Search results for " Gradient"

Analisi dei pattern di distribuzione di Posidonia oceanica lungo gradienti batimetrici

2011

Influence diagnostics for generalized linear mixed models: a gradient-like statistic

2013

In the literature, many influence measures proposed for Generalized Linear Mixed Models (GLMMs) require the information matrix that can be difficult to calculate. In the present paper, a known influence measure is approximated to get a simpler form, for which the information matrix is no more necessary. The proposed measure is showed to have a form similar to the gradient statistic, recently introduced. Good performances have been obtained through simulation studies.

Modified apparatus for voltage gradient gel electrophoresis.

1999

We built a modified version of voltage gradient gel electrophoresis system to correct distortions in nucleic acids electrophoretic migration patterns occurring at the edges of the gel when the original voltage gradient apparatus is used. The new device allows correct fractionation of nucleic acids also when electrophoresis is performed at high voltages.

Orthogonal electrophoretic fractionation of DNA in agarose gels.

2008

We developed an electrophoretic procedure, using Voltage Gradient Gel Electrophoresis (VGGE), which allows to obtain both an improvement of the resolution power of the system in orthogonal fractionation of DNA and, mainly, an about fourfold enhancement of hybridization signals in Southern blotting applications.

Enhanced hybridization labeling signals in Southern blotted DNAs fractionated with voltage gradient gel electrophoresis.

1998

An enhancement of hybridization labeling signals is demonstrated in Southern blotted DNAs, fractionated by voltage gradient gel electrophoresis. This enhancement is due to a reduced thickness of each single nucleic acid band in the gel as a consequence of the gradient effect, corresponding to an increased concentration of DNA per unit area.

A rapid and simple method for the preparation of yeast mitochondrial DNA

1990

Bounded solutions to the 1-Laplacian equation with a critical gradient term

2012

The genetics of human migration: Tracing migrations through the genome

2015

Various academic disciplines shed light on human migrations, helping us to reconstruct the past. Studying the genetic diversity of human populations today reveals past demographic and migratory events that have left an imprint on our genome. Armed with knowledge of migrations in prehistoric times, we can test hypotheses put forward in other scientific disciplines. Similarly, the distribution of genetic diversity in the future will largely depend on today’s extensive human migrations, facilitated by technological advances.

Downy-oak woods of Italy: phytogeographical remarks on a controversial taxonomic and ecologic issue

2014

The importance of downy oak as an integral component of the "submediterranean" woods has been underscored by many studies. Nevertheless, terms like "submediterranean" and "downy oak" are some of the most poorly understood concepts in European phytogeographic and taxonomic research. Downy oak is well known to be a problematic taxon. The name "Quercus pubescens" (= Q. humilis) combines populations characterized by increasing phenotypic and genomic polymorphisms along north-south gradients, which is explained as the result of a "founder effect" produced by a relatively fast post-glacial re-colonization of the northern areas through rare long-distance dispersal events. On the other hand, polymo…

Assessment of the Geochemical Potential in a Complex Tectonic Environment of South-East Sicily: New Insights From Hydrochemical Data

2019

We analyzed a large dataset (143 water sampling sites, 22 variables) of chemical parameters in local groundwaters from the south-east sector of Sicily, namely the Hyblean plateau, in order to set an original evaluation of its geothermal potential using applied geochemistry. The area was affected by volcanism until about 1.4 Ma. Today, though no active volcanism occurs, it is site of surface gas manifestations of focused degassing to which a mantle source has been attributed. We identified and thence selected the most promising sites (water springs and wells) based both on their main geochemical characteristics and on their calculated equilibrium temperature (resulting in the range between 5…