7,488 research outputs found

    Correlation of Hydronephrosis Index to Society of Fetal Urology Hydronephrosis Scale

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    Purpose. We seek to correlate conventional hydronephrosis (HN) grade and hydronephrosis index (HI). Methods. We examined 1207 hydronephrotic kidneys by ultrasound. HN was classified by Society of Fetal Urology guidelines. HN was then gauged using HI, a reproducible, standardized, and dimensionless measurement of renal area. We then calculated average HI for each HN grade. Results. Comparing HI to standard SFU HN grade, average HI is 89.3 for grade I; average HI is 83.9 for grade II; average HI is 73.0 for grade III; average HI is 54.6 for SFU grade IV. Conclusions. HI correlates well with SFU HN grade. The HI serves as a quantitative measure of HN. HI can be used to track HN over time. Versus conventional grading, HI may be more sensitive in defining severe (grades III and IV) HN, and in indicating resolving, stable, or worsening HN, thus providing more information for clinical decision-making and HN management

    Bostonia. Volume 4

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    Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

    Circular Dichroism of Bufadienolides

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    With the help of PMO theory a non-empirical sector rule has been derived for the n ~ 1t5* band CD (around 260 nm) of the pentadienolide chromophore of steroidal bufadienolides. The rule was verified by experiment using the preferred conformation for the 2-pyrone side chain found in most of the crystalline bufadienolides investigated by x-ray diffraction. Substituents in ring D do not drastically influence the Cotton effect of this transition, whereas the sign of the 1C4 ~ 1t5* band Cotton effect around 300 nm is strongly dependent on such substitutions. The Cotton effect of additional carbonyl groups can in general be detected without difficulty in the CD-spectra

    Supernova Remnants in the Fossil Starburst in M82

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    We report the discovery of ten compact H-alpha-bright sources in the post-starburst region northeast of the center of M82, ``M82 B.'' These objects have H alpha luminosities and sizes consistent with Type II supernova remnants (SNRs). They fall on the same H alpha surface brightness-diameter (Sigma-D) relation defined by SNRs in other nearby star-forming galaxies, with the M82 candidates lying preferentially at the small diameter end. These are the first candidates for optically-visible SNRs in M82 outside the heavily obscured central starburst within ~250 pc from the galactic center. If these sources are SNRs, they set an upper limit to the end of the starburst in region ``B2,'' about 500 pc from the galaxy's core, of ~50 Myr. Region ``B1,'' about 1000 pc from the core, lacks good SNR candidates and is evidently somewhat older. This suggests star formation in the galaxy has propagated inward toward the present-day intense starburst core.Comment: Re-submitted to AJ, referee's comments taken into account, 15 pages LaTeX preprint style, 4 postscript figures; full-resolution figures available from http://www.astro.virginia.edu/~rd7a/snrs/ Changes: minor textual changes and orientation/axes of Fig.

    Fe XXV and Fe XXVI Diagnostics of the Black Hole and Accretion Disk in Active Galaxies: Chandra Time-Resolved Spectroscopy of NGC 7314

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    We report the detection of Fe XXV and Fe XXVI KαK\alpha emission lines from a Chandra HETGS observation of the Seyfert~1 galaxy NGC 7314, made simultaneously with RXTE. The lines are redshifted (cz ~ 1500 km/s) relative to the systemic velocity and unresolved. We argue that the lines originate in a near face-on (<7 degrees) disk having a radial line emissivity flatter than r^-2. Line emission from ionization states of Fe in the range ~Fe I up to Fe XXVI is observed. The ionization balance of Fe responds to continuum variations on timescales less than 12.5 ks, supporting an origin of the lines close to the X-ray source. We present additional, detailed diagnostics from this rich data set. These results identify NGC 7314 as a key source to study in the future if we are to pursue reverberation mapping of space-time near black-hole event horizons. This is because it is first necessary to understand the ionization structure of accretion disks and the relation between the X-ray continuum and Fe K line emission. However, we also describe how our results are suggestive of a means of measuring black-hole spin without a knowledge of the relation between the continuum and line emission. Finally, these data emphasize that one {\it can} study strong gravity with narrow (as opposed to very broad) disk lines. In fact narrow lines offer higher precision, given sufficient energy resolution.Comment: Accepted for publication in the Astrophysical Journal. 30 pages, six figures, five of them color. Abstract is abridge

    Retail and Community: Business, Charity and the End of Empire

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    Retail has never existed in a vacuum. This interdisciplinary volume explores how English commercial, co-operative and charity retailing were shaped by and in turn influenced their social and political environments, from the local and the global, between the late-nineteenth and early twenty-first centuries. Historians, sociologists, archivists and heritage professionals engage with current debates on the rise of modern business and the decline of the high street, class and credit, professionalisation in the voluntary sector, migration and the end of empire. This will be a key resource to better understand retail and community in an era defined by social change, shedding new light on the enduring centrality of community relationships to modern retailers

    Impact of the ASCO 2007 Presentation of HOG Lun 01-24/USO-023 on the Prescribing Plans of American Medical Oncologists for Patients with Stage IIIB Non-small Cell Lung Cancer

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    Introduction:Nonoperative treatment of stage III non-small cell lung cancer has evolved over the past 30 years. The current approach in the Unites States most often includes concurrent chemoradiotherapy.Methods:We have used live, case-based research events to document prescribing plans among American medical oncologists for first-line therapy in patients with N3 stage IIIB non-small cell lung cancer. Changes in prescribing plans documented before and after the 2007 American Society of Clinical Oncology (ASCO) presentation of a Hoosier Oncology Group trial testing the role of consolidation docetaxel chemotherapy in this setting are presented.Results:Data from 2007 show a post-ASCO shift away from plans for docetaxel consolidation, increased use of concurrent chemoradiotherapy alone, and stable to increased plans for concurrent chemoradiation followed by additional cycles of the chemotherapy used during concurrent management (20%). Preliminary data from 2008 confirm the durability of these changes.Conclusions:The findings of the Hoosier Oncology Group trial support a transition away from docetaxel consolidation. A trend in this direction among American medical oncologists is clear from our data. However, nearly 20% of oncologists studied in 2008 still plan to use docetaxel consolidation. Furthermore, a majority of those studied after ASCO 2007 continue to report plans to use more than two cycles of chemotherapy as part of their preferred treatment recommendation despite no level I evidence to support this approach

    New constraints on the continuum-emission mechanism of AGN: Intensive monitoring of NGC 7469 in the X-ray and ultraviolet

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    We have undertaken near-continuous monitoring of the Seyfert 1 galaxy NGC 7469 in the X-ray with RXTE over a ~30d baseline. The source shows strong variability with a root-mean-square (rms) amplitude of ~16 per cent, and peak-to-peak variations of a factor of order 2. Simultaneous data over this period were obtained in the ultraviolet (UV) using IUE, making this the most intensive X-ray UV/X-ray variability campaign performed for any active galaxy. Comparison of the continuum light curves reveals very similar amplitudes of variability, but different variability characteristics, with the X-rays showing much more rapid variations. The data are not strongly correlated at zero lag. The largest absolute value of the correlation coefficient occurs for an anticorrelation between the two bands, with the X-ray variations leading the UV by ~4d. The largest positive correlation is for the ultraviolet to lead the X-rays by ~4d. Neither option appears to be compatible with any simple interband transfer function. The peak positive correlation at ~4d occurs because the more prominent peaks in the UV light curve appear to lead those in the X-rays by this amount. However, the minima of the light curves are near-simultaneous. These observations provide new constraints on theoretical models of the central regions of active galactic nuclei. Models in which the observed UV emission is produced solely by re-radiation of absorber X-rays are ruled out by our data, as are those in which the X-rays are produced solely by Compton upscattering of the observed UV component by a constant distribution of particles.Comment: 33 pages, 8 figures. LaTeX with encapsulated postscript. To appear in the Astrophysical Journal. Also available via http://lheawww.gsfc.nasa.gov/users/nandra/pubs/7469/abstract.htm

    An Exploratory Investigation on the Invasiveness of Environmental Modeling Frameworks

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    Environmental modeling frameworks provide an array of useful features that model developers can harness when implementing models. Each framework differs in how it provides features to a model developer via its Application Programming Interface (API). Environmental modelers harness framework features by calling and interfacing with the framework API. As modelers write model code, they make framework-specific function calls and use framework specific data types for achieving the functionality of the model. As a result of this development approach, model code becomes coupled with and dependent on a specific modeling framework. Coupling to a specific framework makes migration to other frameworks and reuse of the code outside the original framework more difficult. This complicates collaboration between model developers wishing to share model code that ma y have been developed in a variety of languages and frameworks. This paper provides initial results of an exploratory investigation on the invasiveness of environmental modeling frameworks. Invasiveness is defined as th e coupling between application (i.e., model) and framework code used to implement the model. By comparing the implementation of an environmental model across several modeling frameworks, we aim to better understand the consequences of framework design. How frameworks present functionality to modelers through APIs can lead to consequences with respect to model development, model maintenance, reuse of model code, and ultimately collaboration among model developers. By measuring framework invasiveness, we hope to provide environmental modeling framework developers and environmental modelers with valuable in formation to assist in future development efforts. Eight implementations (six framework-based) of Thornthwaite, a simple water balance model, were made in a variety of environmental modeling frameworks and languages. A set of software metrics were proposed and applied to measure invasiveness between model implementation code and framework code. The metrics produced a rank ordering of invasiveness for the framework-based implementations of Thornthwaite. We compared model invasiveness results with several popular software metrics including size in lines of code (LOC), cyclomatic complexity, and object oriented coupling. To investigate software quality implications of framework invasiveness we checked for relationships between the Chidamber and Kemerer (1994) object oriented software metrics and our framework invasiveness measures. For the six framework-based implementations of Thornthwaite we found a five-fold variation in code size (LOC). We observed up to a seven-fold variation in total cyclomatic complexity, and a two to three-fold variation in object oriented coupling. For the model implementations we found that total size, total complexity, and total coupling all had a significant positive correlation. The raw count version of our invasiveness measures correlated with application size (LOC), total cyclomatic complexity, total efferent coupling (fan out) and total afferent coupling (fan in). Large size, complexity, and high levels of coupling between units (classes, modules) in a software system are often cited in software engineering as causes of high maintenance costs due to poor understandability and flexibility of the code. This study provides initial results but further investigation is desired to evaluate the utility of our invasiveness measurement approach as well as the software quality implications of framework invasiveness
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