385 research outputs found
Theatre and performance design: a reader in scenography
This volume, the first of its kind in this field, brings together over fifty key texts and newly commissioned works that provide a critical and contextual framework for the analysis of theatre and performance design. The collection and analysis of material for the volume was undertaken with Andrew Nisbet, but Jane Collins was responsible for all of the additional writing, including the essays that frame each section. The volume was nominated for the TaPRA (Theatre and Performance Research Association) David Bradby Award for Research in International Theatre and Performance in 2011. Collins was invited to talk about the book at the opening of the Prague Quadrennial of Performance Design and Space in June 2011 and as guest speaker at the 15th Bharat Rang Mahotsav, International Theatre Festival in Delhi in January 2013. It has been reviewed in international journals including New Theatre Quarterly and Australasian Drama Studies.
Theatre and Performance Design: A Reader in Scenography is an essential resource for those interested in the visual composition of performance and related scenographic practices. Theatre and performance studies, cultural theory, fine art, philosophy and the social sciences are brought together in one volume to examine the principle forces that inform understanding of theatre and performance design. The volume is organised thematically in five sections: Looking, the experience of seeing; Space and place; The designer: the scenographic; Bodies in space; and, Making meaning. This major collection of key writings provides a much needed critical and contextual framework for the analysis of theatre and performance design. By locating this study within the broader field of scenography - the term increasingly used to describe a more integrated reading of performance - this unique anthology recognises the role played by all the elements of production in the creation of meaning. Edited and with an introduction by Jane Collins and Andrew Nesbit, contributors include Josef Svoboda, Richard Foreman, Roland Barthes, Oscar Schlemmer, Maurice Merleau-Ponty, Richard Schechner, Jonathan Crary, Elizabeth Wilson, Henri Lefebvre, Adolph Appia, and Herbert Blau
Interferometer testbed: Overview and hardware summary
Viewgraphs on an overview and hardware summary for an interferometer testbed are presented. Topics covered include: reference mission and science requirements; science requirements derivation; reference spacecraft design summary; testbed requirements and performance metric; disturbance source and signal; and testbed architecture
Can CT scan protocols used for radiotherapy treatment planning be adjusted to optimise image quality and patient dose? A systematic review
This article reviews publications related to the use of CT scans for radiotherapy treatment planning, specifically the impact of scan protocol changes on CT number and treatment planning dosimetry and on CT image quality. A search on PubMed and EMBASE and a subsequent review of references yielded 53 relevant articles. CT scan parameters significantly affect image quality. Some will also affect Hounsfield unit (HU) values, though this is not comprehensively reported on. Changes in tube kilovoltage and, on some scanners, field of view and reconstruction algorithms have been found to produce notable HU changes. The degree of HU change which can be tolerated without changing planning dose by >1% depends on the body region and size, planning algorithms, treatment beam energy and type of plan. A change in soft-tissue HU value has a greater impact than changes in HU for bone and air. The use of anthropomorphic phantoms is recommended when assessing HU changes. There is limited published work on CT scan protocol optimization in radiotherapy. Publications suggest that HU tolerances of ±20âHU for soft tissue and of ±50âHU for the lung and bone would restrict dose changes in the treatment plan to <1%. Literature related to the use of CT images in radiotherapy planning has been reviewed to establish the acceptable level of HU change and the impact on image quality of scan protocol adjustment. Conclusions have been presented and further work identified
Design of an optical interferometer spacecraft
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1992.Includes bibliographical references (leaves 131-134)by Andrew Marc Nisbet.M.S
A multi-centre analysis of radiotherapy beam output measurement
Background and Purpose Radiotherapy requires tight control of the delivered dose. This should include the variation in beam output as this may directly affect treatment outcomes. This work provides results from a multi-centre analysis of routine beam output measurements. Materials and Methods A request for 6MV beam output data was submitted to all radiotherapy centres in the UK, covering the period January 2015 â July 2015. An analysis of the received data was performed, grouping the data by manufacturer, machine age, and recording method to quantify any observed differences. Trends in beam output drift over time were assessed as well as inter-centre variability. Annual trends were calculated by linear extrapolation of the fitted data. Results Data was received from 204 treatment machines across 52 centres. Results were normally distributed with mean of 0.0% (percentage deviation from initial calibration) and a 0.8% standard deviation, with 98.1% of results within ±2%. There were eight centres relying solely on paper records. Annual trends varied greatly between machines with a mean drift of +0.9%/year with 95th percentiles of +5.1%/year and -2.2%/year. For the machines of known age 25% were over ten years old, however there was no significant differences observed with machine age. Conclusions Machine beam output measurements were largely within ±2% of 1.00cGy/MU. Clear trends in measured output over time were seen, with some machines having large drifts which would result in additional burden to maintain within acceptable tolerances. This work may act as a baseline for future comparison of beam output measurements.</p
Characterization of Inorganic Scintillator Detectors for Dosimetry in Image-Guided Small Animal Radiotherapy Platforms
The purpose of the study was to characterize a detection system based on inorganic scintillators and determine its suitability for dosimetry in preclinical radiation research. Dose rate, linearity, and repeatability of the response (among others) were assessed for medium-energy X-ray beam qualities. The response's variation with temperature and beam angle incidence was also evaluated. Absorbed dose quality-dependent calibration coefficients, based on a cross-calibration against air kerma secondary standard ionization chambers, were determined. Relative output factors (ROF) for small, collimated fields (â€10 mm Ă 10 mm) were measured and compared with Gafchromic film and to a CMOS imaging sensor. Independently of the beam quality, the scintillator signal repeatability was adequate and linear with dose. Compared with EBT3 films and CMOS, ROF was within 5% (except for smaller circular fields). We demonstrated that when the detector is cross-calibrated in the user's beam, it is a useful tool for dosimetry in medium-energy X-rays with small fields delivered by Image-Guided Small Animal Radiotherapy Platforms. It supports the development of procedures for independent "live" dose verification of complex preclinical radiotherapy plans with the possibility to insert the detectors in phantoms
Surface grafting of electrospun fibers using ATRP and RAFT for the control of biointerfacial interactions
BACKGROUND The ability to present signalling molecules within a low fouling 3D environment that mimics the extracellular matrix is an important goal for a range of biomedical applications, both in vitro and in vivo. Cell responses can be triggered by non-specific protein interactions occurring on the surface of a biomaterial, which is an undesirable process when studying specific receptor-ligand interactions. It is therefore useful to present specific ligands of interest to cell surface receptors in a 3D environment that minimizes non-specific interactions with biomolecules, such as proteins. METHOD In this study, surface-initiated atom transfer radical polymerization (SI-ATRP) of poly(ethylene glycol)-based monomers was carried out from the surface of electrospun fibers composed of a styrene/vinylbenzyl chloride copolymer. Surface initiated radical addition-fragmentation chain transfer (SI-RAFT) polymerisation was also carried out to generate bottle brush copolymer coatings consisting of poly(acrylic acid) and poly(acrylamide). These were grown from surface trithiocarbonate groups generated from the chloromethyl styrene moieties existing in the original synthesised polymer. XPS was used to characterise the surface composition of the fibers after grafting and after coupling with fluorine functional XPS labels. RESULTS Bottle brush type coatings were able to be produced by ATRP which consisted of poly(ethylene glycol) methacrylate and a terminal alkyne-functionalised monomer. The ATRP coatings showed reduced non-specific protein adsorption, as a result of effective PEG incorporation and pendant alkynes groups existing as part of the brushes allowed for further conjugation of via azide-alkyne Huisgen 1,3-dipolar cycloaddition. In the case of RAFT, carboxylic acid moieties were effectively coupled to an amine label via amide bond formation. In each case XPS analysis demonstrated that covalent immobilisation had effectively taken place. CONCLUSION Overall, the studies presented an effective platform for the preparation of 3D scaffolds which contain effective conjugation sites for attachment of specific bioactive signals of interest, as well as actively reducing non-specific protein interactions.This research was supported by the Cooperative Research Centre for
Polymers (CRCP)
Sea-Ice Distribution in the Bering and Chukchi Seas: Information from Historical Whaleshipsâ Logbooks and Journals
Satellite data have revealed dramatic losses of Northern Hemisphere sea ice since the end of the 1970s. To place these changes in a longer-term context, we draw on daily observations taken from logbooks and journals of whaling vessels cruising in the Bering and Chukchi seas to investigate sea-ice conditions in this region of the Arctic between 1850 and 1910. We compare these observations to sea-ice data from 1972 to 1982, which predate the majority of the recent changes and cover a period recognized as a relative maximum in recent Bering Sea ice extent. Records from May indicate that end-of-winter sea-ice extent in the Bering Sea during the mid 19th century closely resembled that in the 1972 â 82 data. However, the historical data reveal that sea ice was more extensive during summer, with the greatest difference occurring in July. This pattern indicates a later and more rapid seasonal retreat. These conclusions highlight the value of historical data, which we have far from exhausted in this study.Des donnĂ©es satellitaires rĂ©vĂšlent que lâhĂ©misphĂšre nord a enregistrĂ© des pertes dramatiques de glaces de mer depuis la fin des annĂ©es 1970. Afin de mettre ces changements dans un plus long contexte, nous nous appuyons sur les observations quotidiennes tirĂ©es de journaux et de carnets de bord de baleiniers ayant parcouru la mer de BĂ©ring et la mer des Tchouktches dans le but dâĂ©tudier les glaces de mer de cette rĂ©gion de lâArctique entre les annĂ©es 1850 et 1910. Nous comparons ces observations aux donnĂ©es sur les glaces de mer recueillies de 1972 Ă 1982 â soit avant que la plupart des rĂ©cents changements nâaient Ă©tĂ© enregistrĂ©s â ce qui couvre une pĂ©riode reconnue comme un maximum relatif en matiĂšre dâĂ©tendue rĂ©cente des glaces dans la mer de BĂ©ring. Les donnĂ©es enregistrĂ©es en mai laissent entrevoir que lâĂ©tendue des glaces de mer en fin dâhiver dans la mer de BĂ©ring au milieu du XIXe siĂšcle ressemblait beaucoup Ă lâĂ©tendue des glaces dont tĂ©moignent les donnĂ©es prĂ©levĂ©es entre 1972 et 1982. Cependant, les donnĂ©es historiques rĂ©vĂšlent que les glaces de mer Ă©taient plus considĂ©rables au cours de lâĂ©tĂ©, la plus grande diffĂ©rence se manifestant au mois de juillet. Cette tendance indique donc un retrait saisonnier plus tardif et plus rapide. Les conclusions mettent en Ă©vidence lâimportance des donnĂ©es historiques, que nous sommes loin dâavoir Ă©puisĂ©es dans le cadre de cette Ă©tude
Potential lethal damage repair in glioblastoma cells irradiated with ion beams of various types and levels of linear energy transfer
Glioblastoma (GBM), a Grade IV brain tumour, is a well-known radioresistant cancer. To investigate one of the causes of radioresistance, we studied the capacity for potential lethal damage repair (PLDR) of three altered strains of GBM: T98G, U87 and LN18, irradiated with various ions and various levels of linear energy transfer (LET). The GBM cells were exposed to 12C and 28Si ion beams with LETs of 55, 100 and 200 keV/ÎŒm, and with X-ray beams of 1.7 keV/ÎŒm. Mono-energetic 12C ions and 28Si ions were generated by the Heavy Ion Medical Accelerator at the National Institute of Radiological Science, Chiba, Japan. Clonogenic assays were used to determine cell inactivation. The ability of the cells to repair potential lethal damage was demonstrated by
allowing one identical set of irradiated cells to repair for 24 h before subplating. The results show there is definite
PLDR with X-rays, some evidence of PLDR at 55 keV/ÎŒm, and minimal PLDR at 100 keV/ÎŒm. There is no observable PLDR at 200 keV/ÎŒm. This is the first study, to the authorsâ knowledge, demonstrating the capability of GBM cells to repair potential lethal damage following charged ion irradiations. It is concluded that a GBMâs PLDR is dependent on LET, dose and GBM strain; and the more radioresistant the cell strain, the greater the PLDR
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