Search results for "Volume effect"
showing 3 items of 3 documents
Knots in finite memory walks
2016
We investigate the occurrence and size of knots in a continuum polymer model with finite memory via Monte Carlo simulations. Excluded volume interactions are local and extend only to a fixed number of successive beads along the chain, ensuring that at short length scales the excluded volume effect dominates, while at longer length scales the polymer behaves like a random walk. As such, this model may be useful for understanding the behavior of polymers in a melt or semi-dilute solution, where exactly the same crossover is believed to occur. In particular, finite memory walks allow us to investigate the role of local interactions in the transition from highly knotted ideal polymers to almost…
Association between Cognitive Performance and Cortical Glucose Metabolism in Patients with Mild Alzheimer’s Disease
2004
<i>Background:</i> Neuronal and synaptic function in Alzheimer’s disease (AD) is measured in vivo by glucose metabolism using positron emission tomography (PET). <i>Objective:</i> We hypothesized that neuronal activation as measured by PET is a more sensitive index of neuronal dysfunction than activity during rest. We investigated if the correlations between dementia severity as measured with the Mini Mental State Examination (MMSE) and glucose metabolism are an artifact of brain atrophy. <i>Method:</i> Glucose metabolism was measured using [<sup>18</sup>F]fluorodeoxyglucose PET during rest and activation due to audiovisual stimulation in 13 m…
Blood Volume Substitutes in Emergency Care
1985
Volume substitutes for restoring circulating blood volume are eminently important for emergency care. In addition to side effects, the intravascular volume effect immediately after infusion and the duration of this volume effect are determining factors for the selection of volume replacement solutions available on the market today. Therefore, we controlled the intravascular volume effect of 16 test solutions, immediately as well as 90 and 240 min after the end of infusion.