19,203 research outputs found
An exploratory survey of current practice in the medical device industry
This article is (c) Emerald Group Publishing and permission has been granted for this version to appear here. Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited.Purpose – This study seeks to examine the extent to which mainstream tools and strategies are applied in the medical devices sector, which is highly fragmented and contains a high percentage of small companies, and to determine if company size impacts on manufacturing strategy selection.
Design/methodology/approach – A questionnaire was developed and disseminated through a number of channels. Responses were received from 38 companies in the UK and Ireland, describing 68 products taken to market in the past five years.
Findings – Because of the limited scope of the survey, the findings are indicative rather than conclusive, and interesting trends have emerged. New to the world products were much more likely to exceed company expectations of market success compared to derivative products. It was found that the majority of these innovative products were developed by small companies. Large companies appear to favour minor upgrades over major upgrades even though these prove – on the data presented – to be less successful overall.
Practical implications – These results provide those engaged in this sector with comparative information and some insights for further improvement. The reported trends with respect to company size and product complexity (or degree of novelty) are particularly illuminating. Academically, this sets some expected trends on a firmer footing and unearths one or two unexpected findings.
Originality/value – It is believed that this is the largest survey of determinants of success in UK medical device companies and it provides a comparison with other sectors
Maxillary nerve blocks in horses: an experimental comparison of surface landmark and ultrasound-guided techniques
A Color Dual Form for Gauge-Theory Amplitudes
Recently a duality between color and kinematics has been proposed, exposing a
new unexpected structure in gauge theory and gravity scattering amplitudes.
Here we propose that the relation goes deeper, allowing us to reorganize
amplitudes into a form reminiscent of the standard color decomposition in terms
of traces over generators, but with the role of color and kinematics swapped.
By imposing additional conditions similar to Kleiss-Kuijf relations between
partial amplitudes, the relationship between the earlier form satisfying the
duality and the current one is invertible. We comment on extensions to loop
level.Comment: 5 pages, 4 figure
Dual Labour Markets and Menu Costs: Explaining the Cyclicality of Productivity and Wage Differentials
The conventional menu cost framework performs poorly with realistic labour supply elasticities; the menu costs required for price rigidity are very high and the welfare consequences of monetary disturbances are negligible. We show that the presence of dual labour markets greatly improves the performance of the framework both by reducing menu cost requirements and by boosting the welfare consequences. In addition, the introduction of dual labour markets provides an explanation of procyclical productivity and the shrinking of wage differentials during booms, in line with stylized facts on business cycles.
Immunofluorescent Examination of Biopsies from Long-Term Renal Allografts
Immunofluorescent examination of open renal biopsies revealed clear-cut glomerular localization of immunoglobulins not related clearly to the quality of donor-recipient histocompatibility in 19 of 34 renal allografts. The biopsies were obtained 18 to 31 months after transplantations primarily from related donors with a variable quality of histocompatibility match. IgG was the predominant immunoglobulin class fixed in 13 biopsies, and IgM in six. The pattern of immunoglobulin deposition was linear, connoting anti-GBM antibody in four of the 19; it was granular and discontinuous, connoting antigen–antibodycomplex deposits, in 13. An immune process may affect glomeruli of renal allografts by mechanisms comparable to those that cause glomerulonephritis in native kidneys. The transplant glomerulonephritis may represent a persistence of the same disease that originally destroyed the host kidneys or the consequence of a new humoral antibody response to allograft antigens. © 1970, Massachusetts Medical Society. All rights reserved
On Lorentz invariance and supersymmetry of four particle scattering amplitudes in orbifold sigma model
The supersymmetric orbifold sigma model is expected to describe the
IR limit of the Matrix string theory. In the framework of the model the type
IIA string interaction is governed by a vertex which was recently proposed by
R.Dijkgraaf, E.Verlinde and H.Verlinde. By using this interaction vertex we
derive all four particle scattering amplitudes directly from the orbifold model
in the large limit.Comment: Latex, 23 page
EXPERIMENTAL PIG-TO-PIG TRANSMISSION DYNAMICS FOR AFRICAN SWINE FEVER VIRUS, GEORGIA 2007/1 STRAIN- CORRIGENDUM
Self-forces on extended bodies in electrodynamics
In this paper, we study the bulk motion of a classical extended charge in
flat spacetime. A formalism developed by W. G. Dixon is used to determine how
the details of such a particle's internal structure influence its equations of
motion. We place essentially no restrictions (other than boundedness) on the
shape of the charge, and allow for inhomogeneity, internal currents,
elasticity, and spin. Even if the angular momentum remains small, many such
systems are found to be affected by large self-interaction effects beyond the
standard Lorentz-Dirac force. These are particularly significant if the
particle's charge density fails to be much greater than its 3-current density
(or vice versa) in the center-of-mass frame. Additional terms also arise in the
equations of motion if the dipole moment is too large, and when the
`center-of-electromagnetic mass' is far from the `center-of-bare mass' (roughly
speaking). These conditions are often quite restrictive. General equations of
motion were also derived under the assumption that the particle can only
interact with the radiative component of its self-field. These are much simpler
than the equations derived using the full retarded self-field; as are the
conditions required to recover the Lorentz-Dirac equation.Comment: 30 pages; significantly improved presentation; accepted for
publication in Phys. Rev.
Signature of chaos in gravitational waves from a spinning particle
A spinning test particle around a Schwarzschild black hole shows a chaotic
behavior, if its spin is larger than a critical value. We discuss whether or
not some peculiar signature of chaos appears in the gravitational waves emitted
from such a system. Calculating the emitted gravitational waves by use of the
quadrupole formula, we find that the energy emission rate of gravitational
waves for a chaotic orbit is about 10 times larger than that for a circular
orbit, but the same enhancement is also obtained by a regular "elliptic" orbit.
A chaotic motion is not always enhance the energy emission rate maximally. As
for the energy spectra of the gravitational waves, we find some characteristic
feature for a chaotic orbit. It may tell us how to find out a chaotic behavior
of the system. Such a peculiar behavior, if it will be found, may also provide
us some additional informations to determine parameters of a system such as a
spin.Comment: 14 pages, LaTeX, to appear in Phys. Rev.
Microbial ecology of Thiobacillus ferrooxidans
FINAL TECHNICAL REPORT
TO
U.S. DEPARTMENT OF THE INTERIOR
Geological Survey
Washington. D.C.The contents of this report were developed in part under a grant from
the Department of the Interior, U.S. Geological Survey. Grant number 14-08-0001-61313
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