Basement highs: definitions, characterisation and origins

A glossary of commonly used terms related to the geometric forms and geological settings of basement highs is presented to assist cross-disciplinary understanding, qualifying prefixes for the term basement are discussed and a scheme for characterising basement highs is presented. This scheme is designed to standardise, and to add rigour to, description of basement highs. It will thereby enhance basement high comparisons and assist understanding of basement highs across technical disciplines. The scheme enables systematic characterisation of: the geometry of a basement high; the lithologic units and structures in, above and around it; timings; tectonics and origins of the basement high and play elements relating to resource prospectivity. Use of this scheme is demonstrated using the southern Rona Ridge (West of Shetland, UK Continental Shelf). The tectonic, isostatic, erosional and stratigraphic processes that form basement highs are also discussed, and examples in proven petroleum systems are presented.publishedVersio

A framework for applying spatial decision support systems in land use planning.

Thesis (M.Sc.Sur.)-University of Natal, Durban, 2002.For local authorities to manage land policies effectively data bases of land use information that are current and mirror development on the ground are required. At present local authorities have no mechanisms in place to acquire maintain and spatially link land use information. Detailed land use information is not generally available at the local level. Generally little attention is paid to maintaining the expensive data which is assembled when planning schemes, development plans or projects are prepared. Land use planning has traditionally focussed on the control rather than the facilitation of development. Details of the actual land use on the ground are generally ignored as tariffs for tax purposes are set on the zoning of the land or a flat rate rather than the actual land use. This lack of land use information, which is exacerbated by informal settlement, causes delays in approving new land uses. There is generally no data available for informal areas and land use and tenure is subject to the informal rules that have evolved with such settlements. If these areas are to be included in the formal land management systems, ways of including and maintaining land use information about these settlements must be developed. By reviewing land information theory, the South African legal land development framework and using a small town as a case study, I have shown that provided certain conditions are met a Spatial Decision Support System (SDSS), designed to record and maintain the land use data necessary to support land use planning in both formal and informal contexts, could be a valuable land management tool. Such a system should be implemented in partnership with local communities and should; • support local level land use decision making and regulation • serve as a land management tool to integrate formal and informal communities • have mechanisms to keep land use information current • be transparent about the type of land use information • develop linkages with regional government to provide detailed land information over time

The role of library and information services in supporting learning

Healthcare LIS professionals have always supported students and those undertaking continuing professional development. Increasingly, they support statutory periodic refreshment and form collaborative partnerships with public and academic libraries. This chapter explores changes impacting on libraries as they evolve to accommodate emerging learning needs. It discusses problem-based learning, enquiry-based learning and 'clinical placements' before outlining a case study that typifies such changes. It concludes with the implications of these developments for the role of healthcare librarians

Aerodesign and validation of turning struts for an intermediate compressor duct

Compressor transition ducts, also referred to as S-shaped ducts, are used to connect the low- or intermediate-pressure compressor (LPC) with the high-pressure compressor (HPC) in 2- and 3-spool turbofan engine configurations respectively. This paper focuses on studies on a concept which aims to shorten the compressor module by introducing aerodynamically lifting/turning struts in the compressor transition duct. This concept is labeled fully turning, as the struts in the duct assume the complete aerodynamic function of the last row of stators of the LPC. Through CFD analysis and low-speed experimental evaluation, this concept is further developed with promising results. It is shown that there is potential to reduce the length of the compressor module by 25% of the duct length through elimination of the last stator row in the LPC, whilst providing comparable or improved aerodynamic performance compared to a conventional configuration. This paper presents a combined experimental and numerical study where a fully turning concept (without LPC OGV, having 45 deg turning in the duct) is compared back-to-back with a moderately turning concept (with an off-loaded LPC OGV and 20 deg turning in the duct). Numerical analysis of a conventional duct configuration (where the OGV remains, with symmetrical non-turning struts) is used as baseline

Natural Supergravity inflation

We identify a new mechanism in supergravity theories which leads to successful inflation without any need for fine tuning. The simplest model yields a spectrum of density fluctuations tilted away from scale-invariance and negligible gravitational waves. We demonstrate that this is consistent with the observed large-scale structure for a cold dark matter dominated, critical density universe. The model can be tested through measurements of microwave background anisotropy on small angular scales.Comment: 14 pages (revtex) including 3 figures (epsf); Minor changes to Introduction and discussion and modified Figure 1; to appear in Phys. Lett. B; Postscript also available from ftp://ftp.physics.ox.ac.uk/pub/local/users/sarkar/SugraInfl.ps.g

Limitations of model fitting methods for lensing shear estimation

Gravitational lensing shear has the potential to be the most powerful tool for constraining the nature of dark energy. However, accurate measurement of galaxy shear is crucial and has been shown to be non-trivial by the Shear TEsting Programme. Here we demonstrate a fundamental limit to the accuracy achievable by model-fitting techniques, if oversimplistic models are used. We show that even if galaxies have elliptical isophotes, model-fitting methods which assume elliptical isophotes can have significant biases if they use the wrong profile. We use noise-free simulations to show that on allowing sufficient flexibility in the profile the biases can be made negligible. This is no longer the case if elliptical isophote models are used to fit galaxies made up of a bulge plus a disk, if these two components have different ellipticities. The limiting accuracy is dependent on the galaxy shape but we find the most significant biases for simple spiral-like galaxies. The implications for a given cosmic shear survey will depend on the actual distribution of galaxy morphologies in the universe, taking into account the survey selection function and the point spread function. However our results suggest that the impact on cosmic shear results from current and near future surveys may be negligible. Meanwhile, these results should encourage the development of existing approaches which are less sensitive to morphology, as well as methods which use priors on galaxy shapes learnt from deep surveys.Comment: 10 pages, 8 figure

Experimental study of the unsteady aerodynamics the compressor-combustor interface of a lean burn combustion system

To meet the technological challenges of lean burn, low emission combustion knowledge based design methodologies must be developed. This paper presents back-to-back, time-averaged and time-resolved aerodynamic measurements made using a unique state-of-the-art fully annular isothermal test facility incorporating a 1/2 stage axial compressor and a typical lean burn, low emission combustor geometry and either a clean or a strutted OGV/pre-diffuser system. The various measurement techniques employed (miniature five-hole probe, hot-wire anemometry, PIV) show a good level of agreement highlighting both the effect of including pre-diffuser struts and the notable unsteadiness present in the OGV/pre-diffuser system. The data presented provide the first evidence of the highly unsteady nature of the flow issuing from a pre-diffuser and potentially influencing the downstream external combustor aerodynamics

Two 100 Mpc-scale structures in the 3-D distribution of radio galaxies and their implications

We present unequivocal evidence for a huge (~80 x 100 x 100 Mpc^3) super-structure at redshift z=0.27 in the 3-D distribution of radio galaxies from the TONS08 sample, confirming tentative evidence for such a structure from the 7C redshift survey (7CRS). A second, newly discovered super-structure is also less securely found at redshift 0.35 (of dimensions ~100 x 100 x 100 Mpc^3). We present full observational details on the TONS08 sample which was constructed to probe structures in the redshift range 0 < z < 0.5 by matching NVSS sources with objects in APM catalogues to obtain a sample of optically bright (E ~ R 3 mJy) radio galaxies in the same 25 deg^2 area as part-II of the 7CRS. Out of the total sample size of 84 radio galaxies, at least 25 are associated with the two ~100 Mpc-scale super-structures. We use quasi-linear structure formation theory to estimate the number of such structures expected in the TONS08 volume if the canonical value for radio galaxy bias is assumed. Under this assumption, the structures represent ~ 4-5 sigma peaks in the primordial density field and their expected number is low (~10^-2 - 10^-4). Fortunately, there are several plausible explanations (many of which are testable) for these low probabilities in the form of potential mechanisms for boosting the bias on large scales. These include: the association of radio galaxies with highly biased rich clusters in super-structures, enhanced triggering by group/group mergers, and enhanced triggering and/or redshift space distortion in collapsing systems as the growth of super-structures moves into the non-linear regime (abridged).Comment: Accepted for publication in MNRAS. 26 pages,16 figures. spectra can be found in: http://www-astro.physics.ox.ac.uk/~brand/08_paper.ps.g

Successful Use of a Cadaver Model to Teach Ultrasound-Guided Breast Procedures to Surgical Trainees

IntroductionIn academic breast surgery, ultrasound use tends to be limited to radiology departments, thus formal surgical resident training in breast ultrasound is sparse. Building on residents' ultrasound skills in our general surgery training program, we developed a novel curriculum to teach ultrasound-guided breast procedures (UGBPs), including core needle biopsy (CNB) and wire localization (WL). We hypothesized that learning UGBPs on cadavers would be preferred to learning with a breast phantom model using chicken breasts.MethodsResidents received a 1-h lecture on breast CNB and WL followed by a 1-h hands-on laboratory session. Olives stuffed with red pimentos were used to replicate breast masses and implanted in chicken breasts and the breasts of lightly embalmed and unembalmed female cadavers. All residents practiced UGBPs with a course instructor on both models. Residents completed anonymous prelaboratory and postlaboratory surveys utilizing five-point Likert scales.ResultsA total of 35 trainees participated in the didactics; all completed the prelaboratory survey and 28 completed the postlaboratory survey. Participant clinical year ranged from 1 to 6. Residents' confidence in describing and performing CNBs and WLs increased significantly on postlaboratory surveys, controlling for clinical year (P&nbsp;&lt;&nbsp;0.001). Eighty-point seven percent preferred learning UGBPs on cadavers over phantoms most commonly citing that the cadaver was more realistic.ConclusionsFollowing a novel 2-h UGBP training curriculum using phantom and cadaveric models, resident confidence in describing and performing UGBPs significantly improved. Most favored the cadaveric model and reported that the course prepared them for real-life procedures

Monitoring of biomarkers in heart failure.

The role of biomarkers is increasingly recognized in heart failure (HF) management, for diagnosis, prognostication, and screening of high-risk patients. Beyond natriuretic peptides and troponins, the utility of novel, emerging biomarkers is less established. This document reflects the key points of a Heart Failure Association of the European Society of Cardiology (ESC) consensus meeting on biomarker monitoring in HF