7,116 research outputs found
Histopathology of postpercutaneous transluminal coronary angioplasty remodeling in human coronary arteries
No full textBACKGROUND:
We studied the histomorphometric correlates of long-term successful coronary balloon angioplasty (percutaneous transluminal coronary angioplasty [PTCA]). Restenosis after PTCA may occur secondary to the failure of compensatory arterial enlargement or post-PTCA arterial constriction. The histopathology of this process in human subjects remains poorly defined.
METHODS:
Forty-two coronary segments from 41 patients treated with PTCA 60 +/- 58 weeks before death were studied. The histomorphometric findings at the PTCA site were compared with those obtained at a proximal reference site.
RESULTS:
Histologic long-term success was seen in 18 (43%) of 42 arteries. Histologically successful PTCA arteries (PTCA site lumen of >/=50% of the reference lumen) demonstrated a larger acute lumen, smaller plaque size (normalized to the internal elastic lamina area), and thinner adventitia compared with histologic failures. Relative to the reference sites, histologically successful PTCA showed expansion of the external elastic lamina. In contrast, histologic failures showed a reduced external elastic lamina area, suggesting constrictive remodeling. Neointimal area correlated with the extent of internal elastic lamina disruption, but neither variable was related to histologic PTCA success or failure.
CONCLUSIONS:
These data provide histomorphometric confirmation of the hypothesis that constrictive remodeling, not neointimal formation, determines the long-term outcome of PTCA
On the AJ Conjecture for Knots
No full textWe confirm the AJ conjecture [Ga2] that relates the A-polynomial and the colored Jones polynomial for hyperbolic knots satisfying certain conditions. In particular, we show that the conjecture holds true for some classes of two-bridge knots and pretzel knots. This extends the result of the first author in [Le2], who established the AJ conjecture for a large class of two-bridge knots, including all twist knots. Along the way, we explicitly calculate the universal SL₂(C)-character ring of the knot group of the (−2, 3, 2n + 1)-pretzel knot, and show it is reduced for all integers n
Revision of the Indian Ocean dottyback fish genera <em>Chlidichthys</em> and <em>Pectinochromis</em> (Perciformes: Pseudochromidae: Pseudoplesiopinae)
No full textChlidichthys Smith includes the following 13 species: C. abruptus Lubbock (St Brandon’s Shoals); C. auratus Lubbock (Red Sea); C. bibulus (Smith) (east coast of Africa, Aldabra and Socotra); C. cacatuoides Gill & Randall (Socotra and southern Oman); C. chagosensis new species (Chagos Archipelago); C. clibanarius new species (Comoros Ids, Madagascar and Aldabra); C. foudioides new species (Rodrigues); C. inornatus Lubbock (Maldive Ids and Sri Lanka); C. johnvoelckeri Smith (Comoros Ids and Tanzania to Mozambique, East Africa); C. pembae Smith (Comoros Ids and Tanzania to Natal, East Africa); C. randalli Lubbock (Mauritius); C. rubiceps Lubbock (Red Sea); C. smithae Lubbock (Mauritius). Pectinochromis Gill & Edwards includes a single species: P. lubbocki (Edwards & Randall) (Red Sea)
Discovery of a single faint AGN in a large sample of z > 5 Lyman break galaxies
No full textAs part of a large spectroscopic survey of z > 5 Lyman break galaxies (LBGs), we have identified a single source which is clearly hosting an active galactic nucleus (AGN). Out of a sample of more than 50 spectroscopically confirmed R-band dropout galaxies at z∼ 5 and above, only J104048.6−115550.2 at z= 5.44 shows evidence for a high ionization potential emission line indicating the presence of a hard ionizing continuum from an AGN. Like most objects in our sample the rest-frame-UV spectrum shows the UV continuum breaking across a Lyα line. Uniquely within this sample of LBGs, emission from N V is also detected, a clear signature of AGN photoionization. The object is spatially resolved in Hubble Space Telescope (HST) imaging. This, and the comparatively high Lyα/N V flux ratio indicates that the majority of the Lyα (and the UV continuum longward of it) originates from stellar photoionization, a product of the ongoing starburst in the LBG. Even without the AGN emission, this object would have been photometrically selected and spectroscopically confirmed as a Lyman break in our survey. The measured optical flux (IAB= 26.1) is therefore an upper limit to that from the AGN and is of order 100 times fainter than the majority of known quasars at these redshifts. The detection of a single object in our survey volume is consistent with the best current models of high redshift AGN luminosity function, providing a substantial fraction of such AGN is found within luminous starbursting galaxies. We discuss the cosmological implications of this discovery
Correction to: Latitudinal variation in monthly-scale reproductive synchrony among Acropora coral assemblages in the Indo-Pacific (Coral Reefs, (2021), 10.1007/s00338-021-02129-3)
No full text\ua9 The Author(s) 2021.The article Latitudinal variation in monthly-scale reproductive synchrony among Acropora coral assemblages in the Indo-Pacific, written by Jessica Bouwmeester, Alasdair J. Edwards, James R. Guest, Andrew G. Bauman, Michael L. Berumen, Andrew H. Baird, was originally published electronically on the publisher’s Internet portal on 15 June, 2021 without open access. With the author(s)’ decision to opt for Open Choice, the copyright of the article changed on 17 June, 2021 to The Author(s) 2021 and the article is forthwith distributed under a Creative Commons Attribution.
The author, the text, and the (post)critic: notes on the encounter between postcritique and postcolonial criticism
No full textThe article confronts postcolonial criticism with postcritique, a proposal by Rita Felski for a hermeneutic strategy aiming to overcome the limits of critique. Because of its self-reflexivity, its liaison with poststructuralism, and the societal categories it mobilizes, postcritics often see postcolonial criticism as a quintessential example of critique. However, postcolonial authors share similar concerns as postcritics, particularly when warning against any hasty conflation between intellectual work and political commitment. This article argues that the postcritical understanding of critique eschews the connection between critique and the realm of culture, thereby running the risk of doing away with context altogether. In order to account for the frameworks or contexts in which cultural objects are produced, without falling into some of the pitfalls of critique that postcritique aims to counter, the article proposes to look at the figure of the author as a bridge between the individual and the collective, as Edward Said suggests. The article closes with an analysis of several (critical and postcritical) readings of J. M. Coetzee’s The Childhood of Jesus to provide an example of how authorship can enter the interpretive scene through the figure of ‘late style’
Exploring the roles, effectiveness and impact of health information professionals within evidence based practice
No full textThis is the thesis (critical appraisal) component of a PhD by Published Works. The overall submission was a portfolio of ten published papers supported by a critical appraisal focusing on two key areas: an exploration of the roles that Health Information Professionals (HIPs) can play within evidence based practice (EBP) and an exploration of the effectiveness and impact of the traditional supportive role played by HIPs within EBP. The published papers are listed and referenced within this document but not contained within it. The majority are available elsewhere within the University of Salford Institutional Repository.Drawing on a model developed from the library literature, the thesis highlights a wide range of supportive and active roles that HIPs can potentially play within EBP. This model is informed and illuminated by the studies within the portfolio that demonstrate how the author has fulfilled a wide range of these roles in practice, and identified a new role within systematic reviews in health and social care. This demonstrates that HIPs can transfer their skills outside their traditional library and information practice domain, thus extending theirrole and offering a range of professional opportunities.Using a varied range of research methodologies, the thesis also explores the effectiveness and impact of the contribution made by HIPs when using traditional skills to support EBP. Two models are used to illustrate the outcomes to which HIPs contribute. These include improving search skills and providing evidence which can, over the longer term, contribute to policy making and patient care. At present the weight of the evidence presented tosupport these links is weak. Methodological issues and future research that needs to be addressed to improve the strength of the evidence base are therefore highlighted and discussed
The XMM-Newton long look of NGC 1365: uncovering of the obscured X-ray source
No full textWe present an analysis of the extreme obscuration variability observed during an XMM–Newton 5-d continuous monitoring of the active galactic nuclei (AGN) in NGC 1365. The source was in a reflection-dominated state in the first ∼1.5 d, then a strong increase in the 7–10 keV emission was observed in ∼10 h, followed by a symmetric decrease. The spectral analysis of the different states clearly shows that this variation is due to an uncovering of the X-ray source. From this observation, we estimate a size of the X-ray source DS < 1013 cm, a distance of the obscuring clouds R∼ 1016 cm and a density n∼ 1011 cm−3. These values suggest that the X-ray absorption/reflection originates from the broad-line region clouds. This is also supported by the resolved width of the iron narrow Kα emission line, consistent with the width of the broad Hβ line
Galaxy Zoo:chiral correlation function of galaxy spins
No full textGalaxy Zoo is the first study of nearby galaxies that contains reliable information about the spiral sense of rotation of galaxy arms for a sizeable number of galaxies. We measure the correlation function of spin chirality (the sense in which galaxies appear to be spinning) of face-on spiral galaxies in angular, real and projected spaces. Our results indicate a hint of positive correlation at separations less than ~0.5 Mpc at a statistical significance of 2-3 sigma. This is the first experimental evidence for chiral correlation of spins. Within tidal torque theory it indicates that the inertia tensors of nearby galaxies are correlated. This is complementary to the studies of nearby spin axis correlations that probe the correlations of the tidal field. Theoretical interpretation is made difficult by the small distances at which the correlations are detected, implying that substructure might play a significant role, and our necessary selection of face-on spiral galaxies, rather than a general volume-limited sample
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