Search results for "Synchronism"

The Spatial Dimension in Population Fluctuations

1997

Theoretical research into the dynamics of coupled populations has suggested a rich ensemble of spatial structures that are created and maintained either by external disturbances or self-reinforcing interactions among the populations. Long-term data of the Canadian lynx from eight Canadian provinces display large-scale spatial synchrony in population fluctuations. The synchronous dynamics are not time-invariant, however, as pairs of populations that are initially in step may drift out of phase and back into phase. These observations are in agreement with predictions of a spatially-linked population model and support contemporary population ecology theory.

A rapid spectrofluorimetric method for the determination of the degree of synchronism inSaccharomyces cerevisiae

1985

A fluorescence technique that allows direct measurement of DNA and synchrony levels inSaccharomyces cerevisiae cell cultures is reported. The spectrofluorimetric estimation of DNA with 4,6-diamidino-2-phenylindole (AT-dye) does not require prior extraction, is highly stable, and requires small quantities of cells.

La battaglia di Himera nelle Storie di Erodoto e il sincronismo con Salamina

2022

The very short report of the battle of Himera given by Herodotus’ Histories seems to have the primary aim of supporting a widespread tradition among the inhabitants of Sicily (still circulating at the time when the historian lived) about the true reason preventing Gelon from siding with the Hellenic League against Persians: he was impelled to engage in the battle of Himera, which took place the very same day as the sea battle of Salamis. No celebratory intent emerges from the account of Gelon’s and Theron’s victory over the Carthaginians, since Herodotus wants to report all the versions known to him about the explanations given to Gelon’s refusal to join the Hellenic League; there is no roo…

First-degree atrioventricular block and pseudopacemaker syndrome

2013

Quantitative study of cardiac wall motion from cine-MRI using frequency-based optical flow methods

2010

The aim of this thesis is to study parietal desynchronisation of the left ventricle from conventional cine-MRI. The first part of our work consisted in the quantification of the left ventricle wall motion of the heart directly from conventional retrospective SSFP type cine-MRI sequences used in the study of cardiac function. The developed methods for measuring displacements within the images are frequency-based optical flow methods. These techniques seem to be particularly adapted to MRI specificities. We have demonstrated their robustness in the event of Rician noise and pixel intensity variations as a function of time. These variations are often associated with the through-plane motion of…