6,654 research outputs found
Three-loop HTL QCD thermodynamics
The hard-thermal-loop perturbation theory (HTLpt) framework is used to
calculate the thermodynamic functions of a quark-gluon plasma to three-loop
order. This is the highest order accessible by finite temperature perturbation
theory applied to a non-Abelian gauge theory before the high-temperature
infrared catastrophe. All ultraviolet divergences are eliminated by
renormalization of the vacuum, the HTL mass parameters, and the strong coupling
constant. After choosing a prescription for the mass parameters, the three-loop
results for the pressure and trace anomaly are found to be in very good
agreement with recent lattice data down to , which are
temperatures accessible by current and forthcoming heavy-ion collision
experiments.Comment: 27 pages, 11 figures; corresponds with published version in JHE
Integrating modes of policy analysis and strategic management practice : requisite elements and dilemmas
There is a need to bring methods to bear on public problems that are inclusive, analytic, and quick. This paper describes the efforts of three pairs of academics working from three different though complementary theoretical foundations and intervention backgrounds (i.e., ways of working) who set out together to meet this challenge. Each of the three pairs had conducted dozens of interventions that had been regarded as successful or very successful by the client groups in dealing with complex policy and strategic problems. One approach focused on leadership issues and stakeholders, another on negotiating competitive strategic intent with attention to stakeholder responses, and the third on analysis of feedback ramifications in developing policies. This paper describes the 10 year longitudinal research project designed to address the above challenge. The important outcomes are reported: the requisite elements of a general integrated approach and the enduring puzzles and tensions that arose from seeking to design a wide-ranging multi-method approach
Birth data accessibility via primary care health records to classify health status in a multi-ethnic population of children: an observational study
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Is thirty-seven years sufficient for full return of the ant biota following restoration?
Introduction: An assessment of whether rehabilitated mine sites have resulted in natural or novel ecosystems requires monitoring over considerable periods of time or the use of space-for-time substitution (chronosequence) approaches. Methods: To provide an assessment of ecosystem recovery in areas mined for bauxite in 1975, the ant fauna of one area planted with Eucalyptus resinifera, one seeded with mixed native species, one topsoiled but unrestored, and a forest reference was subjected to a ‘long-term’ study by sampling monthly and latterly annually between 1976 and 1989 using pitfall traps. These plots were resampled in 2012. A companion ‘short-term’ chronosequence study was performed in 1979 in 28 bauxite mines of various ages and restored by a range of different methods, plus three forest references. In order to examine the assertion that the observed differences between restored areas and forest references will lessen with time, sampling using comparable methods was repeated in 2012 in seven of the original plots, representing progressive advances in rehabilitation technology: planted pines; planted eastern states eucalypts; planted native eucalypts; planted eucalypts over seeded understorey; and planted eucalypts on fresh, double-stripped topsoil, plus two forest reference sites. Results: Ant and other invertebrate richness in the long-term study was initially superior in the seeded plot, with little difference between the planted and unplanted plots. It was concluded that although composition of the ant fauna had converged on that of the forest over the 14-year period, differences still persisted.The 2012 resampling revealed that ant species richness and composition had deteriorated in the seeded plot, while values in the unplanted plot, which now supported naturally colonised trees and an understorey, had increased. Differences between all rehabilitated plots and forest still persisted. As with the long-term study, the rate of fauna return and the type of ants present in the short-term study plots differed with the method of rehabilitation used, and, in 1979, no plots had converged on the forest in terms of the ant assemblage. By 2012 ant richness increased, and more so with each advance in rehabilitation technology, except for seeding, in which the understorey had collapsed. Double-stripping of topsoil resulted in the greatest improvements in ant species richness, although none of the areas had converged on the forest reference areas in terms of assemblage composition or ant functional group profiles. Furthermore, assemblage composition in the forest had changed over time, possibly due to reductions in rainfall, which further complicates rehabilitation objectives. Conclusions: It is concluded that although rehabilitation can achieve its objective of restoring diversity, the original assemblage has still not been achieved after 37 years, suggesting that a degree of novelty has been introduced into these older-style rehabilitated areas. The company’s current rehabilitation practices reflect multiple advances in their approach, lending optimism that current restoration may achieve something close to the original ecosystem, an outcome that can only be verified by extended studies like the one described here
Ultrasonic tomographic imaging of defects in industrial materials
Ultrasonic tomography has been fairly widely applied for imaging of inhomogeneities in isotropic materials, particularly in the medical field, however, little success has been made in its application to industrial materials. This is largely due to the complex nature of ultrasonic wave propagation in these anisotropic materials. The three dimensional characteristics of ultrasonic wave propagation in anisotropic materials have been thoroughly studied for single crystals and also studied recently for different composites [1,2,3]. Understanding these characteristics provides the theoretical background for developing appropriate ultrasonic tomographic imaging methods for industrial materials
Mathematical Modelling of Optical Coherence Tomography
In this chapter a general mathematical model of Optical Coherence Tomography
(OCT) is presented on the basis of the electromagnetic theory. OCT produces
high resolution images of the inner structure of biological tissues. Images are
obtained by measuring the time delay and the intensity of the backscattered
light from the sample considering also the coherence properties of light. The
scattering problem is considered for a weakly scattering medium located far
enough from the detector. The inverse problem is to reconstruct the
susceptibility of the medium given the measurements for different positions of
the mirror. Different approaches are addressed depending on the different
assumptions made about the optical properties of the sample. This procedure is
applied to a full field OCT system and an extension to standard (time and
frequency domain) OCT is briefly presented.Comment: 28 pages, 5 figures, book chapte
Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe
Acknowledgements We thank the Archaeological State Museum Schleswig-Holstein, the Archaeological State Offices of Brandenburg, Lower Saxony and Saxony and the following individuals who provided sample material: Betty Arndt, Jo¨rg Ewersen, Frederick Feulner, Susanne Hanik, Ru¨diger Krause, Jochen Reinhard, Uwe Reuter, Karl-Heinz Ro¨hrig, Maguerita Scha¨fer, Jo¨rg Schibler, Reinhold Schoon, Regina Smolnik, Thomas Terberger and Ingrid Ulbricht. We are grateful to Ulrich Schmo¨lcke, Michael Forster, Peter Forster and Aikaterini Glykou for their support and comments on the manuscript. We also thank many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¨r Naturkunde, Berlin; Muse´um National d0 Histoire Naturelle, Paris; Smithsonian Institution, National Museum of Natural History, Washington D.C.; Zoologische Staatssammlung, Mu¨nchen; Museum fu¨r Haustierkunde, Halle; the American Museum of Natural History, New-York. This work was funded by the Graduate School ‘Human Development in Landscapes’ at Kiel University (CAU) and supported by NERC project Grant NE/F003382/1. Radiocarbon dating was carried out at the Leibniz Laboratory, CAU. This work is licensed under a Creative Commons AttributionNonCommercial-NoDerivs 3.0 Unported License.Peer reviewedPublisher PD
Unbiased estimate of the epithelial cell number and epithelial cell nuclear volume in the bulbourethral (cowper) glands of holstein bulls - a stereological study
The bulbourethral gland (or Cowper"s gland) plays an important role for fertility. It is, therefore, essential to have quantitative data
about the morphological and histomorphological structure of this gland in nonpathological conditions. In the present study, Holstein
bull"s bulbourethral glands were collected, and the volume of the glands, total epithelial cell number and epithelial cell"s nuclear
volume was estimated for the first time by stereological methods. The smooth fractionator technique for epithelial cell counting was
used. Epithelial cell"s nuclear volume was estimated on vertical sections. The mean number of the epithelial cells (coefficient of error;
CE) and the mean epithelial cell"s nuclear volume were found 322x107
(0.1) and 59.1 µm3
(SD=3.7) respectively. Finally, the present
studies stereological findings are in the acceptable range
Candida esophageal perforation and esophagopleural fistula: a case report
<p>Abstract</p> <p>Introduction</p> <p>Esophageal perforation is a rare disease, which can lead to significant morbidity and mortality. Its clinical presentation can mimic other disease processes and, therefore, it can be easily misdiagnosed. <it>Candida </it>infection of the esophagus is an extremely rare cause of esophageal perforation.</p> <p>Case presentation</p> <p>We report the youngest pediatric case in the medical literature of spontaneous esophageal perforation and an esophagopleural fistula due to <it>Candida </it>infection.</p> <p>Conclusion</p> <p>A high index of suspicion, especially in the presence of <it>Candida </it>empyema and the absence of disseminated infection, should raise the possibility of esophageal perforation with esophagopleural fistula formation. This can lead to early diagnosis and surgical intervention, which would decrease the high mortality rate of this rare condition.</p
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