2,729 research outputs found
Robustness of a cross contamination model describing transfer of pathogens during grinding of meat
Validation of Repeated Endothelial Function Measurements Using EndoPAT in Stroke
BackgroundDecreased endothelial function (EF) may be a prognostic marker for stroke. Measuring pharmacological effects on EF may be of interest in the development of personalized medicine for stroke prevention. In this study, we assessed the reliability of repeated EF measurements using a pulse amplitude tonometry technology in acute stroke patients. Similarly, reliability was tested in healthy subjects devoid of vascular disease to estimate reactivity and reliability in a younger non-stroke population.Materials and methodsEF was assessed using the EndoPAT2000 in 20 healthy volunteers (men 50%, mean age 35.85 ± 3.47 years) and 21 stroke patients (men 52%, mean age 66.38 ± 2.85 years, and mean NIHSS 4.09 ± 0.53) under standardized conditions. EF was measured as the reactive hyperemia index (RHI), logarithm of RHI (lnRHI), and Framingham RHI (fRHI). Measurements were separated by 1.5 and 24 h to assess same-day and day-to-day reliability, respectively.ResultsFair to moderate correlations of measurements [intraclass correlation coefficient (ICC)same-day 0.29 and ICCday-to-day 0.52] were detected in healthy subjects. In stroke patients, we found moderate to substantial correlation of both same-day and day-to-day repeated measurements (ICCsame-day 0.40 and ICCday-to-day 0.62). fRHI compared with RHI and lnRHI showed best reliability.ConclusionRepeated measurements of fRHI in stroke patients show moderate reliability on same-day and substantial on day-to-day measurements. Likewise, in healthy subjects there was substantial reliability on day-to-day measurement, but only moderate on same-day measurements. In general, day-to-day correlation of repeated EF measurements was far better than that of same-day measurements, which ranged from poor to moderate depending on the specific outcome measure of EF. A possible carryover effect should be considered if same-day repeated testing of drug effects is applied in future studies
Incorporation of excluded volume correlations into Poisson-Boltzmann theory
We investigate the effect of excluded volume interactions on the electrolyte
distribution around a charged macroion. First, we introduce a criterion for
determining when hard-core effects should be taken into account beyond standard
mean field Poisson-Boltzmann (PB) theory. Next, we demonstrate that several
commonly proposed local density functional approaches for excluded volume
interactions cannot be used for this purpose. Instead, we employ a non-local
excess free energy by using a simple constant weight approach. We compare the
ion distribution and osmotic pressure predicted by this theory with Monte Carlo
simulations. They agree very well for weakly developed correlations and give
the correct layering effect for stronger ones. In all investigated cases our
simple weighted density theory yields more realistic results than the standard
PB approach, whereas all local density theories do not improve on the PB
density profiles but on the contrary, deviate even more from the simulation
results.Comment: 23 pages, 7 figures, 1 tabl
Environmental Radioactivity in the North Atlantic Region. The Faroe Islands and Greenland included. 1985
Environmental radioactivity in the North Atlantic Region. The Faroe Islands and Greenland included. 1984
Natural iron enrichment around the Antarctic Peninsula in the Southern Ocean
As part of the US-AMLR program in January-February of 2006, 99 stations in
the South Shetland Islands-Antarctic Peninsula region were sampled to
understand the variability in hydrographic and biological properties related
to the abundance and distribution of krill in this area. Concentrations of
dissolved iron (DFe) and total acid-leachable iron (TaLFe) were measured in
the upper 150 m at 16 of these stations (both coastal and pelagic waters) to
better resolve the factors limiting primary production in this area and in
downstream waters of the Scotia Sea. The concentrations of DFe and TaLFe in
the upper mixed layer (UML) were relatively high in Weddell Sea Shelf Waters
(~0.6 nM and 15 nM, respectively) and low in Drake Passage waters
(~0.2 nM and 0.9 nM, respectively). In the Bransfield
Strait, representing a mixture of waters from the Weddell Sea and the
Antarctic Circumpolar Current (ACC), concentrations of DFe were ~0.4 nM
and of TaLFe ~1.7 nM. The highest concentrations of DFe and TaLFe
in the UML were found at shallow coastal stations close to Livingston Island
(~1.6 nM and 100 nM, respectively). The ratio of TaLFe:DFe varied
with the distance to land: ~45 at the shallow coastal stations, ~15
in the high-salinity waters of Bransfield Strait, and ~4 in ACC
waters. Concentrations of DFe increased slightly with depth in the water
column, while that of TaLFe did not show any consistent trend with depth.
Our Fe data are discussed in regard to the hydrography and water circulation
patterns in the study area, and with the hypothesis that the relatively high
rates of primary production in the central regions of the Scotia Sea are
partially sustained by natural iron enrichment resulting
from a northeasterly flow of iron-rich coastal waters originating in
the South Shetland Islands-Antarctic Peninsula region
Environmental radioactivity in the North Atlantic Region. The Faroe Islands and Greenland included. 1983
Network governance in Russia: an analytical framework
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.This article questions the widely held notions of Russian exceptionalism as regards its state–society relations, arguing that the conceptual tools used to study governance in other regions and contexts are applicable in Russia, opening the potential for fruitful comparisons and dialogue. Our analytical framework for studying Russian governance emphasises the concept of networking. We posit that even in contemporary hybrid authoritarian regimes the state is dependent on interactive governance arrangements involving civil society actors. The article applies the analytical framework to an initial synthesis of findings from studies of Russian governance, reported elsewhere in the symposium
H-1-MRS Measured Ectopic Fat in Liver and Muscle in Danish Lean and Obese Children and Adolescents
This cross sectional study aims to investigate the associations between ectopic lipid accumulation in liver and skeletal muscle and biochemical measures, estimates of insulin resistance, anthropometry, and blood pressure in lean and overweight/obese children.Fasting plasma glucose, serum lipids, serum insulin, and expressions of insulin resistance, anthropometry, blood pressure, and magnetic resonance spectroscopy of liver and muscle fat were obtained in 327 Danish children and adolescents aged 8-18 years.In 287 overweight/obese children, the prevalences of hepatic and muscular steatosis were 31% and 68%, respectively, whereas the prevalences in 40 lean children were 3% and 10%, respectively. A multiple regression analysis adjusted for age, sex, body mass index z-score (BMI SDS), and pubertal development showed that the OR of exhibiting dyslipidemia was 4.2 (95%CI: [1.8; 10.2], p = 0.0009) when hepatic steatosis was present. Comparing the simultaneous presence of hepatic and muscular steatosis with no presence of steatosis, the OR of exhibiting dyslipidemia was 5.8 (95%CI: [2.0; 18.6], p = 0.002). No significant associations between muscle fat and dyslipidemia, impaired fasting glucose, or blood pressure were observed. Liver and muscle fat, adjusted for age, sex, BMI SDS, and pubertal development, associated to BMI SDS and glycosylated hemoglobin, while only liver fat associated to visceral and subcutaneous adipose tissue and intramyocellular lipid associated inversely to high density lipoprotein cholesterol.Hepatic steatosis is associated with dyslipidemia and liver and muscle fat depositions are linked to obesity-related metabolic dysfunctions, especially glycosylated hemoglobin, in children and adolescents, which suggest an increased cardiovascular disease risk
Magnetic ground state and magnon-phonon interaction in multiferroic h-YMnO
Inelastic neutron scattering has been used to study the magneto-elastic
excitations in the multiferroic manganite hexagonal YMnO. An avoided
crossing is found between magnon and phonon modes close to the Brillouin zone
boundary in the -plane. Neutron polarization analysis reveals that this
mode has mixed magnon-phonon character. An external magnetic field along the
-axis is observed to cause a linear field-induced splitting of one of the
spin wave branches. A theoretical description is performed, using a Heisenberg
model of localized spins, acoustic phonon modes and a magneto-elastic coupling
via the single-ion magnetostriction. The model quantitatively reproduces the
dispersion and intensities of all modes in the full Brillouin zone, describes
the observed magnon-phonon hybridized modes, and quantifies the magneto-elastic
coupling. The combined information, including the field-induced magnon
splitting, allows us to exclude several of the earlier proposed models and
point to the correct magnetic ground state symmetry, and provides an effective
dynamic model relevant for the multiferroic hexagonal manganites.Comment: 12 pages, 10 figure
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