331 research outputs found
Standardized image interpretation and post-processing in cardiovascular magnetic resonance - 2020 update : Society for Cardiovascular Magnetic Resonance (SCMR): Board of Trustees Task Force on Standardized Post-Processing
With mounting data on its accuracy and prognostic value, cardiovascular magnetic resonance (CMR) is becoming an increasingly important diagnostic tool with growing utility in clinical routine. Given its versatility and wide range of quantitative parameters, however, agreement on specific standards for the interpretation and post-processing of CMR studies is required to ensure consistent quality and reproducibility of CMR reports. This document addresses this need by providing consensus recommendations developed by the Task Force for Post-Processing of the Society for Cardiovascular Magnetic Resonance (SCMR). The aim of the Task Force is to recommend requirements and standards for image interpretation and post-processing enabling qualitative and quantitative evaluation of CMR images. Furthermore, pitfalls of CMR image analysis are discussed where appropriate. It is an update of the original recommendations published 2013
The pathology of chronic Drechslera campanulata toxicosis in inbred rats
Cultures on autoclaved maize of the phytopathogenic fungus, Drechslera campanulata, were incorporated into diets and fed to male inbred BDIX rats. In a pilot trial, a diet containing 30% D. campanulata culture material killed 5 out of 5 rats in 15-25 days. Lesions included gastric corpus erosions, gastrorrhagia and ulcerative typhlitis. Diets containing 5 % or 10 % culture material induced erosive to ulcerative typhlitis and oedema and hyperplasia of the ileocaecal lymph nodes in 40 out of 40 rats. Other changes included: mass loss; normocytic, hyperchromic anaemia; leukocytosis with neutrophilia; reductions in plasma proteins, creatinine, calcium and cholesterol; elevated serum enzymes; hepatosis, nephrosis and mycoplasma-like interstitial pneumoma. No lesions were present in control rats, and their profiles were normal. Ulcerative typhlitis induced by D. campanulata in rats resembles that seen in chronic piperonyl butoxide intoxication as well as that due to single treatments of indomethacid, although small intestinal ulcers are more frequent in the latter. Overgrowth of intestinal flora may be involved in ulcer pathogenesis. The pathology of drechsleratoxicosis in rats is compared to that in sheep and goats where necrotic lesions in the forestomach and, to a lesser extent, in the caecum are characteristic findings.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201
Bandlimited approximations to the truncated Gaussian and applications
In this paper we extend the theory of optimal approximations of functions in the -metric by entire functions of prescribed
exponential type (bandlimited functions). We solve this problem for the
truncated and the odd Gaussians using explicit integral representations and
fine properties of truncated theta functions obtained via the maximum principle
for the heat operator. As applications, we recover most of the previously known
examples in the literature and further extend the class of truncated and odd
functions for which this extremal problem can be solved, by integration on the
free parameter and the use of tempered distribution arguments. This is the
counterpart of the work \cite{CLV}, where the case of even functions is
treated.Comment: to appear in Const. Appro
An experimental mycotoxicosis in sheep and goats caused by Drechslera campanulata, a fungal pathogen of green oats
Field outbreaks of a syndrome of unknown aetiology associated with the grazing of green oats (Avena sativa) in the south-western Cape Province were characterized by diarrhoea, photosensitivity and death in goats and by diarrhoea and a reduction in milk production in cows. A phytopathogenic fungus, Drechslera campanulata, was isolated from conspicuous reddish-brown leaf spots on oat plants collected from both outbreaks.
Pure cultures on autoclaved maize of D. campanulata isolates from oat leaves implicated in both field outbreaks, as well as a Canadian isolate, proved to be highly toxic to ducklings, goats and sheep. Characteristic clinical signs of the fatal mycotoxicosis caused by D. campanulata culture material in goats and sheep were anorexia, apathy, diarrhoea and ruminal stasis. Photosensitivity, however, was not induced. Necrosis of the forestomach mucosa was the most characteristic gross pathological change. Histopathological findings included mild focal erosions to severe, diffuse, coagulative necrosis of the mucosa in the rumen, reticulum and omasum and congestion and haemorrhages in the abomasum. These results provide circumstantial evidence that green oat leaves infected by D. campanulata may cause outbreaks of a mycotoxicosis in grazing animals.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format
Z-score mapping for standardized analysis and reporting of cardiovascular magnetic resonance modified Look-Locker inversion recovery (MOLLI) T1 data: normal behavior and validation in patients with amyloidosis
BACKGROUND: T1 mapping using modified Look-Locker inversion recovery (MOLLI) provides quantitative information on myocardial tissue composition. T1 results differ between sites due to variations in hardware and software equipment, limiting the comparability of results. The aim was to test if Z-scores can be used to compare the results of MOLLI T1 mapping from different cardiovascular magnetic resonance (CMR) platforms. METHODS: First, healthy subjects (n = 15) underwent 11 combinations of native short-axis T1 mapping (four CMR systems from two manufacturers at 1.5 T and 3 T, three MOLLI schemes). Mean and standard deviation (SD) of septal myocardial T1 were derived for each combination. T1 maps were transformed into Z-score maps based on mean and SD values using a prototype post-processing module. Second, Z-score mapping was applied to a validation sample of patients with cardiac amyloidosis at 1.5 T (n = 25) or 3 T (n = 13). RESULTS: In conventional T1 analysis, results were confounded by variations in field strength, MOLLI scheme, and manufacturer-specific system characteristics. Z-score-based analysis yielded consistent results without significant differences between any two of the combinations in part 1 of the study. In the validation sample, Z-score mapping differentiated between patients with cardiac amyloidosis and healthy subjects with the same diagnostic accuracy as standard T1 analysis regardless of field strength. CONCLUSIONS: T1 analysis based on Z-score mapping provides consistent results without significant differences due to field strengths, CMR systems, or MOLLI variants, and detects cardiac amyloidosis with the same diagnostic accuracy as conventional T1 analysis. Z-score mapping provides a means to compare native T1 results acquired with MOLLI across different CMR platforms
Guidelines for training in cardiovascular magnetic resonance (CMR)
These "Guidelines for training in Cardiovascular Magnetic Resonance" were developed by the Certification Committee of the Society for Cardiovascular Magnetic Resonance (SCMR) and approved by the SCMR Board of Trustees
Time-Resolved HST Spectroscopy of Four Eclipsing Magnetic Cataclysmic Variables
Time-resolved HST UV eclipse spectrophotometry is presented for the magnetic
CVs V1309 Ori, MN Hya, V2301 Oph, and V1432 Aql. Separation of the light curves
into wavebands allows the multiple emission components to be distinguished.
Photospheric hot spots are detected in V1309 Ori and V2301 Oph. The emission-
line spectra of V1309 Ori and MN Hya are unusual, with the strength of N V 1240
and N IV 1718 suggesting an overabundance of nitrogen. Three epochs of
observation of the asynchronous V1432 Aql cover ~1/3 of a 50-day lap cycle
between the white dwarf spin and binary orbit. The light curves vary from epoch
to epoch and as a function of waveband. The dereddened UV spectrum is extremely
bright and the spectral energy distribution coupled with the duration of
eclipse ingress indicate that the dominant source of energy is a hot
(T~35,000K) white dwarf. Undiminished line emission through eclipse indicates
that the eclipse is caused by the accretion stream, not the secondary star. The
hot white dwarf, combined with its current asynchronous nature and rapid
timescale for relocking, suggests that V1432 Aql underwent a nova eruption in
the past 75-150 yr. The reversed sense of asynchronism, with the primary star
currently spinning up toward synchronism, is not necessarily at odds with this
scenario, if the rotation of the magnetic white dwarf can couple to the ejecta
during the wind phase of the eruption.Comment: To appear in ApJ Part 1; 25 pages, 12 figure
Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering
First measurements of azimuthal asymmetries in hadron-pair production in
deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron)
and NH_3 (proton) targets are presented. The data were taken in the years
2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c
at the CERN SPS. The asymmetries provide access to the transversity
distribution functions, without involving the Collins effect as in single
hadron production. The sizeable asymmetries measured on the NH_ target indicate
non-vanishing u-quark transversity and two-hadron interference fragmentation
functions. The small asymmetries measured on the ^6LiD target can be
interpreted as indication for a cancellation of u- and d-quark transversities.Comment: 13 pages, 4 figures, updated to the published versio
Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs
We present a determination of the gluon polarisation Delta g/g in the
nucleon, based on the longitudinal double-spin asymmetry of DIS events with a
pair of large transverse-momentum hadrons in the final state. The data were
obtained by the COMPASS experiment at CERN using a 160 GeV/c polarised muon
beam scattering off a polarised ^6LiD target. The gluon polarisation is
evaluated by a Neural Network approach for three intervals of the gluon
momentum fraction x_g covering the range 0.04 < x_g < 0.27. The values obtained
at leading order in QCD do not show any significant dependence on x_g. Their
average is Delta g/g = 0.125 +/- 0.060 (stat.) +/- 0.063 (syst.) at x_g=0.09
and a scale of mu^2 = 3 (GeV/c)^2.Comment: 13 pages, 6 figures and 3 table
The Spin-dependent Structure Function of the Proton g_1^p and a Test of the Bjorken Sum Rule
The inclusive double-spin asymmetry, A_1^p, has been measured at COMPASS in
deepinelastic polarised muon scattering off a large polarised NH3 target. The
data, collected in the year 2007, cover the range Q2 > 1 (GeV/c)^2, 0.004 < x <
0.7 and improve the statistical precision of g_1^p(x) by a factor of two in the
region x < 0.02. The new proton asymmetries are combined with those previously
published for the deuteron to extract the non-singlet spin-dependent structure
function g_1^NS(x,Q2). The isovector quark density, Delta_q_3(x,Q2), is
evaluated from a NLO QCD fit of g_1^NS. The first moment of Delta_q3 is in good
agreement with the value predicted by the Bjorken sum rule and corresponds to a
ratio of the axial and vector coupling constants g_A/g_V =
1.28+-0.07(stat)+-0.10(syst).Comment: 12 pages, 5 figure
- …