585 research outputs found
Magnetic properties of Hydrogenated Li and Co doped ZnO nanoparticles
The effect of hydrogenation on magnetic properties of Zn0.85Co0.05Li0.10O
nanoparticles is presented. It was found that the sample hydrided at room
temperature (RT) showed weak ferromagnetism (FM) while that hydrided at 400oC
showed robust ferromagnetism at room temperature. In both cases reheating the
sample at 400oC in air converts it back into paramagnetic state (P) completely.
The characterization of samples by X-ray and electron diffraction (ED) showed
that room temperature ferromagnetism observed in the samples hydrogenated at RT
is intrinsic in nature whereas that observed in the samples hydrogenated at
400oC is partly due to the cobalt metal clusters.Comment: 10 pages, 3 figure
Room temperature Ferromagnetism in Th1-xFexO2-d (x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) nanoparticles
Nanocrystalline (Th1-xFex)O2-d particles with different Fe concentrations (x
= 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) have been prepared by a gel combustion
method. Rietveld refinement analyses of X-ray diffraction data revealed the
formation of an impurity free cubic type Th1-xFexO2-d structure up to x = 0.20.
This observation is further confirmed from the detailed studies conducted on 10
at. percent Fe doped ThO2 using high-resolution transmission electron
microscopy (HRTEM) imaging and indexing of the selected-area electron
diffraction (SAED) patterns. DC Magnetization studies as a function field
indicate that they are ferromagnetic with Curie temperature (Tc) well above
room temperature.Comment: 10 pages, 5 figure
Chitosan nanocomposites based on distinct inorganic fillers for biomedical applications
AbstractChitosan (CHI), a biocompatible and biodegradable polysaccharide with the ability to provide a non-protein matrix for tissue growth, is considered to be an ideal material in the biomedical field. However, the lack of good mechanical properties limits its applications. In order to overcome this drawback, CHI has been combined with different polymers and fillers, leading to a variety of chitosan-based nanocomposites. The extensive research on CHI nanocomposites as well as their main biomedical applications are reviewed in this paper. An overview of the different fillers and assembly techniques available to produce CHI nanocomposites is presented. Finally, the properties of such nanocomposites are discussed with particular focus on bone regeneration, drug delivery, wound healing and biosensing applications
The structural and magnetic properties of (In1-xFex)2O3 (0.0 <= x <= 0.25) system : prepared by gel combustion method
(In1-xFex)2O3 polycrystalline samples with x = (0.0, 0.05, 0.10, 0.15, 0.20
and 0.25) have been synthesized by a gel combustion method. Reitveld refinement
analysis of X raydiffraction data indicated the formation of single phase cubic
bixbyite structure without any parasitic phases. This observation is further
confirmed by high resolution transmission electron microscopy (HRTEM) imaging,
and indexing of the selected-area electron diffraction (SAED) patterns, X-ray
Absorption Spectroscopy (XAS) and Raman Spectroscopy. DC Magnetization studies
as a function of temperature and field indicatethat they are ferromagnetic with
Curie temperature (TC) well above room temperature.Comment: 9 pages 3 figure
Proceedings of the 2015 WA Chapter of MSA Symposium on Music Performance and Analysis
This publication, entitled Proceedings of the 2015 WA Chapter MSA Symposium on Music Performance and Analysis, is a double-blind peer-reviewed conference proceedings published by the Western Australian Chapter of the Musicological Society of Australia, in conjunction with the Western Australian Academy of Performing Arts, Edith Cowan University, edited by Jonathan Paget, Victoria Rogers, and Nicholas Bannan. The original symposium was held at the University of Western Australia, School of Music, on 12 December 2015.
With the advent of performer-scholars within Australian Universities, the intersections between analytical knowledge and performance are constantly being re-evaluated and reinvented. This collection of papers presents several strands of analytical discourse, including: (1) the analysis of music recordings, particularly in terms of historical performance practices; (2) reinventions of the \u27page-to-stage\u27 paradigm, employing new analytical methods; (3) analytical knowledge applied to pedagogy, particularly concerning improvisation; and (4) so-called \u27practice-led\u27 research.https://ro.ecu.edu.au/ecubooks/1005/thumbnail.jp
How do surgeons decide? Conduit choice in coronary artery bypass graft surgery in the UK
OBJECTIVES
Conduits used in coronary artery bypass grafting may have significant impact on outcomes, but evidence is mixed and there is large variation in practice. This study provides insights into the opinions of the UK surgeons on conduit use and their decision-making processes.
METHODS
A questionnaire was created using the Ottawa Decision Support Framework to elicit the importance that surgeons placed on bilateral internal mammary artery grafting, skeletonization, total arterial revascularization and sequential anastomoses on a scale of 1–10. Scores ≥8 were deemed ‘important’ and ≤3 ‘not important’. Surgeons were asked to specify changes to practice in frail patients or emergencies. Additional questions included conduit type used, factors affecting decision-making and vein harvesting methods. Questionnaires were administered in person with data analysed centrally.
RESULTS
Ninety-seven consultant cardiac surgeons from 25 centres responded. Thirty-two percent surgeons routinely used radial arteries and 36% used right internal mammary artery. High-quality evidence contributed most to decision-making receiving a total of 328/960 points, with consultant experience being the second (255/960 points). There was a bimodal distribution of perceived importance of bilateral internal mammary artery use, with 29 (30%) ‘important’ and ‘not important’ scores each. 23% of surgeons found total arterial revascularization important. Most surgeons (64%) preferred pedicled mammary arteries. Twenty-six percent of surgeons considered sequential grafting to be important.
CONCLUSIONS
Low uptake of total arterial revascularization and bilateral internal mammary artery among the UK consultants may be due to the lack of high-quality evidence demonstrating a significant benefit. It is also possible that reluctance to use certain conduits may stem from low levels of exposure to conduits or inadequate training, particularly given the importance of consultant experience on decision-making
Xpert MTB/RIF Assay Shows Faster Clearance of Mycobacterium tuberculosis DNA with Higher Levels of Rifapentine Exposure.
The Xpert MTB/RIF assay is both sensitive and specific as a diagnostic test. Xpert also reports quantitative output in cycle threshold (CT) values, which may provide a dynamic measure of sputum bacillary burden when used longitudinally. We evaluated the relationship between Xpert CT trajectory and drug exposure during tuberculosis (TB) treatment to assess the potential utility of Xpert CT for treatment monitoring. We obtained serial sputum samples from patients with smear-positive pulmonary TB who were consecutively enrolled at 10 international clinical trial sites participating in study 29X, a CDC-sponsored Tuberculosis Trials Consortium study evaluating the tolerability, safety, and antimicrobial activity of rifapentine at daily doses of up to 20 mg/kg of body weight. Xpert was performed at weeks 0, 2, 4, 6, 8, and 12. Longitudinal CT data were modeled using a nonlinear mixed effects model in relation to rifapentine exposure (area under the concentration-time curve [AUC]). The rate of change of CT was higher in subjects receiving rifapentine than in subjects receiving standard-dose rifampin. Moreover, rifapentine exposure, but not assigned dose, was significantly associated with rate of change in CT (P = 0.02). The estimated increase in CT slope for every additional 100 μg · h/ml of rifapentine drug exposure (as measured by AUC) was 0.11 CT/week (95% confidence interval [CI], 0.05 to 0.17). Increasing rifapentine exposure is associated with a higher rate of change of Xpert CT, indicating faster clearance of Mycobacterium tuberculosis DNA. These data suggest that the quantitative outputs of the Xpert MTB/RIF assay may be useful as a dynamic measure of TB treatment response
The determinants of election to the United Nations Security Council
This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s11127-013-0096-4.The United Nations Security Council (UNSC) is the foremost international body responsible for the maintenance of international peace and security. Members vote on issues of global importance and consequently receive perks—election to the UNSC predicts, for instance, World Bank and IMF loans. But who gets elected to the UNSC? Addressing this question empirically is not straightforward as it requires a model that allows for discrete choices at the regional and international levels; the former nominates candidates while the latter ratifies them. Using an original multiple discrete choice model to analyze a dataset of 180 elections from 1970 to 2005, we find that UNSC election appears to derive from a compromise between the demands of populous countries to win election more frequently and a norm of giving each country its turn. We also find evidence that richer countries from the developing world win election more often, while involvement in warfare lowers election probability. By contrast, development aid does not predict election
Engineering of quantum dot photon sources via electro-elastic fields
The possibility to generate and manipulate non-classical light using the
tools of mature semiconductor technology carries great promise for the
implementation of quantum communication science. This is indeed one of the main
driving forces behind ongoing research on the study of semiconductor quantum
dots. Often referred to as artificial atoms, quantum dots can generate single
and entangled photons on demand and, unlike their natural counterpart, can be
easily integrated into well-established optoelectronic devices. However, the
inherent random nature of the quantum dot growth processes results in a lack of
control of their emission properties. This represents a major roadblock towards
the exploitation of these quantum emitters in the foreseen applications. This
chapter describes a novel class of quantum dot devices that uses the combined
action of strain and electric fields to reshape the emission properties of
single quantum dots. The resulting electro-elastic fields allow for control of
emission and binding energies, charge states, and energy level splittings and
are suitable to correct for the quantum dot structural asymmetries that usually
prevent these semiconductor nanostructures from emitting polarization-entangled
photons. Key experiments in this field are presented and future directions are
discussed.Comment: to appear as a book chapter in a compilation "Engineering the
Atom-Photon Interaction" published by Springer in 2015, edited by A.
Predojevic and M. W. Mitchel
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