14,221 research outputs found
Cardiovascular morbidity and mortality after kidney transplantation
Kidney transplantation is the optimal treatment for patients with end stage renal disease (ESRD) who would otherwise require dialysis. Patients with ESRD are at dramatically increased cardiovascular (CV) risk compared to the general population. As well as improving quality of life, successful transplantation accords major benefits by reducing cardiovascular risk in these patients. Worldwide, cardiovascular disease remains the leading cause of death with a functioning graft and therefore is a leading cause of graft failure. This review focuses on the mechanisms underpinning excess cardiovascular morbidity and mortality and current evidence for improving cardiovascular risk in kidney transplant recipients. Conventional cardiovascular risk factors such as hypertension, diabetes mellitus, dyslipidaemia, and pre-existing ischaemic heart disease are all highly prevalent in this group. In addition, kidney transplant recipients exhibit a number of risk factors associated with pre-existing renal disease. Furthermore, complications specific to transplantation may ensue includingreduced graft function, side effects of immunosuppression and post transplantation diabetes mellitus. Strategies to improve cardiovascular
outcomes post transplantation may include pharmacological intervention including lipid lowering or antihypertensive therapy, optimisation of graft function, lifestyle intervention and personalising immunosuppression to the
individual patients risk profile
On the Size-Dependence of the Inclination Distribution of the Main Kuiper Belt
We present a new analysis of the currently available orbital elements for the
known Kuiper belt objects. In the non-resonant, main Kuiper belt we find a
statistically significant relationship between an object's absolute magnitude
(H) and its inclination (i). Objects with H~170 km for a 4%
albedo) have higher inclinations than those with H>6.5 (radii >~ 170 km). We
have shown that this relationship is not caused by any obvious observational
bias. We argue that the main Kuiper belt consists of the superposition of two
distinct distributions. One is dynamically hot with inclinations as large as
\~35 deg and absolute magnitudes as bright as 4.5; the other is dynamically
cold with i6.5. The dynamically cold population is most likely
dynamically primordial. We speculate on the potential causes of this
relationship.Comment: 14 pages, 6 postscript figure
Isolating Excited States of the Nucleon in Lattice QCD
We discuss a robust projection method for the extraction of excited-state
masses of the nucleon from a matrix of correlation functions. To illustrate the
algorithm in practice, we present results for the positive parity excited
states of the nucleon in quenched QCD. Using eigenvectors obtained via the
variational method, we construct an eigenstate-projected correlation function
amenable to standard analysis techniques. The method displays its utility when
comparing results from the fit of the projected correlation function with those
obtained from the eigenvalues of the variational method. Standard nucleon
interpolators are considered, with and correlation
matrix analyses presented using various combinations of source-smeared,
sink-smeared and smeared-smeared correlation functions. Using these new robust
methods, we observe a systematic dependency of the nucleon excited-state masses
on source- and sink-smearing levels. To the best of our knowledge, this is the
first clear indication that a correlation matrix of standard nucleon
interpolators is insufficient to isolate the eigenstates of QCD.Comment: May 2009.13pp, Minor changes and references adde
Low-lying positive-parity excited states of the nucleon
We present an overview of the correlation-matrix methods developed recently
by the CSSM Lattice Collaboration for the isolation of excited states of the
nucleon. Of particular interest is the first positive-parity excited-state of
the nucleon known as the Roper resonance. Using eigenvectors of the correlation
matrix we construct parity and eigenstate projected correlation functions which
are analysed using standardized methods. The robust nature of this approach for
extracting the eigenstate energies is presented. We report the importance of
using a variety of source and sink smearings in achieving this. Ultimately the
independence of the eigenstate energies from the interpolator basis is
demonstrated. In particular we consider correlation matrices built
from a variety of interpolators and smearing levels. Using FLIC fermions to
access the light quark mass regime, we explore the curvature encountered in the
energy of the states as the chiral limit is approached. We report a low-lying
Roper state contrasting earlier results using correlation matrices. To the best
of our knowledge, this is the first time a low-lying Roper resonance has been
found using correlation matrix methods. Finally, we present our results in the
context of the Roper results reported by other groups.Comment: 8 pages, 4 figures., Presented at the XXVII International Symposium
on Lattice Field Theory, July 26-31, 2009, Peking University, Beijing, Chin
Upper limits on gravitational-wave signals based on loudest events
Searches for gravitational-wave bursts have often focused on the loudest
event(s) in searching for detections and in determining upper limits on
astrophysical populations. Typical upper limits have been reported on event
rates and event amplitudes which can then be translated into constraints on
astrophysical populations. We describe the mathematical construction of such
upper limits.Comment: 8 pages, 1 figur
A Pharmacological and Toxicological Profile of Silver as an Antimicrobial Agent in Medical Devices
Silver is used widely in wound dressings and medical devices as a broad-spectrum antibiotic. Metallic silver and most inorganic silver compounds ionise in moisture, body fluids, and secretions to release biologically active Ag+. The ion is absorbed into the systemic circulation from the diet and drinking water, by inhalation and through intraparenteral administration. Percutaneous absorption of Ag+ through intact or damaged skin is low. Ag+ binds strongly to metallothionein, albumins, and macroglobulins and is metabolised to all tissues other than the brain and the central nervous system. Silver sulphide or silver selenide precipitates, bound lysosomally in soft tissues, are inert and not associated with an irreversible toxic change. Argyria and argyrosis are the principle effects associated with heavy deposition of insoluble silver precipitates in the dermis and cornea/conjunctiva. Whilst these changes may be profoundly disfiguring and persistent, they are not associated with pathological damage in any tissue. The present paper discusses the mechanisms of absorption and metabolism of silver in the human body, presumed mechanisms of argyria and argyrosis, and the elimination of silver-protein complexes in the bile and urine. Minimum blood silver levels consistent with early signs of argyria or argyrosis are not known. Silver allergy does occur but the extent of the problem is not known. Reference values for silver exposure are discussed
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