20,306 research outputs found
Clinical outcome research at the University of Westminster Polyclinic
Research into naturopathic treatments is problematic if
confined to double blind randomised trials. This paper discusses how an outcome measure was adapted and used to measure the patients' perception of effectiveness of treatment at the University of Westminster Polyclinic
Writing in your own voice: An intervention that reduces plagiarism and common writing problems in students' scientific writing.
In many of our courses, particularly laboratory courses, students are expected to engage in scientific writing. Despite various efforts by other courses and library resources, as instructors we are often faced with the frustration of student plagiarism and related writing problems. Here, we describe a simple Writing in Your Own Voice intervention designed to help students become more aware of different types of plagiarism and writing problems, avoid those problems, and practice writing in their own voice. In this article, we will introduce the types of plagiarism and writing problems commonly encountered in our molecular biology laboratory course, the intervention, and the results of our study. From the evaluation of 365 student reports, we found the intervention resulted in nearly 50% fewer instances of plagiarism and common writing problems. We also observed significantly fewer instances of severe plagiarism (e.g. several sentences copied from an external source). In addition, we find that the effects last for several weeks after the students complete the intervention assignment. This assignment is particularly easy to implement and can be a very useful tool for teaching students how to write in their own voices. © 2019 International Union of Biochemistry and Molecular Biology, 47(5):589-598, 2019
Non-linear enhancement of laser generated ultrasonic Rayleigh waves by cracks
Laser generated ultrasound has been widely used for detecting cracks, surface and sub-surface defects in
many different materials. It provides a non-contact wideband excitation source which can be focused into
different geometries. Previous workers have reported enhancement of the laser generated Rayleigh wave
when a crack is illuminated by pulsed laser beam irradiation. We demonstrate that the enhancement
observed is due to a combination of source truncation, the free boundary condition at the edge of the crack
and interference effects. Generating a Rayleigh wave over a crack can lead to enhancement of the
amplitude of the Rayleigh wave signal, a shift in the dominant frequency of the wideband Rayleigh wave
and strong enhancement of the high frequency components of the Rayleigh wave
Solution of the dispersionless Hirota equations
The dispersionless differential Fay identity is shown to be equivalent to a
kernel expansion providing a universal algebraic characterization and solution
of the dispersionless Hirota equations. Some calculations based on D-bar data
of the action are also indicated.Comment: Late
A study of the application of singular perturbation theory
A hierarchical real time algorithm for optimal three dimensional control of aircraft is described. Systematic methods are developed for real time computation of nonlinear feedback controls by means of singular perturbation theory. The results are applied to a six state, three control variable, point mass model of an F-4 aircraft. Nonlinear feedback laws are presented for computing the optimal control of throttle, bank angle, and angle of attack. Real Time capability is assessed on a TI 9900 microcomputer. The breakdown of the singular perturbation approximation near the terminal point is examined Continuation methods are examined to obtain exact optimal trajectories starting from the singular perturbation solutions
Fine Tuning Free Paradigm of Two Measures Theory: K-Essence, Absence of Initial Singularity of the Curvature and Inflation with Graceful Exit to Zero Cosmological Constant State
The dilaton-gravity sector of the Two Measures Field Theory (TMT)is explored
in detail in the context of cosmology. The model possesses scale invariance
which is spontaneously broken due to the intrinsic features of the TMT
dynamics. The effective model represents an explicit example of the effective
k-essence resulting from first principles without any exotic term in the
fundamental action. Depending of the choice of regions in the parameter space,
TMT exhibits different possible outputs for cosmological dynamics: a) Absence
of initial singularity of the curvature while its time derivative is singular.
This is a sort of "sudden" singularities studied by Barrow on purely kinematic
grounds. b) Power law inflation in the subsequent stage of evolution. Depending
on the region in the parameter space (but without fine tuning) the inflation
ends with a graceful exit either into the state with zero cosmological constant
(CC) or into the state driven by both a small CC and the field phi with a
quintessence-like potential. c) Possibility of resolution of the old CC
problem. From the point of view of TMT, it becomes clear why the old CC problem
cannot be solved (without fine tuning) in conventional field theories. d) TMT
enables two ways for achieving small CC without fine tuning of dimensionfull
parameters: either by a seesaw type mechanism or due to a correspondence
principle between TMT and conventional field theories (i.e theories with only
the measure of integration sqrt{-g} in the action. e) There is a wide range of
the parameters such that in the late time universe: the equation-of-state
w=p/\rho <-1; w asymptotically (as t\to\infty) approaches -1 from below; \rho
approaches a constant, the smallness of which does not require fine tuning of
dimensionfull parameters.Comment: 37 pages, 20 figures. Minor misprints corrected, reference added. The
final version published in Phys. Rev.
AdS/CFT Energy Loss in Time-Dependent String Configurations
We analyze spacetime momentum currents on a classical string worldsheet,
study their generic connection via AdS/CFT correspondence to the instantaneous
energy loss of the dual field theory degrees of freedom and suggest a general
formula for computing energy loss in a time-dependent string configuration.
Applying this formula to the case of falling strings, generally dual to light
quarks, reveals that the energy loss does not display a well-pronounced Bragg
peak at late times, as previously believed. Finally, we comment on the possible
implications of this result to the jet quenching phenomena in heavy ion
collisions.Comment: 8 pages, 1 figure. Issues with sign conventions resolved and other
minor corrections. Discussion and references added. Published versio
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