548 research outputs found
Screening Instrument for Dysphagia in People with an Intellectual Disability (SD-ID):Quick and Reliable Screening by Caregivers
Background and Aim: Timely diagnosis of dysphagia is important for people with an intellectual disability. Periodic screening of each individual by speech-language therapists is barely feasible with respect to limited resources. Therefore, preselection of individuals with an increased dysphagia risk through screening by caregivers is crucial.Objective: This study aimed to develop the novel Screening instrument for Dysphagia for people with an Intellectual Disability (SD-ID).Methods: The SD-ID was developed, validated and optimised in two rounds. Version 3, consisting of nine risk factors and 20 items concerning eating/drinking behaviour, was thoroughly studied for feasibility, concurrent validity and reliability, and then optimised.Outcomes and Results: The SD-ID (version 3) was filled out in an average of four minutes (feasibility). A strong positive association was found between scores on SD-ID and Dysphagia Disorder Survey (concurrent validity). Test-retest and interrater reliability were very good. Two additional risk factors were added and two items removed to yield the final version 4. The most optimal cut-off score appeared to be either 4 or 5.Conclusions and Implications: The SD-ID is a reliable instrument to screen for an increased risk of dysphagia in people with an intellectual disability. Ideally it is part of a cyclic work process: Screening with SD-ID (step 1), diagnostic work-up if necessary (step 2), recommendations (step 3), and evaluation (step 4).</p
Quasiparticle RPA with finite rank approximation for Skyrme interactions
A finite rank separable approximation for the particle-hole RPA calculations
with Skyrme interactions is extended to take into account the pairing. As an
illustration of the method energies and transition probabilities for the
quadrupole and octupole excitations in some O, Ar, Sn and Pb isotopes are
calculated. The values obtained within our approach are very close to those
that were calculated within QRPA with the full Skyrme interaction. They are in
reasonable agreement with experimental data.Comment: 20 pages, 1 figure, submitted to Phys.Rev.
Separabelized Skyrme Interactions and Quasiparticle RPA
A finite rank separable approximation for the quasiparticle RPA with Skyrme
interactions is applied to study the low lying quadrupole and octupole states
in some S isotopes and giant resonances in some spherical nuclei. It is shown
that characteristics calculated within the suggested approach are in a good
agreement with available experimental data.Comment: 12 pages, 2 figures, proceedings of the Seventh School-Seminar on
Heavy Ion Physics, Dubna, Russia, May 27-June 1, 2002; to appear in Physics
of Atomic Nucle
Review article: defining remission in ulcerative colitis
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87130/1/j.1365-2036.2011.04701.x.pd
Chaos Driven Decay of Nuclear Giant Resonances: Route to Quantum Self-Organization
The influence of background states with increasing level of complexity on the
strength distribution of the isoscalar and isovector giant quadrupole resonance
in Ca is studied. It is found that the background characteristics,
typical for chaotic systems, strongly affects the fluctuation properties of the
strength distribution. In particular, the small components of the wave function
obey a scaling law analogous to self-organized systems at the critical state.
This appears to be consistent with the Porter-Thomas distribution of the
transition strength.Comment: 14 pages, 4 Figures, Illinois preprint P-93-12-106, Figures available
from the author
High-energy scissors mode
All the orbital M1 excitations, at both low and high energies, obtained from
a rotationally invariant QRPA, represent the fragmented scissors mode. The
high-energy M1 strength is almost purely orbital and resides in the region of
the isovector giant quadrupole resonance. In heavy deformed nuclei the
high-energy scissors mode is strongly fragmented between 17 and 25 MeV (with
uncertainties arising from the poor knowledge of the isovector potential). The
coherent scissors motion is hindered by the fragmentation and for single transitions in this region. The cross
sections for excitations above 17 MeV are one order of magnitude larger for E2
than for M1 excitations even at backward angles.Comment: 20 pages in RevTEX, 5 figures (uuencoded,put with 'figures') accepted
for publication in Phys.Rev.
Comment on "Compression Modulus of Nuclear Matter and Charge-Distribution Differences"
Regulatory control and the costs and benefits of biochemical noise
Experiments in recent years have vividly demonstrated that gene expression
can be highly stochastic. How protein concentration fluctuations affect the
growth rate of a population of cells, is, however, a wide open question. We
present a mathematical model that makes it possible to quantify the effect of
protein concentration fluctuations on the growth rate of a population of
genetically identical cells. The model predicts that the population's growth
rate depends on how the growth rate of a single cell varies with protein
concentration, the variance of the protein concentration fluctuations, and the
correlation time of these fluctuations. The model also predicts that when the
average concentration of a protein is close to the value that maximizes the
growth rate, fluctuations in its concentration always reduce the growth rate.
However, when the average protein concentration deviates sufficiently from the
optimal level, fluctuations can enhance the growth rate of the population, even
when the growth rate of a cell depends linearly on the protein concentration.
The model also shows that the ensemble or population average of a quantity,
such as the average protein expression level or its variance, is in general not
equal to its time average as obtained from tracing a single cell and its
descendants. We apply our model to perform a cost-benefit analysis of gene
regulatory control. Our analysis predicts that the optimal expression level of
a gene regulatory protein is determined by the trade-off between the cost of
synthesizing the regulatory protein and the benefit of minimizing the
fluctuations in the expression of its target gene. We discuss possible
experiments that could test our predictions.Comment: Revised manuscript;35 pages, 4 figures, REVTeX4; to appear in PLoS
Computational Biolog
Tolerance to bronchodilation during treatment with long-acting beta-agonists, a randomised controlled trial
BACKGROUND: Regular use of beta-agonists leads to tolerance to their bronchodilator effects. This can be demonstrated by measuring the response to beta-agonist following bronchoconstriction using methacholine. However most studies have demonstrated tolerance after a period of beta-agonist withdrawal, which is not typical of their use in clinical practice. This study assessed tolerance to the bronchodilator action of salbutamol during ongoing treatment with long-acting beta-agonist. METHODS: Random-order, double-blind, placebo-controlled, crossover trial. After 1 week without beta-agonists, 13 asthmatic subjects inhaled formoterol 12 μg twice daily or matching placebo for 1 week. Eight hours after the first and last doses subjects inhaled methacholine to produce a 20% fall in FEV(1). Salbutamol 100, 200 and 400 μg (cumulative dose) was then given at 5-minute intervals and FEV(1 )was measured 5 minutes after each dose. After a 1 week washout subjects crossed over to the other treatment. Unscheduled use of beta-agonists was not allowed during the study. The main outcome variable was the area under the salbutamol response curve. RESULTS: The analysis showed a significant time by treatment interaction indicating that the response to salbutamol fell during formoterol therapy compared to placebo. After 1 week of formoterol the area under the salbutamol response curve was 48% (95% confidence interval 28 to 68%) lower than placebo. This reduction in response remained significant when the analyses were adjusted for changes in the pre-challenge FEV(1 )and dose of methacholine given (p = 0.001). CONCLUSION: The bronchodilator response to salbutamol is significantly reduced in patients taking formoterol. Clinically relevant tolerance to rescue beta-agonist treatment is likely to occur in patients treated with long-acting beta-agonists
An Epigenetic Switch Involving Overlapping Fur and DNA Methylation Optimizes Expression of a Type VI Secretion Gene Cluster
Type VI secretion systems (T6SS) are macromolecular machines of the cell envelope of Gram-negative bacteria responsible for bacterial killing and/or virulence towards different host cells. Here, we characterized the regulatory mechanism underlying expression of the enteroagregative Escherichia coli sci1 T6SS gene cluster. We identified Fur as the main regulator of the sci1 cluster. A detailed analysis of the promoter region showed the presence of three GATC motifs, which are target of the DNA adenine methylase Dam. Using a combination of reporter fusion, gel shift, and in vivo and in vitro Dam methylation assays, we dissected the regulatory role of Fur and Dam-dependent methylation. We showed that the sci1 gene cluster expression is under the control of an epigenetic switch depending on methylation: fur binding prevents methylation of a GATC motif, whereas methylation at this specific site decreases the affinity of Fur for its binding box. A model is proposed in which the sci1 promoter is regulated by iron availability, adenine methylation, and DNA replication
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