Search results for "iho"
showing 10 items of 2277 documents
Clonal Interference and the Evolution of RNA Viruses
1999
In asexual populations, beneficial mutations that occur in different lineages compete with one another. This phenomenon, known as clonal interference, ensures that those beneficial mutations that do achieve fixation are of large effect. Clonal interference also increases the time between fixations, thereby slowing the adaptation of asexual populations. The effects of clonal interference were measured in the asexual RNA virus vesicular stomatitis virus; rates and average effects of beneficial mutations were quantified.
Molecular basis of adaptive convergence in experimental populations of RNA viruses
2002
Abstract Characterizing the molecular basis of adaptation is one of the most important goals in modern evolutionary genetics. Here, we report a full-genome sequence analysis of 21 independent populations of vesicular stomatitis ribovirus evolved on the same cell type but under different demographic regimes. Each demographic regime differed in the effective viral population size. Evolutionary convergences are widespread both at synonymous and nonsynonymous replacements as well as in an intergenic region. We also found evidence for epistasis among sites of the same and different loci. We explain convergences as the consequence of four factors: (1) environmental homogeneity that supposes an id…
Recombination drives genome evolution in outbreak-related Legionella pneumophila isolates.
2014
Legionella pneumophila is a strictly environmental pathogen and the etiological agent of legionellosis. It is known that non-vertical processes have a major role in the short-term evolution of pathogens, but little is known about the relevance of these and other processes in environmental bacteria. We report the whole-genome sequencing of 69 L. pneumophila strains linked to recurrent outbreaks in a single location (Alcoy, Spain) over 11 years. We found some examples where the genome sequences of isolates of the same sequence type and outbreak did not cluster together and were more closely related to sequences from different outbreaks. Our analyses identify 16 recombination events responsibl…
Deep metazoan phylogeny: When different genes tell different stories
2013
11 páginas, 4 figuras, 1 tabla.
Evidence of Recombination in Intrapatient Populations of Hepatitis C Virus.
2008
Hepatitis C virus (HCV) is a major cause of liver disease worldwide and a potential cause of substantial morbidity and mortality in the future. HCV is characterized by a high level of genetic heterogeneity. Although homologous recombination has been demonstrated in many members of the family Flaviviridae, to which HCV belongs, there are only a few studies reporting recombination on natural populations of HCV, suggesting that these events are rare in vivo. Furthermore, these few studies have focused on recombination between different HCV genotypes/subtypes but there are no reports on the extent of intra-genotype or intra-subtype recombination between viral strains infecting the same patient.…
Population genetic analysis of bi-allelic structural variants from low-coverage sequence data with an expectation-maximization algorithm
2014
Background Population genetics and association studies usually rely on a set of known variable sites that are then genotyped in subsequent samples, because it is easier to genotype than to discover the variation. This is also true for structural variation detected from sequence data. However, the genotypes at known variable sites can only be inferred with uncertainty from low coverage data. Thus, statistical approaches that infer genotype likelihoods, test hypotheses, and estimate population parameters without requiring accurate genotypes are becoming popular. Unfortunately, the current implementations of these methods are intended to analyse only single nucleotide and short indel variation…
Ecosocial Innovations and Their Capacity to Integrate Ecological, Economic and Social Sustainability Transition
2019
The article contributes to sustainability transition research by indicating the significance of transformative grassroots innovations in the context of social work research. We introduce the integrative concept of ecosocial innovation in order to demonstrate how grassroots innovations can successfully combine social, ecological and economic aspects of a sustainability transition. By ecosocial innovations, we refer to social innovations with a strong ecological orientation (e.g., recycling workshops, urban gardening, participatory unemployment projects and new local economies). The data consists of 50 examples of ecosocial innovations in Finland, Italy, Germany, Belgium and the UK. We invest…
Dimensions underlying frailty indicators in the Kihon Checklist.
2019
Aim Frailty has become a current topic of debate in recent years among researchers as a key concept of clinical care in old age. One of the scales developed for its measurement is the Kihon Checklist (KCL). However, the dimensionality of the KCL has not been tested yet, and therefore the aim of the present study was to validate its dimensional structure. Methods This was a cross-sectional study carried out between March and September 2018 in Valencia province (Spain). Participation in the study was voluntary. A total of 251 participants were sampled. They answered sociodemographic and medical indicators, as well as five frailty scales, including the KCL. Results Five confirmatory models wit…
Dental services utilization between 1977 and 1995 by Finnish adolescents of different socioeconomic levels.
1998
Equal distribution of health care services has long been a major goal of health policy in the Nordic countries. According to these guidelines, every child is expected to have an examination and treatment at least every second year. The aim of this study was to analyze the trends and, in particular, the socioeconomic differences in dental visits between 1977 and 1995. The data were collected as part of a nationwide research program, the Adolescent Health and Lifestyle Survey, which began in 1977. Every second year a self-administered questionnaire was mailed to a representative sample of 14-, 16- and 18-year-old Finns. The sample sizes in the surveys varied from 2422 to 9556, making a total …
Influence of immigration and other factors on caries in 12- and 15-yr-old children.
2007
In recent years the Valencia region has undergone mass immigration, mainly of people from eastern Europe, North Africa, and Latin America. The objective of this study was to assess the effect of immigration on caries prevalence and experience in 12- and 15-yr-old children in the Valencia region, and to relate this to other socio-economic and oral hygiene-related variables. The data were obtained from the epidemiological study of oral health carried out in the Valencia Region in 2004. The study group comprised 478, 12-yr-old children and 401, 15-yr-old children. Immigration status, age, toothbrushing frequency, and intake of cariogenic foods between meals showed significant association in a …