Search results for " Populations"
showing 10 items of 173 documents
Il disegno campionario e il piano di rilevazione nell’indagine sui turisti incoming in partenza dalla Sicilia e dalla Sardegna: il campionamento spaz…
2011
This paper aims to describe the sample design and the survey plan used in the survey on incoming tourism in Sicily and Sardinia. The specific goals of the survey are related: a) to the measurement and the analysis of un-observed tourism; b) to the evaluation of tourist mobility within the two Islands; c) to the analysis of some key-factors related to the holyday experience of tourists. It is well known that regional tourists are very difficult-to-reach populations and the problems in sampling human mobile populations derive from the absence of a list of units component units (frame). Despite these issues are well-known in literature under the broader categories of hard to reach, or hidden, …
Host–virus evolutionary dynamics with specialist and generalist infection strategies: Bifurcations, bistability, and chaos
2019
In this work, we have investigated the evolutionary dynamics of a generalist pathogen, e.g., a virus population, that evolves toward specialization in an environment with multiple host types. We have particularly explored under which conditions generalist viral strains may rise in frequency and coexist with specialist strains or even dominate the population. By means of a nonlinear mathematical model and bifurcation analysis, we have determined the theoretical conditions for stability of nine identified equilibria and provided biological interpretation in terms of the infection rates for the viral specialist and generalist strains. By means of a stability diagram, we identified stable fixed…
Genome-Wide Analyses Identifies Known and New Markers Responsible of Chicken Plumage Color
2020
Simple Summary In order to assess sources of variation related to Polverara breed plumage color (black vs. white), we carried out genome-wide analyses to identify the genomic regions involved in this trait. The present work has revealed new candidate genes involved in the phenotypic variability in local chicken populations. These results also contribute insights into the genetic basis for plumage color in poultry, and confirm the great complexity of the mechanisms that control this trait. Abstract Through the development of the high-throughput genotyping arrays, molecular markers and genes related to phenotypic traits have been identified in livestock species. In poultry, plumage color is a…
Importance sampling for Lambda-coalescents in the infinitely many sites model
2011
We present and discuss new importance sampling schemes for the approximate computation of the sample probability of observed genetic types in the infinitely many sites model from population genetics. More specifically, we extend the 'classical framework', where genealogies are assumed to be governed by Kingman's coalescent, to the more general class of Lambda-coalescents and develop further Hobolth et. al.'s (2008) idea of deriving importance sampling schemes based on 'compressed genetrees'. The resulting schemes extend earlier work by Griffiths and Tavar\'e (1994), Stephens and Donnelly (2000), Birkner and Blath (2008) and Hobolth et. al. (2008). We conclude with a performance comparison o…
The protection of the person in medical research in the Spanish law.
2002
AbstractNo Abstract
Genome-wide detection of signatures of selection in three Valdostana cattle populations
2020
International audience; The Valdostana is a local dual purpose cattle breed developed in Italy. Three populations are recognized within this breed, based on coat colour, production level, morphology and temperament: Valdostana Red Pied (VPR), Valdostana Black Pied (VPN) and Valdostana Chestnut (VCA). Here, we investigated putative genomic regions under selection among these three populations using the Bovine 50K SNP array by combining three different statistical methods based either on allele frequencies (F-ST) or extended haplotype homozygosity (iHS and Rsb). In total, 8, 5 and 8 chromosomes harbouring 13, 13 and 16 genomic regions potentially under selection were identified by at least tw…
An Interaction Path of Mothers’ and Preschoolers’ Food-and Physical Activity-Related Aspects in Disadvantaged Sicilian Urban Areas
2021
Background: The relationship between mothers and their children’s lifestyle is still unclear, especially in disadvantaged areas. Consequently, the study aims to identify a path explaining the extent to which maternal eating habits and physical activity (PA) level predict food-related aspects, PA practice and Quotient of Gross Motor Development (QGMD) in preschoolers from disadvantaged urban areas. Methods: In this cross-sectional study, a total of 79 dyads of mothers and children were recruited from kindergartens. Information related to family socio-demographic aspects, mothers’ and children’s dietary intake frequencies and PA/sedentariness, mothers’ weight and height, mothers’ perception o…
Sensory & consumer studies with special populations: children and elderly
2015
revue créée en 2015; The need to adapt the usual sensory methods to face the particularities of children and elderly has been emphasized since many years. A diversity of methods that could be used with children according to their developmental stage, and to a lesser extent with elderly depending on their cognitive status, have been described. This review aims at underlining limits but also possibilities for measuring, in children and elderly, sensory reactions, food acceptance and also for exploring cognitive aspects of food perception. The main points to conduct successfully sensory and consumer studies with these populations are highlighted.
Ecological Complex Systems
2008
Main aim of this topical issue is to report recent advances in noisy nonequilibrium processes useful to describe the dynamics of ecological systems and to address the mechanisms of spatio-temporal pattern formation in ecology both from the experimental and theoretical points of view. This is in order to understand the dynamical behaviour of ecological complex systems through the interplay between nonlinearity, noise, random and periodic environmental interactions. Discovering the microscopic rules and the local interactions which lead to the emergence of specific global patterns or global dynamical behaviour and the noises role in the nonlinear dynamics is an important, key aspect to unders…
The Social Nature of Chronic Noncommunicable Diseases and How to Tackle Them Through Communication Technology, Training, and Outreach
2011
As world leaders prepare for the United Nations High Level Meeting on Noncommunicable Diseases, to take place in September 2011, international organizations, nongovernmental organizations, and economic and business fora have created new alliances and initiatives to accelerate research, advocacy, and political commitment. This article argues that the time is propitious to reflect on the social nature of the most common behavioral noncommunicable disease determinants, including tobacco and alcohol use, physical inactivity, and unhealthy diet. Evidence is presented related to the fact that these diseases are profoundly rooted in social and community ties and points to the need for a modern com…