829 research outputs found
A Model-Driven Method for the Systematic Literature Review of Qualitative Empirical Research
This paper explores a new model-driven method for systematic literature reviews (SLRs), for use where the empirical studies found in the literature search are based on qualitative research. SLRs are an important component of the evidence-based practice (EBP) paradigm, which is receiving increasing attention in information systems (IS) but has not yet been widely-adopted. We illustrate the model-driven approach to SLRs via an example focused on the use of BPMN (Business Process Modelling Notation) in organizations. We discuss in detail the process followed in using the model-driven SLR method, and show how it is based on a hermeneutic cycle of reading and interpreting, in order to develop and
refine a model which synthesizes the research findings of qualitative studies. This study can serve as an exemplar for other researchers wishing to carry out model-driven SLRs. We conclude with our reflections on the method and some suggestions for further research
The overlap operator as a continued fraction
We use a continued fraction expansion of the sign-function in order to obtain
a five dimensional formulation of the overlap lattice Dirac operator. Within
this formulation the inverse of the overlap operator can be calculated by a
single Krylov space method where nested conjugate gradient procedures are
avoided. We show that the five dimensional linear system can be made well
conditioned using equivalence transformations on the continued fractions. This
is of significant importance when dynamical overlap fermions are simulated.Comment: 3 pages, 1 figure, talk presented by U. Wenger at Lattice2001(chiral
Geology of Exeter and its environs
A 225 km² area around Exeter, described in this report, extends from the villages of Brampford Speke and Whimple in the north to Aylesbeare, Exminster and Woodbury in the south. It is underlain by Carboniferous, Permian, and Triassic solid formations and by a variety of Quaternary superficial deposits. The Namurian Crackington Formation comprises mainly tightly folded shales with subordinate sandstone interbeds. The Permian rocks consist of a lower, predominantly: breccia, sequence (Whipton Formation, Teignmouth Breccia, Monkerton Member) that thins and disappears northwards against a possibly fault-controlled ridge of Crackington Formation; the breccias are overlain by sandstones and mudstones (Dawlish Sandstone and Aylesbeare Mudstone). Volcanic rocks occur at the base of
the Permian sequence and possibly within the Dawlish Sandstone. The latter splits into five alternating sandstone and mudstone members when traced northwards from
Exeter into the Crediton Trough (an area of thick Permian sediments). The Aylesbeare Mudstone is divisible south of Aylesbeare into two members, the lower containing
impersistent sandstones. It is overlain by the basal Triassic gravels (Budleigh Salterton Pebble Beds) which are in turn succeeded by the Otter Sandstone
The pharmacokinetics of medetomidine administered subcutaneously during Isoflurane anaesthesia in Sprague-Dawley rats
Anaesthetic protocols involving the combined use of a sedative agent, medetomidine, and an anaesthetic agent, isoflurane, are increasingly being used in functional magnetic resonance imaging (fMRI) studies of the rodent brain. Despite the popularity of this combination, a standardised protocol for the combined use of medetomidine and isoflurane has not been established, resulting in inconsistencies in the reported use of these drugs. This study investigated the pharmacokinetic detail required to standardise the use of medetomidine and isoflurane in rat brain fMRI studies. Using mass spectrometry, serum concentrations of medetomidine were determined in Sprague-Dawley rats during medetomidine and isoflurane anaesthesia. The serum concentration of medetomidine for administration with 0.5% (vapouriser setting) isoflurane was found to be 14.4 ng/mL (±3.0 ng/mL). The data suggests that a steady state serum concentration of medetomidine when administered with 0.5% (vapouriser setting) isoflurane can be achieved with an initial subcutaneous (SC) dose of 0.12 mg/kg of medetomidine followed by a 0.08 mg/kg/h SC infusion of medetomidine. Consideration of these results for future studies will facilitate standardisation of medetomidine and isoflurane anaesthetic protocols during fMRI data acquisition
Mass Dependent Evolution and the Light Gluino Existence
There is an intriguing discrepancy between \alpha_s(M_Z) values measured
directly at the CERN -factory and low-energy (at few GeV) measurements
transformed to by a massless QCD \alpha_s(Q) evolution relation.
There exists an attempt to reconcile this discrepancy by introducing a light
gluino \gl in the MSSM.
We study in detail the influence of heavy thresholds on \alpha_s(Q)
evolution. First, we consruct the "exact" explicit solution to the
mass-dependent two-loop RG equation for the running \alpha_s(Q). This solution
describes heavy thresholds smoothly. Second, we use this solution to
recalculate anew \alpha_s(M_Z) values corresponding to "low-energy" input data.
Our analysis demonstrates that using {\it mass-dependent RG procedure}
generally produces corrections of two types: Asymptotic correction due to
effective shift of threshold position; Local threshold correction only for the
case when input experiment lies in the close vicinity of heavy particle
threshold: .
Both effects result in the effective shift of the \asmz values of the order
of . However, the second one could be enhanced when the gluino mass is
close to a heavy quark mass. For such a case the sum effect could be important
for the discussion of the light gluino existence as it further changes the
\gl mass.Comment: 13, Late
Random close packing of granular matter
We propose an interpretation of the random close packing of granular
materials as a phase transition, and discuss the possibility of experimental
verification.Comment: 6 page
Cluster Spin Glass Distribution Functions in LaSrCuO
Signatures of the cluster spin glass have been found in a variety of
experiments, with an effective onset temperature that is frequency
dependent. We reanalyze the experimental results and find that they are
characterized by a distribution of activation energies, with a nonzero glass
transition temperature . While the distribution of activation
energies is the same, the distribution of weights depends on the process.
Remarkably, the weights are essentially doping independent.Comment: 5 pages, 5 ps figure
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