Operational modes for a wave injection facility aboard spacelab and a sub-satellite

Various modes of operation are described for an orbiting wave injection facility planned to measure the properties of waves propagating in space plasma. Such a facility would cover a wide frequency range including MF and HF. Phase shift and Doppler shift measurements will yield more accurate measurements of echo time delay and the angle of arrival. Because Spacelab will involve some sub-satellites, some consideration is given to propagation between two vehicles both at HF and VHF

Traces of identity: the construction of white ethnicity in New Zealand.

Settler colonies arose out of a form of European colonialism where a white collectivity was installed permanently on territory formerly occupied by non-European 'indigenous' peoples. In British colonies where white settlers formed the majority population - the United States, Canada, Australia and New Zealand - the political, economic and cultural infrastructure has historically privileged whites over 'indigenous' groups. -In recent years territorial appropriations, which formed the basis of national wealth in these places, have been the focus of struggles for self-determination by 'first peoples'. This thesis focuses on the colonisation of New Zealand to show that although there were commonalities between white settler colonies, generally the historic specificity of nation building in each place, together with the way in which racial hierarchies were interpreted by colonialists, meant that national formations developed differently. New Zealand was the last of the 'dominions' to be settled and it became a commonplace that this was the most successful British colony in terms of racial harmony, largely because of a treaty made with the Maori. However recent reinterpretations of the nation's history have shown that while this treaty has functioned as a symbol of nationhood, notions of 'civility' which were brought to bear on the Maori people meant the terms of the treaty were never honoured. The thesis examines, through analyses of a variety of cultural artefacts, - from nineteenth century travel writing to contemporary cultural forms - films, television and museums -, the way ‘civilising discourses' underpinned a matrix of ethnic, gendered and class-based differences which legitimated the privilege of the settler majority. In recent years reinterpretations of the Treaty of Waitangi, and the severing of ties with Britain, have led to new forms of nationhood constructed around the ‘indigenisation' of the 'treaty partners' - Maori and Pakeha. Drawing on Cultural Studies approaches to representation and ethnicity, the thesis addresses issues which arise specifically from the way in which these shifts have challenged the hegemony of 'whiteness' in the colonial context

Alterations in thoracolumbosacral movement when pain causing lameness has been improved by diagnostic analgesia

Lameness, thoracolumbosacral pain and reduced range of motion (ROM) often coexist; better understanding of their relationship is needed. The objectives were to determine if thoracolumbosacral movement of horses changes when pain causing lameness is improved by diagnostic analgesia. We hypothesised that reduction of lameness will increase ROM of the thoracolumbosacral region. Thirteen horses with different types of hind limb lameness were trotted in straight lines and lunged on a 10 m diameter circle on left and right reins before and after lameness was subjectively substantially improved by diagnostic analgesia. Inertial sensor data were collected from the withers, thirteenth (T13) and eighteenth thoracic (T18) vertebrae, third lumbar (13) vertebra, tubera sacrale (TS), left and right tubera coxae. ROM of flexion-extension, axial rotation, lateral bending, dorsoventral, lateral-lateral motion and vertical movement symmetry were quantified at each thoracolumbar site. Hiphike difference (HHD), maximum difference (MaxDiff) and minimum difference (MinDiff) for the pelvic sensors were measured. Percentage changes for before and after diagnostic analgesia were calculated; mean standard deviation (SD) or median [interquartile range] were determined. Associations between the change in pelvic versus thoracolumbar movement symmetry after each local analgesic technique were tested. After resolution of lameness, HHD decreased by 7% [68%] (P = 0.006). The MinDiff decreased significantly by 33%[61%] (P = 0.01), 45 +/- 13% (P = 0.005) and 52 +/- 23% (P = 0.04), for TS, L3 and T18, respectively. There was significantly increased ROM in flexion-extension at T13, in axial rotation at T13, T18, 13 and in lateral-lateral ROM at 13. Thoracolumbosacral asymmetry and reduced ROM associated with lameness were both altered immediately by improvement in lameness using diagnostic analgesia. (C) 2017 Elsevier Ltd. All rights reserved

A Framework for the Landscape

It seems likely that string theory has a landscape of vacua that includes very many metastable de Sitter spaces. However, as emphasized by Banks, Dine and Gorbatov, no current framework exists for examining these metastable vacua in string theory. In this paper we attempt to correct this situation by introducing an eternally inflating background in which the entire collection of accelerating cosmologies is present as intermediate states. The background is a classical solution which consists of a bubble of zero cosmological constant inside de Sitter space, separated by a domain wall. At early and late times the flat space region becomes infinitely big, so an S-matrix can be defined. Quantum mechanically, the system can tunnel to an intermediate state which is pure de Sitter space. We present evidence that a string theory S-matrix makes sense in this background and contains metastable de Sitter space as an intermediate state.Comment: 29+13 pages, 25 figures; v2: minor corrections, references adde

Macroscopic limits of individual-based models for motile cell populations with volume exclusion

Partial differential equation models are ubiquitous in studies of motile cell populations, giving a phenomenological description of events which can be analyzed and simulated using a wide range of existing tools. However, these models are seldom derived from individual cell behaviors and so it is difficult to accurately include biological hypotheses on this spatial scale. Moreover, studies which do attempt to link individual- and population-level behavior generally employ lattice-based frameworks in which the artifacts of lattice choice at the population level are unclear. In this work we derive limiting population-level descriptions of a motile cell population from an off-lattice, individual-based model (IBM) and investigate the effects of volume exclusion on the population-level dynamics. While motility with excluded volume in on-lattice IBMs can be accurately described by Fickian diffusion, we demonstrate that this is not the case off lattice. We show that the balance between two key parameters in the IBM (the distance moved in one step and the radius of an individual) determines whether volume exclusion results in enhanced or slowed diffusion. The magnitude of this effect is shown to increase with the number of cells and the rate of their movement. The method we describe is extendable to higher-dimensional and more complex systems and thereby provides a framework for deriving biologically realistic, continuum descriptions of motile populations

Critical realism, agency and sickle cell: case studies of young people with sickle cell disorder at school

Critical realism suggests that historical structures may operate as underlying generative mechanisms but not always be activated. This explains the near-absence of references to racism by black students with sickle cell disorder (SCD). Through case studies we show how latent mechanisms are not activated, and how social actors come to develop corporate agency. Themes discussed include: wider/historical racisms (carers' own experiences of overt racism at school); conscious actions (moving away from a school where racism was experienced); naming racism as an emergent strategy (when communal discussions enable multiple negative experiences to be framed and named as racism); and `passing` (not ostensibly experiencing racism if one is sufficiently light-skinned). Critical realism suggests how racism may be structuring the experiences of students with SCD at school even in the absence of specific accounts by young people

Asymptotic Level Spacing of the Laguerre Ensemble: A Coulomb Fluid Approach

We determine the asymptotic level spacing distribution for the Laguerre Ensemble in a single scaled interval, $(0,s)$, containing no levels, E_{\bt}(0,s), via Dyson's Coulomb Fluid approach. For the $\alpha=0$ Unitary-Laguerre Ensemble, we recover the exact spacing distribution found by both Edelman and Forrester, while for $\alpha\neq 0$, the leading terms of $E_{2}(0,s)$, found by Tracy and Widom, are reproduced without the use of the Bessel kernel and the associated Painlev\'e transcendent. In the same approximation, the next leading term, due to a ``finite temperature'' perturbation (\bt\neq 2), is found.Comment: 10pp, LaTe

Lattice gluodynamics at negative g^2

We consider Wilson's SU(N) lattice gauge theory (without fermions) at negative values of beta= 2N/g^2 and for N=2 or 3. We show that in the limit beta -> -infinity, the path integral is dominated by configurations where links variables are set to a nontrivial element of the center on selected non intersecting lines. For N=2, these configurations can be characterized by a unique gauge invariant set of variables, while for N=3 a multiplicity growing with the volume as the number of configurations of an Ising model is observed. In general, there is a discontinuity in the average plaquette when g^2 changes its sign which prevents us from having a convergent series in g^2 for this quantity. For N=2, a change of variables relates the gauge invariant observables at positive and negative values of beta. For N=3, we derive an identity relating the observables at beta with those at beta rotated by +- 2pi/3 in the complex plane and show numerical evidence for a Ising like first order phase transition near beta=-22. We discuss the possibility of having lines of first order phase transitions ending at a second order phase transition in an extended bare parameter space.Comment: 7 pages, 7 figures, uses revtex, Eqs. 15-17 corrected, minor change