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2006

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Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme, Eli S. Saber, Wencheng Wu, Kartheek Chandu Dec 2006

Automated Algorithm For The Identification Of Artifacts In Mottled And Noisy Images, Onome Augustine Ugbeme, Eli S. Saber, Wencheng Wu, Kartheek Chandu

Articles

We describe a method for automatically classifying image-quality defects on printed documents. The proposed approach accepts a scanned image where the defect has been localized a priori and performs several appropriate image processing steps to reveal the region of interest. A mask is then created from the exposed region to identify bright outliers. Morphological reconstruction techniques are then applied to emphasize relevant local attributes. The classification of the defects is accomplished via a customized tree classifier that utilizes size or shape attributes at corresponding nodes to yield appropriate binary decisions. Applications of this process include automated/assisted diagnosis and repair ...


The Complexity Of Computing The Size Of An Interval, Lane A. Hemaspaandra, Christopher M. Homan, Sven Kosub, Klaus W. Wagner Dec 2006

The Complexity Of Computing The Size Of An Interval, Lane A. Hemaspaandra, Christopher M. Homan, Sven Kosub, Klaus W. Wagner

Articles

Given a p-order A over a universe of strings (i.e., a transitive, reflexive, antisymmetric relation such that if (x, y) ∈ A then |x| is polynomially bounded by |y|), an interval size function of A returns, for each string x in the universe, the number of strings in the interval between strings b(x) and t(x) (with respect to A), where b(x) and t(x) are functions that are polynomial-time computable in the length of x. By choosing sets of interval size functions based on feasibility requirements for their underlying p-orders, we obtain new characterizations of complexity classes ...


Xmm-Newton Detection Of X-Ray Emission From The Compact Steep Spectrum Radio Galaxy 3c303.1, Christopher P. O'Dea, Bu Mu, Diana M. Worral, Joel Kastner, Stefi A. Baum, Willem H. De Vries Dec 2006

Xmm-Newton Detection Of X-Ray Emission From The Compact Steep Spectrum Radio Galaxy 3c303.1, Christopher P. O'Dea, Bu Mu, Diana M. Worral, Joel Kastner, Stefi A. Baum, Willem H. De Vries

Articles

Using XMM we detect faint unresolved X-ray emission from the Compact Steep Spectrum radio galaxy 3C 303.1. We detect a thermal component at kT ≃ 0.8 keV which seems likely to be produced in the ISM of the host galaxy. There is evidence for a second component in the spectrum whose nature is currently ambiguous. Plausible hypotheses for the second component include (1) hot gas shocked by the expansion of the radio source, and (2) Synchrotron self- Compton emission from the southern radio lobe if the magnetic field is below the equipartition value by a factor of ∼ 3.5.


Cosmological Constraints From The Sdss Luminous Red Galaxies, Max Tegmark, Daniel J. Eisenstein, Michael Strauss, David H. Weinberg, Michael R. Blanton, Joshua A. Frieman, Masataka Fukugita, James E. Gunn, Andrew J. S. Hamilton, Gillian R. Knapp, Robert C. Nichol, Jeremiah P. Ostriker, Nikhil Padmanabhan, Will J. Percival, David J. Schlegel, Donald P. Schneider, Roman Scoccimarro, Uroš Seljak, Hee-Jong Seo, Molly Swanson, Alexander S. Szalay, Michael S. Vogeley, Jaiyul Yoo, Idit Zehavi, Kevork Abazajian, Scott F. Anderson, James Annis, Neta A. Bahcall, Bruce Bassett, Andreas Berlind, John Brinkman, Tamás Budavari, Francisco Castander, Andrew Connolly, Istvan Csabai, Mamoru Doi, Douglas P. Finkbeiner, Bruce Gillespie, Karl Glazebrook, Gregory S. Hennessy, David W. Hogg, Željko Ivezić, Bhuvnesh Jain, David Johnston, Stephen Kent, Donald Q. Lamb, Brian C. Lee, Huan Lin, Jon Loveday, Robert H. Lupton, Jeffrey A. Munn, Kaike Pan, Changbom Park, John Peoples, Jeffrey R. Pier, Adrian Pope, Michael Richmond, Constance Rockosi, Ryan Scranton, Ravi K. Sheth, Albert Stebbins, Christopher Stoughton, István Szapudi, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York Dec 2006

Cosmological Constraints From The Sdss Luminous Red Galaxies, Max Tegmark, Daniel J. Eisenstein, Michael Strauss, David H. Weinberg, Michael R. Blanton, Joshua A. Frieman, Masataka Fukugita, James E. Gunn, Andrew J. S. Hamilton, Gillian R. Knapp, Robert C. Nichol, Jeremiah P. Ostriker, Nikhil Padmanabhan, Will J. Percival, David J. Schlegel, Donald P. Schneider, Roman Scoccimarro, Uroš Seljak, Hee-Jong Seo, Molly Swanson, Alexander S. Szalay, Michael S. Vogeley, Jaiyul Yoo, Idit Zehavi, Kevork Abazajian, Scott F. Anderson, James Annis, Neta A. Bahcall, Bruce Bassett, Andreas Berlind, John Brinkman, Tamás Budavari, Francisco Castander, Andrew Connolly, Istvan Csabai, Mamoru Doi, Douglas P. Finkbeiner, Bruce Gillespie, Karl Glazebrook, Gregory S. Hennessy, David W. Hogg, Željko Ivezić, Bhuvnesh Jain, David Johnston, Stephen Kent, Donald Q. Lamb, Brian C. Lee, Huan Lin, Jon Loveday, Robert H. Lupton, Jeffrey A. Munn, Kaike Pan, Changbom Park, John Peoples, Jeffrey R. Pier, Adrian Pope, Michael Richmond, Constance Rockosi, Ryan Scranton, Ravi K. Sheth, Albert Stebbins, Christopher Stoughton, István Szapudi, Douglas L. Tucker, Daniel E. Vanden Berk, Brian Yanny, Donald G. York

Articles

We measure the large-scale real-space power spectrum P(k) using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from the Wilkinson Microwave Anisotropy Probe (WMAP). We employ a matrix-based power spectrum estimation method using Pseudo-Karhunen-Lo`eve eigenmodes, producing uncorrelated minimum-variance measurements in 20 k-bands of both the clustering power and its anisotropy due to redshift-space distortions, with narrow and well-behaved window functions in the range 0.01 h/Mpc < k < 0.2 h/Mpc. Results from the LRG and main galaxy samples are consistent, with the former providing higher signal-to-noise. Our results are robust to omitting angular and radial density fluctuations and are consistent between different parts of the sky. They provide a striking confirmation of the predicted large-scale CDM power spectrum. Combining only SDSS LRG and WMAP data places robust constraints on many cosmological parameters that complement prior analyses of multiple data sets. The LRGs provide independent cross-checks on m and the baryon fraction in good agreement with WMAP. Within the context of flat CDM models, our LRG measurements complementWMAP by sharpening the constraints on the matter density, the neutrino density and the tensor amplitude by about a factor of two, giving m = 0.24±0.02 (1 ), Pmν < 0.9 eV (95%) and r < 0.3 (95%). Baryon oscillations are clearly detected and provide a robust measurement of the comoving distance to the median survey redshift z = 0.35 independent of curvature and dark energy properties. Within the CDM framework, our power spectrum measurement improves the evidence for spatial flatness, sharpening the curvature constraint tot = 1.05±0.05 from WMAP alone to tot = 1.003±0.010. Assuming tot = 1, the equation of state parameter is constrained to w = −0.94±0.09, indicating the potential for more ambitious future LRG measurements to provide precision tests of the nature of dark energy. All these constraints are essentially independent of scales k > 0.1h/Mpc and associated nonlinear complications, yet agree well with more aggressive published analyses where nonlinear modeling ...


The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote Dec 2006

The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote

Articles

We examine the correlation between globular cluster (GC) color and magnitude using HST/ACS imaging for a sample of 79 early-type galaxies (−21.7 < MB < −15.2 mag) with accurate surfacebrightness fluctuation distances from the ACS Virgo Cluster Survey. Using the KMM mixture modeling algorithm, we find a highly significant correlation, z ≡ d(g−z) dz = −0.037 ± 0.004, between color and magnitude for the subpopulation of blue GCs in the co-added GC color-magnitude diagram of the three brightest Virgo cluster galaxies (M49, M87 and M60). The sense of the correlation is such that brighter GCs are redder than their fainter counterparts. For the single GC systems of M87 and M60, we find similar correlations; M49 does not appear to show a significant trend. There is no correlation between (g − z) and Mz for GCs belonging to the red subpopulation. The correlation g ≡ d(g−z) dg for the blue subpopulation is much weaker than z. Using Monte Carlo simulations, we attribute this finding to the fact that the blue subpopulation in Mg extends to higher luminosities than does the red subpopulation, which biases the KMM fit results. The highly significant correlation between color and Mz, however, is a real effect: this conclusion is supported by biweight fits to the same color distributions. We identify two environmental dependencies which influence the derived color-magnitude relation: (1) the slope of the color-magnitude relation decreases in significance with decreasing galaxy luminosity, although it remains detectable over the full luminosity range of our sample; and (2) the slope is stronger for GC populations located at smaller galactocentric distances. These characteristics suggest that the observed trend is, at least partially, shaped by external agents. We examine several physical mechanisms that might give rise to the observed color-magnitude relation including: (1) presence of contaminants like super-clusters, stripped galactic nuclei, or ultra-compact dwarfs; (2) accretion of GCs from low-mass galaxies; (3) stochastic effects; (4) the capture of field stars by individual GCs; and (5) GC self-enrichment. Although none of these scenarios offers a fully satisfactory explanation of the observations, we conclude that self-enrichment and field-star capture, or a combination of these processes, offer the most promising means of explaining our observations.


Tass Mark Iv Photometric Survey Of The Northern Sky, Thomas Droege, Michael Richmond, Michael Sallman, Robert P. Creager Dec 2006

Tass Mark Iv Photometric Survey Of The Northern Sky, Thomas Droege, Michael Richmond, Michael Sallman, Robert P. Creager

Articles

The Amateur Sky Survey (TASS) is a loose confederation of amateur and professional astronomers. We describe the design and construction of our Mark IV systems, a set of wide-field telescopes with CCD cameras which take simultaneous images in the V and IC passbands. We explain our observational procedures and the pipeline which processes and reduces the images into lists of stellar positions and magnitudes. We have compiled a large database of measurements for stars in the northern celestial hemisphere with V -band magnitudes in the range 7 < V < 13. This paper describes data taken over the four-year period starting November, 2001. One of our results is a catalog of repeated measurements on the Johnson-Cousins system for over 4.3 million stars.


When The Walls Crash Down: Offer Services Where The Students Are, Julie Arendt, Mary K. Taylor Dec 2006

When The Walls Crash Down: Offer Services Where The Students Are, Julie Arendt, Mary K. Taylor

Articles

No abstract provided.


Upper Bounds On Parity-Violating Gamma-Ray Asymmetries In Compound Nuclei From Polarized Cold Neutron Capture, M. T. Gericke, J. D. Bowman, R. D. Carlini, T. E. Chupp, K. P. Coulter, M. Dabaghyan, M. Dawkins, D. Desai, S. J. Freedman, T. R. Gentile, R. C. Gillis, G. L. Greene, F. W. Hersman, T. Ino, Gordon L. Jones, M. Kandes, B. Lauss, M. Leuschner, W. R. Lozowski, R. Mahurin, M. Mason, Y. Masuda, G. S. Mitchell, S. Muto, H. Nann, S. A. Page, S. I. Penttila, W. D. Ramsay, S. Santra, P.-N. Seo, E. I. Sharapov, T. B. Smith, W. M. Snow, W. S. Wilburn, V. Yuan, H. Zhu Dec 2006

Upper Bounds On Parity-Violating Gamma-Ray Asymmetries In Compound Nuclei From Polarized Cold Neutron Capture, M. T. Gericke, J. D. Bowman, R. D. Carlini, T. E. Chupp, K. P. Coulter, M. Dabaghyan, M. Dawkins, D. Desai, S. J. Freedman, T. R. Gentile, R. C. Gillis, G. L. Greene, F. W. Hersman, T. Ino, Gordon L. Jones, M. Kandes, B. Lauss, M. Leuschner, W. R. Lozowski, R. Mahurin, M. Mason, Y. Masuda, G. S. Mitchell, S. Muto, H. Nann, S. A. Page, S. I. Penttila, W. D. Ramsay, S. Santra, P.-N. Seo, E. I. Sharapov, T. B. Smith, W. M. Snow, W. S. Wilburn, V. Yuan, H. Zhu

Articles

Parity-odd asymmetries in the electromagnetic decays of compound nuclei can sometimes be amplified above values expected from simple dimensional estimates by the complexity of compound nuclear states. Using a statistical approach, we estimate the root-mean-square of the distribution of expected parity-odd correlations (s) over right arrow (n)center dot(k) over right arrow (gamma), where (s) over right arrow (n) is the neutron spin and (k) over right arrow (gamma) is the momentum of the gamma, in the integrated gamma spectrum from the capture of cold polarized neutrons on Al, Cu, and In. We present measurements of the asymmetries in ...


Geometry Of Minimal Flows, William Basener Dec 2006

Geometry Of Minimal Flows, William Basener

Articles

Our main result is that a minimal flow on a compact manifold is either topologically conjugate to a Riemannian flow or every parametrization of φ is nowhere equicontinuous, defined as follows. A flow is Riemannian if given any points x, y ∈ M , the value of d(φt (x), φt (y)) is independent of t ∈ R . A flow is nowhere equicontinuous if there exists an


A Lost Soul In Search Of The Light : Francois Mauriac's ''Therese Desqueyroux'', Eamon Maher Dec 2006

A Lost Soul In Search Of The Light : Francois Mauriac's ''Therese Desqueyroux'', Eamon Maher

Articles

Material reproduced by kind permission of Reality


Contribution Of Stellar Tidal Disruptions To The X-Ray Luminosity Function Of Active Galaxies, Miloš Milosavljević, David Merritt, Luis C. Ho Nov 2006

Contribution Of Stellar Tidal Disruptions To The X-Ray Luminosity Function Of Active Galaxies, Miloš Milosavljević, David Merritt, Luis C. Ho

Articles

The luminosity function of active galactic nuclei has been measured down to luminosities ∼ 1042 ergs s-1 in the soft and hard X-rays. Some fraction of this activity is associated with the accretion of the material liberated by the tidal disruption of stars by massive black holes. We estimate the contribution to the X-ray luminosity function from the tidal disruption process. While the contribution depends on a number poorly known parameters, it appears that it can account for the majority of X-ray selected AGN with soft or hard Xray luminosities . 1043 - 1044 ergs s-1. If this is correct, a picture emerges ...


The Transforming Power Of Grace, Eamon Maher Nov 2006

The Transforming Power Of Grace, Eamon Maher

Articles

Material reproduced by kind permission of Reality


There Is No 2-(22,8,4) Block Design, Richard Bilous, Clement W.H. Lam, Larry H. Thiel, Ben P.C. Li, G.H. John Van Rees, Stanislaw P. Radziszowski, Wolfgang H. Holzmann, Hadi Kharaghani Oct 2006

There Is No 2-(22,8,4) Block Design, Richard Bilous, Clement W.H. Lam, Larry H. Thiel, Ben P.C. Li, G.H. John Van Rees, Stanislaw P. Radziszowski, Wolfgang H. Holzmann, Hadi Kharaghani

Articles

In this paper we show that a 2-(22, 8, 4) design does not exist. This result was obtained by a computer search.


Trends In The Globular Cluster Luminosity Function Of Early-Type Galaxies, Andrés Jordán, Dean E. Mclaughlin, Patrick Côté, David Merritt, Et Al. Oct 2006

Trends In The Globular Cluster Luminosity Function Of Early-Type Galaxies, Andrés Jordán, Dean E. Mclaughlin, Patrick Côté, David Merritt, Et Al.

Articles

We present results from a study of the globular cluster luminosity function (GCLF) in a sample of 89 earlytype galaxies observed as part of the ACS Virgo Cluster Survey. Using a Gaussian parametrization of the GCLF, we find a highly significant correlation between the GCLF dispersion, , and the galaxy luminosity, MB,gal, in the sense that the GC systems in fainter galaxies have narrower luminosity functions. The GCLF dispersions in the Milky Way and M31 are fully consistent with this trend, implying that the correlation between sigma and galaxy luminosity is more fundamental than older suggestions that GCLF shape is ...


Youth, Governance And The City: Towards A Critical Urban Sociology Of Youth Crime And Disorder Prevention, Matt Bowden Oct 2006

Youth, Governance And The City: Towards A Critical Urban Sociology Of Youth Crime And Disorder Prevention, Matt Bowden

Articles

This article considers the historical and spatial context for the emergence of youth crime and disorder prevention initiatives in Ireland. These initiatives have to be understood in the context of their relationship to the broader ‘urban question’ and in particular the relationship of the peripheral housing estate to the rest of society and the economic sphere. More recent changes in the nature of society and the emergence of a ‘liberal creed’ have resulted in greater use of surveillance technologies for offsetting the opportunities for crime to be committed. In this context, youth crime prevention initiatives must be seen as an ...


Textual Case-Based Reasoning For Spam Filtering: A Comparison Of Feature-Based And Feature-Free Approaches, Sarah Jane Delany, Derek Bridge Oct 2006

Textual Case-Based Reasoning For Spam Filtering: A Comparison Of Feature-Based And Feature-Free Approaches, Sarah Jane Delany, Derek Bridge

Articles

Spam filtering is a text classification task to which Case-Based Reasoning (CBR) has been successfully applied. We describe the ECUE system, which classifies emails using a feature-based form of textual CBR. Then, we describe an alternative way to compute the distances between cases in a feature-free fashion, using a distance measure based on text compression. This distance measure has the advantages of having no set-up costs and being resilient to concept drift. We report an empirical comparison, which shows the feature-free approach to be more accurate than the feature-based system. These results are fairly robust over different compression algorithms in ...


Icing Location Client, Seamus Rooney, Keith Gardiner, James Carswell Oct 2006

Icing Location Client, Seamus Rooney, Keith Gardiner, James Carswell

Articles

The ICiNG (Innovative Cities for Next Generation) project is researching a multi-modal, multi-access model of e-Government. It develops the concept of a “thin-skinned City” that will be sensitive to both the citizen and the environment through the use of mobile devices, universal access gateways, social software and environmental sensors. Intelligent infrastructure will enable a Public Administration Services layer and a Communities layer. Communities will interact with the infrastructure to avail of ICiNG services created by the administration, and will also create their own information-based services.


In Vivo Mature Immunological Synapses Forming Smacs Mediate Clearance Of Virally Infected Astrocytes From The Brain, Carlos Barcia, Clare Thomas, James Curtin, Gwendalyn King, Kolja Wawrowsky, Marianela Candolfi, Weidong Xiong, Chunyan Liu, Kurt Kroeger, Olivier Boyer, Jerzy Kupiec-Weglinski, David Klatzmann, Maria Castro, Pedro Lowenstein Sep 2006

In Vivo Mature Immunological Synapses Forming Smacs Mediate Clearance Of Virally Infected Astrocytes From The Brain, Carlos Barcia, Clare Thomas, James Curtin, Gwendalyn King, Kolja Wawrowsky, Marianela Candolfi, Weidong Xiong, Chunyan Liu, Kurt Kroeger, Olivier Boyer, Jerzy Kupiec-Weglinski, David Klatzmann, Maria Castro, Pedro Lowenstein

Articles

The microanatomy of immune clearance of infected brain cells remains poorly understood. Immunological synapses are essential anatomical structures that channel information exchanges between T cell–antigen-presenting cells (APC) during the priming and effector phases of T cells' function, and during natural killer–target cell interactions. The hallmark of immunological synapses established by T cells is the formation of the supramolecular activation clusters (SMACs), in which adhesion molecules such as leukocyte function-associated antigen 1 segregate to the peripheral domain of the immunological synapse (p-SMAC), which surrounds the T cell receptor–rich or central SMAC (c-SMAC). The inability so far to detect ...


On The Autocorrelation Of Complex Envelope Of White Noise, R. Viswanathan Sep 2006

On The Autocorrelation Of Complex Envelope Of White Noise, R. Viswanathan

Articles

About four decades ago, in an article in this transactions, Thomas Kailath pointed out that the autocorrelation of the complex envelope of white noise is not strictly an impulse function, even though when treated as an impulse in practical problems, it does lead to correct results. However, it is commonly assumed that by simply letting the bandwidth of a flat-bandlimited noise process to go to infinity, one obtains the result that the autocorrelation of the complex envelope of white noise equals an impulse function. In this correspondence, we show that 1) the limit operation has to be done carefully and ...


A Hybrid Thermal Video And Ftir Spectrometer System For Rapidly Locating And Characterizing Gas Leaks, David J. Williams, Winthrop Wadsworth, Carl Salvaggio, David W. Messinger Sep 2006

A Hybrid Thermal Video And Ftir Spectrometer System For Rapidly Locating And Characterizing Gas Leaks, David J. Williams, Winthrop Wadsworth, Carl Salvaggio, David W. Messinger

Articles

Undiscovered gas leaks, known as fugitive emissions, in chemical plants and refinery operations can impact regional air quality and present a loss of product for industry. Surveying a facility for potential gas leaks can be a daunting task. Industrial leak detection and repair programs can be expensive to administer. An efficient, accurate and cost effective method for detecting and quantifying gas leaks would both save industries money by identifying production losses and improve regional air quality. Specialized thermal video systems have proven effective in rapidly locating gas leaks. These systems, however, do not have the spectral resolution for compound identification ...


Newly Identified Vitamin K-Producing Bacteria Isolated From The Neonatal Faecal Flora, Gordon Cooke, John Behan, Mary Costello Sep 2006

Newly Identified Vitamin K-Producing Bacteria Isolated From The Neonatal Faecal Flora, Gordon Cooke, John Behan, Mary Costello

Articles

Fat-soluble vitamin K is an essential component of the blood clotting process. Menaquinones are the naturally occurring form of vitamin K identified in bacteria. Lipid extracts were made from three bacteria originally isolated from the human neonatal gut and identified as Enterobacter agglomerans, Serratia marcescens and Enterococcus faecium. Following preparative thin layer chromatography (TLC), the lipid extracts were subjected to liquid chromatography-mass spectrometry (LC-MS) analysis. Peak analysis of the LC-MS data showed that the three bacteria produce various forms of menaquinone.


Review: On Audio Culture, Christopher Delaurenti Sep 2006

Review: On Audio Culture, Christopher Delaurenti

Articles

A review of the book Audio Culture edited by Christoph Cox and Daniel Warner.


Remoulding The Critical Junctures Approach, John Hogan Sep 2006

Remoulding The Critical Junctures Approach, John Hogan

Articles

This paper improves our understanding of critical junctures, a concept employed in historical institutionalism for exploring change. However, the concept lacks rigour, weakening our ability to define critical junctures. Of late, academics have utilized other mechanisms to identify change in historical institutionalism. Thus, it is within this context that the critical junctures approach is remoulded through the specification of standards, hence reducing uncertainty as to what constitutes a critical juncture. The remoulded approach is employed here in examining change in the Irish Congress of Trade Unions’ ~ICTU! influence over public policy in 1987.


V1647 Orionis: The X-Ray Evolution Of A Pre-Main-Sequence Accretion Burst, Joel Kastner, Michael Richmond, Nicolas Grosso, David A. Weintraub, Theodore Simon, Arne Henden, Kenji Hamaguchi, Hideki Ozawa Aug 2006

V1647 Orionis: The X-Ray Evolution Of A Pre-Main-Sequence Accretion Burst, Joel Kastner, Michael Richmond, Nicolas Grosso, David A. Weintraub, Theodore Simon, Arne Henden, Kenji Hamaguchi, Hideki Ozawa

Articles

We present Chandra X-ray Observatory monitoring observations of the recent accretion outburst displayed by the pre-main sequence (pre-MS) star V1647 Ori. The X-ray observations were obtained over a period beginning prior to outburst onset in late 2003 and continuing through its apparent cessation in late 2005, and demonstrate that the mean flux of the spatially coincident X-ray source closely tracked the near-infrared luminosity of V1647 Ori throughout its eruption. We find negligible likelihood that the correspondence between X-ray and infrared light curves over this period was the result of multiple X-ray flares unrelated to the accretion burst. The recent Chandra ...


Transverse Disks, Symbolic Dynamics, Homology Direction Bectors, And Thurston-Nielson Theory, William Basener Aug 2006

Transverse Disks, Symbolic Dynamics, Homology Direction Bectors, And Thurston-Nielson Theory, William Basener

Articles

We review some properties of transverse disks and use symbolic dynamics to determine rotation vectors from the return map to a transverse disk. We also prove connections between the symbolic dynamics and Nielson equivalence of orbits.


Small Ramsey Numbers, Stanislaw Radziszowski Aug 2006

Small Ramsey Numbers, Stanislaw Radziszowski

Articles

We present data which, to the best of our knowledge, includes all known nontrivial values and bounds for specific graph, hypergraph and multicolor Ramsey numbers, where the avoided graphs are complete or complete without one edge. Many results pertaining to other more studied cases are also presented. We give references to all cited bounds and values, as well as to previous similar compilations. We do not attempt complete coverage of asymptotic behavior of Ramsey numbers, but concentrate on their specific values.


Effect Of Ozone And Calcium Lactate Treaments On Browning And Textured Properties Of Fresh-Cut Lettuce, Daniel Rico, Ana Belen Martin-Diana, Gary Henehan, Jesus Maria Frias, Catherine Barry-Ryan Aug 2006

Effect Of Ozone And Calcium Lactate Treaments On Browning And Textured Properties Of Fresh-Cut Lettuce, Daniel Rico, Ana Belen Martin-Diana, Gary Henehan, Jesus Maria Frias, Catherine Barry-Ryan

Articles

The effects of three treatments, 1 mg L−1 ozone at 18–20 °C, 15 g L−1 calcium lactate (CLac) at 50 °C and a combination thereof, were compared on fresh-cut lettuce over 10 days of refrigerated storage. Respiration rate, browning and texture were examined as main quality indicators. The use of ozone produced a significantly (P < 0.05) higher oxygen decline than the use of CLac (from day 3 to day 10). At the end of storage, CLac (alone or combined with ozone) samples had higher oxygen content (∼9%) than ozone samples (∼6%). Enzymatic activity decreased significantly (P < 0.05) in ozone samples. Polyphenol oxidase activity in fresh-cut lettuce treated with ozone (alone or combined with CLac) showed lower values on day 1 (−1) and at the end of storage (g−1) than CLac samples (4000–4800 units g−1). Ozone also reduced peroxidase activity to ∼300 units g−1 after treatment. Finally, pectin methylesterase activity was also reduced with ozone, showing a negative effect on textural properties. Data suggested that CLac ...


The Quality Movement Discourse In The Higher Education Sector: A General Review, Aidan Kenny Aug 2006

The Quality Movement Discourse In The Higher Education Sector: A General Review, Aidan Kenny

Articles

This paper – the first of a series of three – describes some of the macro milestones in the evolution of the Quality Movement in the industrial environment. The emphasis then shifts to reviewing the discourse relating to quality in the higher education sector in the UK. Attention is given to Quality Assessment, Quality Assurance and Quality Enhancement models. The interface or tension lines between quality as a controlling mechanism or as a tool for development are outlined. Predominant concerns and issues as expressed by academics are clustered into macro questions, the answers to which will require further longitudinal research.


The Emergence Of Quality Assurance In Irish Higher Education: A Review Of European And National Policy And Description Of The Dublin Institute Of Technology Practice, Aidan Kenny Aug 2006

The Emergence Of Quality Assurance In Irish Higher Education: A Review Of European And National Policy And Description Of The Dublin Institute Of Technology Practice, Aidan Kenny

Articles

This is the second in a series of three papers which explore and describe ‘quality’ as a tool in the Irish Higher Education sector. This paper reviews macro, mesco and micro issues relating to quality assurance within the context of European Union Education Ministers’ communiqués and in Irish national policy. A micro perspective is then undertaken pertaining to the Dublin Institute of Technology describing how quality assurance systems and procedures emerged in the Institute. It also includes the Institute’s response to provisions made in the 1999 Qualifications (Education and Training) Act with reference to the necessity of carrying out ...


What Light Do Professional Doctorates Throw On The Question Of What Counts As Knowledge In The Academy At The Start Of The Twenty-First Century?, Sandra Fisher Aug 2006

What Light Do Professional Doctorates Throw On The Question Of What Counts As Knowledge In The Academy At The Start Of The Twenty-First Century?, Sandra Fisher

Articles

In their article, ‘Professional Doctorates in England’, Bourner et al. (2001: 81) pose the question ‘What light do professional doctorates throw on the question of what counts as knowledge in the academy at the start of the twenty-first century?’ This article attempts to address this question. The article provides some background to the development of professional doctorates. It looks at forces, such as the rise of the knowledge society, economic drivers, and the demands of lifelong learning, that are shaping knowledge in the academy in the twenty-first century. I attempt to interpret these forces in the context of the development ...