Desiring to bear the word : the poetry of Stevie Smith

This thesis argues that Stevie Smith's poetic style can be attributed to her gender. It shows that the dominant status of masculine poetry and poetics, and the prejudice against women poets, affected Smith's poetic style and led to her search for the source ofa feminine poetic voice. The prevailing circumstances when Smith began to publish poetry are examined in order to establish Smith's socially appropriate poetics. The thesis offers detailed textual analyses, informed by feminist theories. Chapters one and two take a socio-historic materialist approach to examine the problems confronting Smith as a woman poet. This includes considering Smith's categorisation as a poet of the suburbs, and the dominance of the Auden group. Chapters three to five look at Smith's use of children's literature and the influence of Blake and Wordsworth. Judith Butler's ideas ofperformativity, and Carolyn Steedman's of interiority, are used to propose that both are relevant to Smith's preoccupation with childhood. Smith's engagement with, and subversion of, the male poetic tradition and the idea of the muse are also considered. The last two chapters on the themes of birth and death draw on the ideas of Helene Cixous and Julia Kristeva in order to argue that Smith's longing for death is a wish for rebirth, therefore a return to the maternal semiotic source which facilitates poetry. In this way death does not withhold language, but enables linguistic acquisition. This thesis adds to existing knowledge about Smith, and extends debates surrounding women and poetry. It contributes to feminist analyses of fairy tales, the poetic tradition, and the idea of the muse, and expands psycholinguistic theory to propose the relevance of death as well as infancy, and to suggest that Smith's preoccupations with the source of feminine poetry anticipates some fundamental theories of the 'French' feminists

Spectroscopic test of Bose-Einstein statistics for photons

Using Bose-Einstein-statistics-forbidden two-photon excitation in atomic barium, we have limited the rate of statistics-violating transitions, as a fraction $\nu$ of an equivalent statistics-allowed transition rate, to $\nu<4.0\times10^{-11}$ at the 90% confidence level. This is an improvement of more than three orders of magnitude over the best previous result. Additionally, hyperfine-interaction enabling of the forbidden transition has been observed, to our knowledge, for the first time

Inspiratory muscle recruitment during swallow and a comparison across airway behaviors.

During swallow, a negative esophageal pressure is present that, along positive pressure from the tongue, which works to move the bolus through the pharynx into the esophagus. This negative esophageal pressure is thought to be produced via recruitment of chest wall inspiratory muscles (diaphragm and parasternal). This current study aimed to examine respiratory muscle recruitment across behaviors which have known inspiratory muscle activity (eupnea, augmented breath and cough) and compare to swallow. It was hypothesized that there would be no significant difference in amplitude and muscle recruitment over 75 ms between swallow and eupnea, but cough and augmented breath would be significantly larger. Electromyograms (EMG) from the costal diaphragm and parasternal muscles were recorded and analyzed in five freely breathing anesthetized cats. Muscle recruitment was examined by taking both the root mean square over the initial 75 ms (RMS75) of each behavior and the maximum amplitude of muscle activity for the total duration of the behavior. Results found that there was a significant difference for maximum amplitude of muscle activation across all behaviors for the parasternal and for augmented breath and cough for the diaphragm. Muscle recruitment of parasternal was significantly different from swallow for the behavior of eupnea. These results, along with a growing body of evidence, provide credence to the theory that inspiratory muscle activity is part of the swallow central pattern generator. This work could provide needed clinical information for the evaluation of dysphagia in at-risk patients

Dimpling process in cold roll metal forming by finite element modelling and experimental validation

The dimpling process is a novel cold-roll forming process that involves dimpling of a rolled flat strip prior to the roll forming operation. This is a process undertaken to enhance the material properties and subsequent products’ structural performance while maintaining a minimum strip thickness. In order to understand the complex and interrelated nonlinear changes in contact, geometry and material properties that occur in the process, it is necessary to accurately simulate the process and validate through physical tests. In this paper, 3D non-linear finite element analysis was employed to simulate the dimpling process and mechanical testing of the subsequent dimpled sheets, in which the dimple geometry and material properties data were directly transferred from the dimpling process. Physical measurements, tensile and bending tests on dimpled sheet steel were conducted to evaluate the simulation results. Simulation of the dimpling process identified the amount of non-uniform plastic strain introduced and the manner in which this was distributed through the sheet. The plastic strain resulted in strain hardening which could correlate to the increase in the strength of the dimpled steel when compared to plain steel originating from the same coil material. A parametric study revealed that the amount of plastic strain depends upon on the process parameters such as friction and overlapping gap between the two forming rolls. The results derived from simulations of the tensile and bending tests were in good agreement with the experimental ones. The validation indicates that the finite element analysis was able to successfully simulate the dimpling process and mechanical properties of the subsequent dimpled steel products

Rings and Jets around PSR J2021+3651: the `Dragonfly Nebula'

We describe recent Chandra ACIS observations of the Vela-like pulsar PSR J2021+3651 and its pulsar wind nebula (PWN). This `Dragonfly Nebula' displays an axisymmetric morphology, with bright inner jets, a double-ridged inner nebula, and a ~30" polar jet. The PWN is embedded in faint diffuse emission: a bow shock-like structure with standoff ~1' brackets the pulsar to the east and emission trails off westward for 3-4'. Thermal (kT=0.16 +/-0.02 keV) and power law emission are detected from the pulsar. The nebular X-rays show spectral steepening from Gamma=1.5 in the equatorial torus to Gamma=1.9 in the outer nebula, suggesting synchrotron burn-off. A fit to the `Dragonfly' structure suggests a large (86 +/-1 degree) inclination with a double equatorial torus. Vela is currently the only other PWN showing such double structure. The >12 kpc distance implied by the pulsar dispersion measure is not supported by the X-ray data; spectral, scale and efficiency arguments suggest a more modest 3-4 kpc.Comment: 22 pages, 5 figures, 3 tables, Accepted to Ap

Design of New Cold Rolled Purlins by Experimental Testing and Direct Strength Method

New cold roll formed channel and zed sections for purlins, namely UltraBEAMTM2 and UltraZEDTM2, have been developed by Hadley Industries plc using a combined approach of experimental testing, finite element modelling and optimisation techniques. The new sections have improved strength to weight ratio by increasing the section’s strength by using stiffeners in the section webs. The European standards, Eurocode 3, use a traditional Effective Width Method to determine the strength of a cold formed steel member. However, the design of the new sections UltraBEAMTM2 and UltraZEDTM2 using this method is very complicated in calculating the effective section properties as these sections contain complex folded-in stiffeners. In addition, the incorporation of competing buckling modes such as distortional buckling can be difficult to analyse. To overcome difficulties of using Eurocode 3 or such a standard with the Effective Width Method for the design of these sections, the Direct Strength Method (DSM) is adopted for determining the section strengths. Four-point beam bending tests were carried out to determine the buckling and ultimate bending capacity of the UltraBEAMTM2 and UltraZEDTM2 sections. Results of experimental testing and Finite Element Analysis were initially used as validation for the design using the DSM. The DSM results in terms of in bending moment capacities were then compared with the experimental test results for a broader data in which the UltraBEAMTM2 and UltraZEDTM2 sections had a range of different width-to-thickness ratios. It showed an excellent agreement between test and DSM design values. It is concluded that the DSM is a powerful tool for the design and optimisation of the new cold roll formed channel and zed purlins

The role of DNA methylation in human pancreatic neuroendocrine tumours

Pancreatic neuroendocrine tumours (PNETs) are the second most common pancreatic tumour. However, relatively little is known about their tumourigenic drivers, other than mutations involving the multiple endocrine neoplasia 1 (MEN1), ATRX chromatin remodeler, and death domain-associated protein genes, which are found in ~40% of sporadic PNETs. PNETs have a low mutational burden, thereby suggesting that other factors likely contribute to their development, including epigenetic regulators. One such epigenetic process, DNA methylation, silences gene transcription via 5’methylcytosine (5mC), and this is usually facilitated by DNA methyltransferase enzymes at CpG-rich areas around gene promoters. However, 5’hydroxymethylcytosine, which is the first epigenetic mark during cytosine demethylation, and opposes the function of 5mC, is associated with gene transcription, although the significance of this remains unknown, as it is indistinguishable from 5mC when conventional bisulfite conversion techniques are solely used. Advances in array-based technologies have facilitated the investigation of PNET methylomes and enabled PNETs to be clustered by methylome signatures, which has assisted in prognosis and discovery of new aberrantly regulated genes contributing to tumourigenesis. This review will discuss the biology of DNA methylation, its role in PNET development, and impact on prognostication and discovery of epigenome-targeted therapies

Finite Element Analysis of Cold-Formed Dimpled Steel Columns

Dimpled steel products are produced from the combination of an innovative dimpling process and a traditional forming process such as cold-roll forming or press-braking. The wider use of cold-formed dimpled steel members has promoted considerable interest in the local instability and strength of these members. Of particular interest is their buckling behaviour and ultimate strength capacity. However, the dimpling process produces cold-formed sections with a complex ‘dimpled’ surface topography and the ‘dimpled’ material is nonuniformly work hardened through the entire thickness. Owing to these complex issues, there are no existing methods to calculate the buckling strength of the dimpled products and validate against physical measurements. This paper presents a Finite Element analysis of the compressive behaviour of cold-formed dimpled steel columns. True stress-strain data obtained from physical tests were incorporated into nonlinear simulations of dimpled steel columns. The simulation results were compared with compression test results on dimpled channel and lipped channel columns and good agreements in both buckling and ultimate strength were obtained. It is demonstrated that the Finite Element analysis can therefore be used to analyse and design cold-formed dimpled steel columns

Multibreather and vortex breather stability in Klein--Gordon lattices: Equivalence between two different approaches

In this work, we revisit the question of stability of multibreather configurations, i.e., discrete breathers with multiple excited sites at the anti-continuum limit of uncoupled oscillators. We present two methods that yield quantitative predictions about the Floquet multipliers of the linear stability analysis around such exponentially localized in space, time-periodic orbits, based on the Aubry band method and the MacKay effective Hamiltonian method and prove that their conclusions are equivalent. Subsequently, we showcase the usefulness of the methods by a series of case examples including one-dimensional multi-breathers, and two-dimensional vortex breathers in the case of a lattice of linearly coupled oscillators with the Morse potential and in that of the discrete $\phi^4$ model