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S Bottani

Publications and source records attributed to S Bottani.

5 recordsLinked to original sources

Unexpected coherence and conservation.

The effects of migration in a network of patch populations, or metapopulation, are extremely important for predicting the possibility of extinctions both at a local and a global scale. Migration between patches synchronizes local populations and bestows upon them identical dynamics (coherent or synchronous oscillations), a feature that is understood to enhance the risk of global extinctions. This is one of the central theoretical arguments in the literature associated with conservation ecology. Here, rather than restricting ourselves to the study of coherent oscillations, we examine other types of synchronization phenomena that we consider to be equally important. Intermittent and out-of-phase synchronization are but two examples that force us to reinterpret some classical results of the metapopulation theory. In addition, we discuss how asynchronous processes (for example, random timing of dispersal) can paradoxically generate metapopulation synchronization, another non-intuitive result that cannot easily be explained by the standard theory.

Animal Migration↗

Dynamics of single-stranded DNA migration in denaturing polyacrylamide slab-gel electrophoresis.

We describe an original apparatus for the study of the dynamics of single stranded DNA migration. Four detectors based on laser-induced fluorescence (LIF) are equidistantly placed on one migration lane, allowing repeated measurements of the same DNA band at different positions along migration. This article presents the characteristics and performances of this system and focuses on the data analysis, showing how the multiple detection scheme enables the study of band broadening and band resolution during a migration run. Our results suggest the existence of anomalous (nonthermal) diffusion of DNA molecules during the electrophoretic process.

Bacteriophage M13↗

Mobility and activation energy of single-stranded DNA in denaturing cross-linked polyacrylamide slab gels.

An original apparatus based on laser-induced fluorescence detection is presented. One lane migration combined to four equidistant detection points allows the study of the dynamics of DNA bands during electrophoresis. We focus this article on the study of the mobility of DNA sequencing fragments as a function of temperature; mobility is determined in 4% T, 5% C and 4.3% T, 5% C cross-linked polyacrylamide gels at an electric field of 45 V/cm [T=(g acrylamide+g N,N'-methylenebisacrylamide)/100 ml solution; C=g N,N'-methylenebisacrylamide/% T]. Activation energy has been investigated under these experimental conditions with a temperature varying from 25 to 50 degrees C. The activation energy for migration through the cross-linked polyacrylamide gel decreases with fragment length under our experimental conditions and it varies along the migration.

DNA, Single-Stranded↗