (HPLC) into the future. In this regard the Marcus’ group has been leveraging the continued advances of Capillary-Channeled Polymer (C-CP) fibers in an attempt to meet the demand of high throughput biomarcomolecule chromatography. Separation mechanisms studied include: ion-exchange (IC), reversed phase (RP), affinity, hydrophobic interaction chromatography (HIC). In this work, the next generation of C-CP fiber stationary phases was thoroughly evaluated with respect to hydrodynamic concerns relating to protein chromatography. Traditionally C-CP fibers have eight channels that run co-linearly along the length of the fiber. Packed C-CP fibers form a network of pseudo-open capillary structures through channels interdigitating. The fibers studied have a much higher surface area to volume ratio compared to circular fibers with similar diameters. The open tubular network has an added bonus of operating at low back pressures. C-CP fibers are non-porous with regards to biomarcomolecules, resulting in fast mass transfer kinetics causing no significant C-term band broadening. The next generation of C-CP fiber has been developed with three larger more ridged channels. This design allows for tighter packing densities without compromising channel integrity. This advancement allows the fibers to operate at higher linear velocities leading to a separation of a six-protein suit (ribonuclease A, cytochrome C, lysozyme, transferrin, bovine serum albumin, and α-chimotrypsinogen) under reversed phase conditions. Surface modification of the C-CP fibers has been accomplished with a variety of techniques, both through covalent and physical adsorption modification. Of particular interest to this work is the Lipid Tethered Ligand (LTL) surface modification modality, which has seen excellent success when employed on polypropylene C-CP fibers. LTLs functionalize a surface with ion-exchange or affinity ligands through hydrophobic physical adsorption to augment the available surface chemistry in a quick and simple flow-through system. In the work presented here, the LTL system was applied to the most commonly used polymer resin, polystyrene-divinylbenzene. The effectiveness of LTL loading, stability, and kinetics on PS-DVB was evaluated. Ligand availability was evaluated with both biotin-LTL for the extraction of streptavidin and iminodiacetic acid-LTL for the extraction of methylene blue

The theatre of violence: narratives of protagonists in the South African conflict

This profound and deeply compassionate study aims to reach into the complexities of political violence in South Africa between 1960 and 1994, and to expand our understanding of the patterns of conflict that almost drew South Africans into a vortex of total disintegration during the apartheid era. This book is used in the teaching of critical and social psychology at both undergraduate and postgraduate levels. While many accounts have focused on the victims of state repression, this unique volume documents the often contradictory and confusing stories of those who acknowledge having committed some dreadful deeds. Individuals on various sides of the apartheid divide, from state security structures to the ANC, PAC and grassroots, activists, tell their own stories. The central focus is to give an account of the actions of the perpetrators, here depicted as competing protagonists in an arena of violence. It examines the violence forensically, through its public and popular representations, academically and, finally, through the narrative approach, drawing on a rich analysis of stories from different sides. The authors also offer the first critical examination of the TRC's amnesty process, show how media representations of perpetrators inform public perceptions, and scrutinise international scholarly writings on the issue of political violence. Suggestive and intriguing, The Theatre of Violence opens a fresh examination of the erstwhile taken-for-granted understandings and attempts to address a range of questions that are often not considered, and perhaps cannot be considered, in a dispassionate way. It is in many ways an optimistic study, holding out the possibility of a society that can understand and take steps to minimise the perpetration of gross violations of human rights