Search results for "population diversity"
showing 7 items of 7 documents
Multilocus sequence typing analysis of Italian Xanthomonas campestris pv. campestris strains suggests the evolution of local endemic populations of t…
2019
Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot in Brassicaceae. It is widespread in Italy and severe outbreaks occur under conditions that favour disease development. In this study a multilocus sequence typing approach (MLST) based on the partial sequence of seven loci was applied to a selection of strains representative of the main areas of cultivation and hosts. The aim was to investigate whether the long tradition of brassica crops in Italy has influenced the evolution of different Xcc populations. All loci were polymorphic; 14 allelic profiles were identified of which 13 were unique to Italian strains. Based on the seven loci, the most common genotype withi…
Ancient and recent admixture layers in Sicily and Southern Italy trace multiple migration routes along the Mediterranean
2017
The Mediterranean shores stretching between Sicily, Southern Italy and the Southern Balkans witnessed a long series of migration processes and cultural exchanges. Accordingly, present-day population diversity is composed by multiple genetic layers, which make the deciphering of different ancestral and historical contributes particularly challenging. We address this issue by genotyping 511 samples from 23 populations of Sicily, Southern Italy, Greece and Albania with the Illumina GenoChip Array, also including new samples from Albanian-and Greek-speaking ethno-linguistic minorities of Southern Italy. Our results reveal a shared Mediterranean genetic continuity, extending from Sicily to Cypru…
The impact of virus population diversity on the dynamics of cytomegalovirus DNAemia in allogeneic stem cell transplant recipients
2017
Mixed cytomegalovirus (CMV) infections are associated with delayed viral clearance in solid organ transplant recipients. We investigated whether this could be extrapolated to allogeneic stem cell transplant (allo-SCT) recipients. A total of 48 plasma specimens, obtained during 29 episodes of active CMV infection in 25 non-consecutive allo-SCT patients, were analysed. Baseline blood specimens, drawn shortly prior to the inception of pre-emptive antiviral therapy (pre-treatment specimen; n=29), as well as follow-up samples obtained either after the initiation of antiviral therapy (post-treatment specimen; n=15) or during recurrent episodes (n=4) were analysed. Plasma CMV DNA loads were quanti…
An Analysis of the Influence of Noneffective Instructions in Linear Genetic Programming
2020
Abstract Linear Genetic Programming (LGP) represents programs as sequences of instructions and has a Directed Acyclic Graph (DAG) dataflow. The results of instructions are stored in registers that can be used as arguments by other instructions. Instructions that are disconnected from the main part of the program are called noneffective instructions, or structural introns. They also appear in other DAG-based GP approaches like Cartesian Genetic Programming (CGP). This article studies four hypotheses on the role of structural introns: noneffective instructions (1) serve as evolutionary memory, where evolved information is stored and later used in search, (2) preserve population diversity, (3)…
Lack of Population Diversity in Commonly Used Human Embryonic Stem-Cell Lines
2009
To the Editor: Human embryonic stem-cell research may lead to new methods of drug discovery, insights into mechanisms of disease, and eventually, cellular therapies. The potential benefit to patient populations may depend partially on the diversity of the stem-cell lines that are available for research and clinical use. However, investigators have been unable to target their research to diverse subgroups of existing lines or to ensure the inclusion of lines from the human populations most relevant to their diseases of interest, because almost no information has been available on the human population origin of existing stem-cell lines. Therefore, with the . . .
Variability of Christmas rose (Helleborus niger L.) populations and its potential use in genetic breeding
2005
International audience; The Christmas rose (Helleborus niger L.) is widely distributed in Southern and Central Europe, and Slovenia is probably one of the centers of its diversity. The investigation was aimed at evaluating phenotypic diversity among selected wild populations in Slovenia and neighboring Croatia. Some of the analyzed traits expressed relatively very high variation (e.g., number of leaves per plant, number of inflorescences per plant). The variation ranges of some of the analyzed traits were found to be wider than those mentioned in the literature. Statistical analysis indicated that variability was more expressed within than between populations. In terms of present market req…