Writing Coastlines: Locating Narrative Resonance in Transatlantic Communications Networks

The term ‘writing coastlines’ implies a double meaning. The word ‘writing’ refers both to the act of writing and to that which is written. The act of writing translates aural, physical, mental and digital processes into marks, actions, utterances, and speech-acts. The intelligibility of that which is written is intertwined with both the context of its production and of its consumption. The term ‘writing coastlines’ may refer to writing about coastlines, but the coastlines themselves are also writing in so far as they are translating physical processes into marks and actions. Coastlines are the shifting terrains where land and water meet, always neither land nor water and always both. The physical processes enacted by waves and winds may result in marks and actions associated with both erosion and accretion. Writing coastlines are edges, ledges, legible lines caught in the double bind of simultaneously writing and erasing. These in-between places are liminal spaces – points of both departure and arrival, and sites of exchange. One coastline implies another, implores a far shore. The dialogue implied by this entreaty intrigues me. The coastlines of the United Kingdom and those of Atlantic Canada are separated by three and a half thousand kilometres of ocean. Yet for centuries, fishers, sailors, explorers, migrants, emigrants, merchants, messengers, messages, packets, ships, submarine cables, aeroplanes, satellite signals and wireless radio waves have attempted to bridge this distance. These comings and goings have left traces. Generations of transatlantic migrations have engendered networks of communications. As narratives of place and displacement travel across, beyond, and through these networks, they become informed by the networks’ structures and inflected with the syntax and grammar of the networks’ code languages. Writing coastlines interrogates this in-between space with a series of questions: When does leaving end and arriving begin? When does the emigrant become the immigrant? What happens between call and response? What narratives resonate in the spaces between places separated by time, distance, and ocean yet inextricably linked by generations of immigration? This thesis takes an overtly interdisciplinary approach to answering these questions. This practice-led research refers to and infers from the corpora and associated histories, institutions, theoretical frameworks, modes of production, venues, and audiences of the visual, media, performance, and literary arts, as well as from the traditionally more scientific realms of cartography, navigation, network archaeology, and creative computing. Writing Coastlines navigates the emerging and occasionally diverging theoretical terrains of electronic literature, locative narrative, media archaeology, and networked art through the methodology of performance writing pioneered at Dartington College of Art (Bergvall 1996, Hall 2008). Central to this methodology is an iterative approach to writing, which interrogates the performance of writing in and across contexts toward an extended compositional process. Writing Coastlines will contribute to a theoretical framework and methodology for the creation and dissemination of networked narrative structures for stories of place and displacement that resonate between sites, confusing and confounding boundaries between physical and digital, code and narrative, past and future, home and away. Writing Coastlines will contribute to the creation of a new narrative context from which to examine a multi-site-specific place-based identity by extending the performance writing methodology to incorporate digital literature and locative narrative practices, by producing and publicly presenting a significant body of creative and critical work, and by developing a mode of critical writing which intertwines practice with theory

Acoustic microbubble trapping in blood mimicking fluid

Microbubble (MB) volumetric pulsations can be selectively seeded with external ultrasonic fields. The therapeutic use of this phenomenon encompass mechanical thrombolysis and targeted drug deliveries through sonoporating endothelial cells. However, expected outcomes are still plagued by low bubble concentrations and short circulation time after administration. MBs preferentially flow along the centerline of large vessels which deteriorates biological targeting methodology in the case of vascular disease treatment with MBs. Simultaneous MB imaging and trapping against high flow rates has been recently proposed by instantaneously switching optimized ultrasonic beams. Principles were previously validated by circulating MBs with purified water through a flow phantom. But differences between blood and water call for preliminary investigations with blood mimicking fluid (BMF). This study demonstrated the capability of trapping bubbles in BMF with the acoustic trap but with nearly 40% efficiency reduction over the control in water, being present by the suppressed increase of image brightness

Increased Mixing and Turbulence in the Wake of Offshore Wind Farm Foundations

The addition of offshore wind farms (OWFs) to stratified regions of shelf seas poses an anthropogenic source of turbulence, in which the foundation structures remove power from the oceanic flow that is fed into turbulent mixing in the wake downstream. The loss of stratification within the wake of a single OWF structure is observed for the first time by means of field observations, which enable a qualitative characterization of the disturbed flow downstream. These results are complemented with high-resolution large eddy simulations of four different stratification strengths that allow for a quantification of turbulence and mixing quantities in the wake of a foundation structure. The turbulent wake of a structure is narrow and highly energetic within the first 100 m, with the dissipation of turbulent kinetic energy well above background levels downstream of the structure. A single monopile is responsible for 7–10% additional mixing to that of the bottom mixed layer, whereby ∼10% of the turbulent kinetic energy generated by the structure is used in mixing. Although the effect of a single turbine on stratification is relatively low, large-scale OWFs could significantly affect the vertical structure of a weakly stratified water column. Further, rough estimates show that the rate of formation of stratification in the study area is of the same order of magnitude as the additional mixing promoted by the structures, thus OWFs could modify the stratification regime and water column dynamics on a seasonal scale, depending on local conditions and farm geometries

Sufficient Covariate, Propensity Variable and Doubly Robust Estimation

Statistical causal inference from observational studies often requires adjustment for a possibly multi-dimensional variable, where dimension reduction is crucial. The propensity score, first introduced by Rosenbaum and Rubin, is a popular approach to such reduction. We address causal inference within Dawid's decision-theoretic framework, where it is essential to pay attention to sufficient covariates and their properties. We examine the role of a propensity variable in a normal linear model. We investigate both population-based and sample-based linear regressions, with adjustments for a multivariate covariate and for a propensity variable. In addition, we study the augmented inverse probability weighted estimator, involving a combination of a response model and a propensity model. In a linear regression with homoscedasticity, a propensity variable is proved to provide the same estimated causal effect as multivariate adjustment. An estimated propensity variable may, but need not, yield better precision than the true propensity variable. The augmented inverse probability weighted estimator is doubly robust and can improve precision if the propensity model is correctly specified

Reheating Temperature and Gauge Mediation Models of Supersymmetry Breaking

For supersymmetric theories with gravitino dark matter, the maximal reheating temperature consistent with big bang nucleosynthesis bounds arises when the physical gaugino masses are degenerate. We consider the cases of a stau or sneutrino next-to-lightest superpartner, which have relatively less constraint from big bang nucleosynthesis. The resulting parameter space is consistent with leptogenesis requirements, and can be reached in generalized gauge mediation models. Such models illustrate a class of theories that overcome the well-known tension between big bang nucleosynthesis and leptogenesis.Comment: 30 pages, 4 figures; v2: refs adde

Crossing of shears bands in 197Pb: B(M1) values and semiclassical description

Subpicosecond lifetimes of states in shears band 1 in 97Pb were measured by means of the recoil distance method employing Gammasphere and the New Yale Plunger Device. The extracted reduced matrix elements, B(M1), show a clear sensitivity to the crossing of different shears configurations reflecting the closing and reopening of the shears blades. The energies and B(M1) values in the band crossing region are successfully described in the framework of the semiclassical model of the shears bands. The relevance of core rotation contributions are shown. The results point to the existence of shears states with an angular momentum coupling angle larger than 90°

Dust detection by the wave instrument on STEREO: nanoparticles picked up by the solar wind?

The STEREO/WAVES instrument has detected a very large number of intense voltage pulses. We suggest that these events are produced by impact ionisation of nanoparticles striking the spacecraft at a velocity of the order of magnitude of the solar wind speed. Nanoparticles, which are half-way between micron-sized dust and atomic ions, have such a large charge-to-mass ratio that the electric field induced by the solar wind magnetic field accelerates them very efficiently. Since the voltage produced by dust impacts increases very fast with speed, such nanoparticles produce signals as high as do much larger grains of smaller speeds. The flux of 10-nm radius grains inferred in this way is compatible with the interplanetary dust flux model. The present results may represent the first detection of fast nanoparticles in interplanetary space near Earth orbit.Comment: In press in Solar Physics, 13 pages, 5 figure

Species-specific responses of planktivorous fish to the introduction of a new piscivore: implications for prey fitness

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75539/1/j.1365-2427.2007.01810.x.pd