1,286 research outputs found
Enhancing the scoping study methodology: a large, inter-professional teamâs experience with Arksey and OâMalleyâs framework
Background: Scoping studies are increasingly common for broadly searching the literature on a specific topic, yet researchers lack an agreed-upon definition of and framework for the methodology. In 2005, Arksey and O'Malley offered a methodological framework for conducting scoping studies. In their subsequent work, Levac et al. responded to Arksey and O'Malley's call for advances to their framework. Our paper builds on this collective work to further enhance the methodology. Discussion: This paper begins with a background on what constitutes a scoping study, followed by a discussion about four primary subjects: (1) the types of questions for which Arksey and O'Malley's framework is most appropriate, (2) a contribution to the discussion aimed at enhancing the six steps of Arskey and O'Malley's framework, (3) the strengths and challenges of our experience working with Arksey and O'Malley's framework as a large, inter-professional team, and (4) lessons learned. Our goal in this paper is to add to the discussion encouraged by Arksey and O'Malley to further enhance this methodology. Summary: Performing a scoping study using Arksey and O'Malley's framework was a valuable process for our research team even if how it was useful was unexpected. Based on our experience, we recommend researchers be aware of their expectations for how Arksey and O'Malley's framework might be useful in relation to their research question, and remain flexible to clarify concepts and to revise the research question as the team becomes familiar with the literature. Questions portraying comparisons such as between interventions, programs, or approaches seem to be the most suitable to scoping studies. We also suggest assessing the quality of studies and conducting a trial of the method before fully embarking on the charting process in order to ensure consistency. The benefits of engaging a large, inter-professional team such as ours throughout every stage of Arksey and O'Malley's framework far exceed the challenges and we recommend researchers consider the value of such a team. The strengths include breadth and depth of knowledge each team member brings to the study and time efficiencies. In our experience, the most significant challenges presented to our team were those related to consensus and resource limitations. Effective communication is key to the success of a large group. We propose that by clarifying the framework, the purposes of scoping studies are attainable and the definition is enriched
The role of aerodynamic forces in a mathematical model for suspension bridges
In a fish-bone model for suspension bridges studied by us in a previous paper
we introduce linear aerodynamic forces. We numerically analyze the role of
these forces and we theoretically show that they do not influence the onset of
torsional oscillations. This suggests a new explanation for the origin of
instability in suspension bridges: it is a combined interaction between
structural nonlinearity and aerodynamics and it follows a precise pattern. This
gives an answer to a long-standing question about the origin of torsional
instability in suspension bridges
A nonlinear hydrodynamical approach to granular materials
We propose a nonlinear hydrodynamical model of granular materials. We show
how this model describes the formation of a sand pile from a homogeneous
distribution of material under gravity, and then discuss a simulation of a
rotating sandpile which shows, in qualitative agreement with experiment, a
static and dynamic angle of repose.Comment: 17 pages, 14 figures, RevTeX4; minor changes to wording and some
additional discussion. Accepted by Phys. Rev.
Diagnosis of childhood tuberculosis and host RNA expression in Africa
Improved diagnostic tests for tuberculosis in children are needed. We hypothesized that transcriptional signatures of host blood could be used to distinguish tuberculosis from other diseases in African children who either were or were not infected with the human immunodeficiency virus (HIV
Continuous Quantum Measurement and the Quantum to Classical Transition
While ultimately they are described by quantum mechanics, macroscopic
mechanical systems are nevertheless observed to follow the trajectories
predicted by classical mechanics. Hence, in the regime defining macroscopic
physics, the trajectories of the correct classical motion must emerge from
quantum mechanics, a process referred to as the quantum to classical
transition. Extending previous work [Bhattacharya, Habib, and Jacobs, Phys.
Rev. Lett. {\bf 85}, 4852 (2000)], here we elucidate this transition in some
detail, showing that once the measurement processes which affect all
macroscopic systems are taken into account, quantum mechanics indeed predicts
the emergence of classical motion. We derive inequalities that describe the
parameter regime in which classical motion is obtained, and provide numerical
examples. We also demonstrate two further important properties of the classical
limit. First, that multiple observers all agree on the motion of an object, and
second, that classical statistical inference may be used to correctly track the
classical motion.Comment: 12 pages, 4 figures, Revtex
Governing culture: legislators, interpreters and accountants
Cultural policy has become dominated by questions of how to account for the intangible value of government investments. This is as a result of longstanding developments within governmentâs approaches to policy making, most notably those influenced by practices of audit and accounting. This paper will outline these developments with reference to Peter Millerâs concept of calculative practices, and will argue two central points: first, that there are practical solutions to the problem of measuring the value of culture that connect central government discourses with the discourses of the cultural sector; and second, the paper will demonstrate how academic work has been central to this area of policy making. As a result of the centrality of accounting academics in cultural policy, for example in providing advice on the appropriate measurement tools and techniques, questions are raised about the role academia might take vis-Ă -vis public policy. Accounting professionals and academics not only provide technical expertise that informs state calculative practices, but also play a surveillance role through the audit and evaluation of government programmes, and act as interpreters in defining terms of performance measurement, success and failure. The paper therefore concludes by reflecting on recent work by Phillip Schlesinger to preserve academic integrity whilst allowing accounting scholars and academics influence and partnership in policy
First principles study of point defects in titanium oxycarbide
We have performed first principles density functional theory calculations to study the formation energy of point defects
in TiC, TiO and TiCO compounds. The formation energy of isolated vacancies were obtained for different equilibrium
conditions. For binary compounds, we have also calculated the formation energy of antisite defects. It was found that
the defect formation energies strongly depend on the chemical environment. Our results show that C vacancies are
easily formed in TiC and TiCO. For the TiO compound, Ti vacancies are highly probable to occur and O vacancies
are also easily formed under titanium rich atmosphere.Fundação para a CiĂȘncia e a Tecnologia (FCT) â Programa Operacional âCiĂȘncia , Tecnologia, Inovaçãoâ â CONC-REEQ/443/EEI/2005, POCTI/CTM/69362/200
Micro to nanostructural observations in neutron irradiated nuclear graphites PCEA and PCIB
The neutron irradiation-induced structural changes in nuclear grade graphites PCEA and PCIB were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED) and electron energy loss spectroscopy (EELS). The graphite samples were irradiated at the Advanced Test Reactor at the Idaho National Laboratory. Received doses ranged from 1.5 to 6.8 displacements per atom and irradiation temperatures varied between 350 °C and 670 °C. XRD and Raman measurements provided evidence for irradiation induced crystallite fragmentation, with crystallite sizes reduced by 39â55%. Analysis of TEM images was used to quantify fringe length, tortuosity, and relative misorientation of planes, and indicated that neutron irradiation induced basal plane fragmentation and curvature. EELS was used to quantify the proportion of sp2 bonding and specimen density; a slight reduction in planar-sp2 content (due to the buckling basal planes and the introduction of non-six-membered rings) agreed with the observations from TEM
Measurement of and charged current inclusive cross sections and their ratio with the T2K off-axis near detector
We report a measurement of cross section and the first measurements of the cross section
and their ratio
at (anti-)neutrino energies below 1.5
GeV. We determine the single momentum bin cross section measurements, averaged
over the T2K -flux, for the detector target material (mainly
Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory
frame kinematics of 500 MeV/c. The
results are and $\sigma(\nu)=\left( 2.41\
\pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}^{2}R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)=
0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure
Differential regulation of amidase- and formamidase-mediated ammonia production by the Helicobacter pylori fur repressor.
The production of high levels of ammonia allows the human gastric pathogen
Helicobacter pylori to survive the acidic conditions in the human stomach.
H. pylori produces ammonia through urease-mediated degradation of urea,
but it is also able to convert a range of amide substrates into ammonia
via its AmiE amidase and AmiF formamidase enzymes. Here data are provided
that demonstrate that the iron-responsive regulatory protein Fur directly
and indirectly regulates the activity of the two H. pylori amidases. In
contrast to other amidase-positive bacteria, amidase and formamidase
enzyme activities were not induced by medium supplementation with their
respective substrates, acrylamide and formamide. AmiE protein expression
and amidase enzyme activity were iron-repressed in H. pylori 26695 but
constitutive in the isogenic fur mutant. This regulation was mediated at
the transcriptional level via the binding of Fur to the amiE promoter
region. In contrast, formamidase enzyme activity was not iron-repressed
but was significantly higher in the fur mutant. This effect was not
mediated at the transcriptional level, and Fur did not bind to the amiF
promoter region. These roles of Fur in regulation of the H. pylori
amidases suggest that the H. pylori Fur regulator may have acquired extra
functions to compensate for the absence of other regulatory systems
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