Recrossing the Sargasso Sea: Trauma, Edward Kamau Brathwaite, and his Critics

In an oft-cited passage in his 1974 monograph Contradictory Omens, Kamau Brathwaite declared that white creoles had forfeited their claim to the spiritual life of the Caribbean. Whether intended or not, his pronouncement had the effect of raising doubts about the standing of Jean Rhys’s Wide Sargasso Sea (1966) in the Caribbean canon. In the ensuing debate, Brathwaite brought discomfiting attention to his own “received identity” as he termed it, as well as to that of the novel’s author and several prominent scholars who had written about it. The dialogs of misrecognition that have characterized several of the more notable exchanges between Brathwaite and his principal critic, Peter Hulme, illustrate the need for a reading practice for Caribbean trauma texts that recognizes, drawing on Cathy Caruth’s work, that authors and critics are implicated in each other’s histories. This recognition is particularly urgent in the case of critics that see themselves as connected to the historical traumas staged in a text that they are investigating. Rather than following the model of canonical European trauma texts, especially those set in the Holocaust, in which perpetrators and victims are opposed in both individual and collective binaries, Caribbean texts offer more complex sites for the study of trauma literature. Victims may be identified with groups that have perpetrated pervasive cultural trauma; and perpetrators of psychological trauma may belong to groups of the dispossessed. These crosscurrents provide highly productive grounds for deepening our understanding of the responses of readers and critics to trauma texts—and to each other

Atomic cluster state build up with macroscopic heralding

We describe a measurement-based state preparation scheme for the efficient build up of cluster states in atom-cavity systems. As in a recent proposal for the generation of maximally entangled atom pairs [Metz et al., Phys. Rev. Lett. 97, 040503 (2006)], we use an electron shelving technique to avoid the necessity for the detection of single photons. Instead, the successful fusion of smaller into larger clusters is heralded by an easy-to-detect macroscopic fluorescence signal. High fidelities are achieved even in the vicinity of the bad cavity limit and are essentially independent of the concrete size of the system parameters.Comment: 14 pages, 12 figures; minor changes, mainly clarification

THE TRAUMA OF THE CARIBBEAN TEXT: ETHICS AND PROBLEMS OF VICTIMIZERS AND VICTIMS, AUTHORS AND READERS

Since the early 1990s, trauma theory has acquired paradigmatic status as a methodology for studying literary representations of victims of various forms of violence, oppression, and social upheavals. However, with a genealogical foundation in Freud and an empirical basis in the Holocaust, trauma studies have been Eurocentric in orientation. My project seeks to “decolonize” trauma by bringing contemporary psychological and cultural trauma theory to bear on postwar Caribbean literature. Conversely, I use the insights provided by my investigation to reassess certain of the central tenets of trauma theory. I argue that in canonical Caribbean trauma texts, including Jean Rhys’ Wide Sargasso Sea, and Mary Chauvet’s Amour, Colère et Folie [Love, Anger, Madness], characters may be understood best as positioned at the intersection of psychological and cultural trauma theories. Victims of traumatic violence may be members of groups that have perpetrated violence on others; and perpetrators of violence may identify with groups that have been historically victimized. Viewing characters along a psychological trauma axis as individuals, and a cultural trauma axis as members of collectivities with which they identify, opens a range of new intepretive possibilities, and illuminates the manner in which critics respond to trauma texts and to each other. Trauma literature places extraordinary demands on writers and readers who, through empathetic identification with victims, are exposed to potentially destabilizing representations of victimization that transmit something of the experience of the original trauma. I propose a reading practice for Caribbean trauma literature that urges critical readers to maintain an ethical awareness of their own responses to scenes of traumatic violence so as to read the characters of both victims and perpetrators in their full complexity. This work includes an extended case study of the literature that emerged from the January 2010 earthquake in Haiti, supplemented by interviews of prominent Haitian authors that I conducted in Port-au-Prince in 2012-2013. Haitian earthquake texts and testimony tend to undermine significant Freudian-derived assumptions of modern trauma theory, including the doctrine of “unspeakability.” I sought in my readings of Haitian earthquake literature to identify a template of common thematic elements and distinct discursive modes that characterize these writings

Robust Entanglement through Macroscopic Quantum Jumps

We propose an entanglement generation scheme that requires neither the coherent evolution of a quantum system nor the detection of single photons. Instead, the desired state is heralded by a {\em macroscopic} quantum jump. Macroscopic quantum jumps manifest themselves as a random telegraph signal with long intervals of intense fluorescence (light periods) interrupted by the complete absence of photons (dark periods). Here we show that a system of two atoms trapped inside an optical cavity can be designed such that a dark period prepares the atoms in a maximally entangled ground state. Achieving fidelities above 0.9 is possible even when the single-atom cooperativity parameter C is as low as 10 and when using a photon detector with an efficiency as low as eta = 0.2.Comment: 5 pages, 4 figures, more detailed discussion of underlying physical effect, references update

Macroscopic quantum jumps and entangled state preparation

Recently we predicted a random blinking, i.e. macroscopic quantum jumps, in the fluorescence of a laser-driven atom-cavity system [Metz et al., Phys. Rev. Lett. 97, 040503 (2006)]. Here we analyse the dynamics underlying this effect in detail and show its robustness against parameter fluctuations. Whenever the fluorescence of the system stops, a macroscopic dark period occurs and the atoms are shelved in a maximally entangled ground state. The described setup can therefore be used for the controlled generation of entanglement. Finite photon detector efficiencies do not affect the success rate of the state preparation, which is triggered upon the observation of a macroscopic fluorescence signal. High fidelities can be achieved even in the vicinity of the bad cavity limit due to the inherent role of dissipation in the jump process.Comment: 14 pages, 12 figures, proof of the robustness of the state preparation against parameter fluctuations added, figure replace

Deep learning guided image-based droplet sorting for on-demand selection and analysis of single cells and 3D cell cultures.

Uncovering the heterogeneity of cellular populations and multicellular constructs is a long-standing goal in fields ranging from antimicrobial resistance to cancer research. Emerging technology platforms such as droplet microfluidics hold the promise to decipher such heterogeneities at ultra-high-throughput. However, there is a lack of methods able to rapidly identify and isolate single cells or 3D cell cultures. Here we demonstrate that deep neural networks can accurately classify single droplet images in real-time based on the presence and number of micro-objects including single mammalian cells and multicellular spheroids. This approach also enables the identification of specific objects within mixtures of objects of different types and sizes. The training sets for the neural networks consisted of a few hundred images manually picked and augmented to up to thousands of images per training class. Training required less than 10 minutes using a single GPU, and yielded accuracies of over 90% for single mammalian cell identification. Crucially, the same model could be used to classify different types of objects such as polystyrene spheres, polyacrylamide beads and MCF-7 cells. We applied the developed method for the selection of 3D cell cultures generated with Hek293FT cells encapsulated in agarose gel beads, highlighting the potential of the technology for the selection of objects with a high diversity of visual appearances. The real-time sorting of single droplets was in-line with droplet generation and occurred at rates up to 40 per second independently of image size up to 480 × 480 pixels. The presented microfluidic device also enabled storage of sorted droplets to allow for downstream analyses

Peroxisome motility measurement and quantification assay

Organelle movement, distribution and interaction contribute to the organisation of the eukaryotic cell. Peroxisomes are multifunctional organelles which contribute to cellular lipid metabolism and ROS homeostasis. They distribute uniformly in mammalian cells and move along microtubules via kinesin and dynein motors. Their metabolic cooperation with mitochondria and the endoplasmic reticulum (ER) is essential for the β-oxidation of fatty acids and the synthesis of myelin lipids and polyunsaturated fatty acids. A key assay to assess peroxisome motility in mammalian cells is the expression of a fluorescent fusion protein with a peroxisomal targeting signal (e.g., GFP-PTS1), which targets the peroxisomal matrix and allows live-cell imaging of peroxisomes. Here, we first present a protocol for the transfection of cultured mammalian cells with the peroxisomal marker EGFP-SKL to observe peroxisomes in living cells. This approach has revealed different motile behaviour of peroxisomes and novel insight into peroxisomal membrane dynamics (Rapp et al., 1996; Wiemer et al., 1997; Schrader et al., 2000). We then present a protocol which combines the live-cell approach with peroxisome motility measurements and quantification of peroxisome dynamics in mammalian cells. More recently, we used this approach to demonstrate that peroxisome motility and displacement is increased when a molecular tether, which associates peroxisomes with the ER, is lost (Costello et al., 2017b). Silencing of the peroxisomal acyl-CoA binding domain protein ACBD5, which interacts with ER-localised VAPB, increased peroxisome movement in skin fibroblasts, indicating that membrane contact sites can modulate organelle distribution and motility. The protocols described can be adapted to other cell types and organelles to measure and quantify organelle movement under different experimental conditions

The agronomy jigsaw: Finding the pieces that maximise water use efficiency

The Agronomy Jigsaw project is an initiative of the Department of Agriculture and Food, Western Australia (DAFWA) in collaboration with the South East Premium Wheat Growers Association (SEPWA) and Precision Agronomics Australia (PAA). The Grains Research and Development Corporation (GRDC) funded the project under the water use efficiency initiative (DAW193). Improving water use efficiency (WUE) is the key to increasing crop production in dryland agriculture. In southern Western Australia (WA), water use efficiencies of wheat can vary from 8 to 22kg/mm/ha. The purpose of the Agronomy Jigsaw project is to understand this variation at paddock level: What are the main causes of this variability and how can we manage it to improve profitability?https://researchlibrary.agric.wa.gov.au/bulletins/1268/thumbnail.jp