Value of using liver FDG uptake as background activity in standardizing FDG PET/CT studies

Thesis (M.A.)--Boston UniversityThe standardized uptake value (SUV) is increasingly being used for diagnosis, staging, and monitoring disease in clinical oncology. Comparing tumor SUV to background SUV is an attractive way to minimize variability and ensure the quality of scans across different institutions. The liver has been identified as a potential source for background normalization, however no studies have compared the liver to other background sites for a variety of cancers. The purpose of this study was to evaluate the use of liver uptake for the standardization of FDG PET/CT imaging. Scans from 145 patients were prospectively reviewed under the supervision of a radiologist with board certification in nuclear medicine (R.M.S. , 3 years of experience). Liver SUV values were correlated to mediastinum SUV values in lung and breast cancer patients, and internal jugular vein (IJV) SUV values in head and neck cancer patients. The independent t-test was used to determine if there was a statistically significant affect of the amount of incubation time or use of intravenous contrast on the SUV. For the lung and breast cancer patients, a strong correlation was observed between the mediastinum SUVmean and liver SUVmean (r = 0.89), whereas for the head and neck cancer patients, a weaker correlation was observed between the IJV SUVmean and the liver SUVmean (r = 0.69). Neither the amount of incubation time nor the use of IV contrast demonstrated a significant affect on the SUV. We conclude that liver SUVmean may be used to standardize FOG PET/CT studies in cancers of the lung, breast and head and neck. However, additional studies in other cancers as well as the affects of age, gender, benign disease and use of chemotherapy are still desired before widespread adoption of this standard

Conformity, deformity and reformity

In any given field of artistic practice, practitioners position themselves—or find themselves positioned—according to interests and allegiances with specific movements, genres, and traditions. Selecting particular frameworks through which to approach the development of new ideas, patterns and expressions, balance is invariably maintained between the desire to contribute towards and connect with a particular set of domain conventions, whilst at the same time developing distinction and recognition as a creative individual. Creativity through the constraints of artistic domain, discipline and style provides a basis for consideration of notions of originality in the context of activity primarily associated with reconfiguration, manipulation and reorganisation of existing elements and ideas. Drawing from postmodern and post-structuralist perspectives in the analysis of modern hybrid art forms and the emergence of virtual creative environments, the transition from traditional artistic practice and notions of craft and creation, to creative spaces in which elements are manipulated, mutated, combined and distorted with often frivolous or subversive intent are considered. This paper presents an educational and musically focused perspective of the relationship between the individual and domain-based creative practice. Drawing primarily from musical and audio-visual examples with particular interest in creative disruption of pre-existing elements, creative strategies of appropriation and recycling are explored in the context of music composition and production. Conclusions focus on the interpretation of creativity as essentially a process of recombination and manipulation and highlight how the relationship between artist and field of practice creates unique creative spaces through which new ideas emerge

The business of invention: considering project management in the arts and industry

Project management has well developed theoretical constructs and is becom- ing increasingly well established in core strategy beyond the industrial and corporate sec- tors from which it first emerged. With a concurrent increase in the significance of innova- tion, project managing for creativity is an area of research and enquiry of considerable sig- nificance. Notionally occupying polar opposite cultural positions in terms of perspectives and processes of creativity, project management in the arts is widely considered to vary significantly from corporate strategy and process. If business were to be more generally characterised by ‘organisation’ and discipline, the arts are more commonly celebrated for disorganisation, indiscipline, and the fundamental challenge to organisation itself. Consid- ering both the confluences and variations between established project management theory in business and practice in the arts, this text introduces theoretical constructs pertaining to creative processes and highlights areas for consideration in the understanding and further development of project management theory

Creativity and authenticity: perspectives of creative value, utility and quality

This paper is written from the perspective of creative practitioners in sound, music and the visual arts teaching in UK higher education. Primarily concerned with the understanding of creativity as a developmental capacity and identifiable and measurable process and outcome, what began initially as a focused discussion about the assessment of creative artefacts developed progressively into a more general analysis of creative value in terms of reception and developmental experience. Recognising the impact of new technologies and the changing conceptions of creative technique and craft, collaboration and origination, and diversification of attendant interpretive meanings inherent with new artistic forms, the study is an attempt to establish a position from which pedagogic practices can be honed and refined to meet the expectations and needs of contemporary practitioners and educational contexts. The objective in any educational experience and any process of artistic creation being to enrich and to effectively inform further development steps, value is therefore a highly diverse and granular commodity, measurable on many different scales, and capable of understanding in many different ways. This is a study of considerations and perspectives and ways of understanding and working with creative value and an attempt to develop a framework through which to base creative decisions as educators and practitioners. Creativity models tend to emphasise utility and originality as the key factors in determining creative value; the wider recognition and impact of the outcomes of creative endeavour preeminent in the interpretation and attribution of quality and significance. Whilst most evident and analytically objectifiable in the study of reception and in the analysis of outcomes, creative practices and processes nevertheless feature more prominently in the interpretation of value in some fields. Whilst the products of the creative practice of artists, musicians and writers retain the centre ground in the discourse of creativity, the authentication of creative endeavour is nevertheless closely connected to the narratives surrounding the inception and development of the work and the security of the connection established between the creative object and the creative originator; the intangible and entirely conceptual matter of attribution and provenance often proving more significant than physical artefact in substantiating at least commercial value in many cases. Investigating the potential for a meaningful definition of ‘authentic creativity’, notions of novelty, ignorance, forgery, fakery, reproduction and patterning, provide a basis for consideration of creativity both as an unstable concept and in parallel as a metaphor for the human condition. Considering the discourse of authenticity and aesthetics, this paper explores different perspectives of creativity as lived experience and positions analysis in the narratives of insight, imagination, and the romanticism of discovery and talent. Introducing an analysis of creativity through a series of conceptual models to illustrate key concepts and ideas, this essay presents a discussion rooted in a context of collapsing distinctions between the natural and the artificial, the authentic and the inauthentic, the original and the copy, and develops a tentative definition of authentic creativity and creative authenticity for wider consideration. That creativity matters in education and society is widely acknowledged and appreciated. This paper argues for a greater focus on the lived experience of creativity and the significance of determining value in terms of human experience over productivity

The mechanics of Arabidopsis seed germination

Germination is defined as the protrusion of the embryonic radicle through the seed coat layers (endosperm and testa). As the radicle elongates, the testa ruptures, followed by rupture of the endosperm. Arabidopsis seeds exhibit a two-step germination process with sequential rupture of the testa and endosperm. We are interested in exploring the physical process of germination. Whilst much effort has previously been placed on genetic networks, a mathematical approach for furthering the understanding of the physical/mechanical properties of germination has not yet been described. The Mathematics in Plant Sciences Study Group helped us to develop a better understanding of the problem. Several different mathematical models were generated for radicle growth and endosperm stretching. These models were developed on multiscale dimensions – looking at the organ, tissue and cellular levels. The outcomes of the study group have heightened our interest in the mechanical aspects of germination, and we are currently progressing with a grant proposal – a collaboration between the Schools of Biosciences and Engineering at the University of Nottingham, and a group from the Department of Biology at the University of Freiburg, Germany

Cosmology with dropout selection: Straw-man surveys and CMB lensing

We seek to prove the means, motive and opportunity of 2 < z < 5 dropout galaxies for large-scale structure. Together with low-z tracers, these samples would map practically every linear mode and facilitate a tomographic decomposition of the CMB lensing kernel over an unprecedented volume, thereby yielding a proxy for (the time evolution of) matter density fluctuations that provides compelling tests of horizon-scale General Relativity, neutrino masses and Inflation-- viz., curvature, running of the spectral index and a scale-dependent halo bias induced by (local) primordial non-Gaussianity. Focusing on color-color selection, we estimate the completeness, contamination, and spectroscopic survey speed of tailored Lyman-break galaxy (LBG) samples. We forecast the potential of CMB lensing cross-correlation, clustering redshifts and Redshift-Space Distortions (RSD) analyses. In particular, we estimate: the depth dependence of interlopers based on CFHTLS data and propagate this to biases in cosmology; new inferences of (non-linear) halo bias at these redshifts and depths using legacy data; detailed forecasts of LBG spectra as would be observed by DESI, PFS, and their successors. We further assess the relative competitiveness of potential spectroscopic facilities based on an intuitive figure-of-merit and define a modernisation of traditional selections to the photometric system of LSST where necessary. We confirm these science cases to be compelling for achievable facilities in the next decade by defining a LBG sample of increasing Lyman-alpha equivalent width with redshift, which delivers both percent-level RSD constraints on the growth rate at high-z and measurements of CMB lensing cross-correlation at z=3 and 4 with a significance measured in the hundreds. Finally, we discuss the limitations and avenues for improvement beyond this initial exploration (abridged).Comment: 59 pages, comments welcom

A bayesian analysis of beta testing

In this article, we define a model for fault detection during the beta testing phase of a software design project. Given sampled data, we illustrate how to estimate the failure rate and the number of faults in the software using Bayesian statistical methods with various different prior distributions. Secondly, given a suitable cost function, we also show how to optimise the duration of a further test period for each one of the prior distribution structures considered

The supersingular locus of the Shimura variety for GU(1,n-1) over a ramified prime

We analyze the geometry of the supersingular locus of the reduction modulo p of a Shimura variety associated to a unitary similitude group GU(1,n-1) over Q, in the case that p is ramified. We define a stratification of this locus and show that its incidence complex is closely related to a certain Bruhat-Tits simplicial complex. Each stratum is isomorphic to a Deligne-Lusztig variety associated to some symplectic group over F_p and some Coxeter element. The closure of each stratum is a normal projective variety with at most isolated singularities. The results are analogous to those of Vollaard/Wedhorn in the case when p is inert.Comment: A few more corrections, to appear in Math. Zeitschrif