996 resultados para Polymorphism for ancestry-admixture mapping


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Defining digital humanities might be an endless debate if we stick to the discussion about the boundaries of this concept as an academic "discipline". In an attempt to concretely identify this field and its actors, this paper shows that it is possible to analyse them through Twitter, a social media widely used by this "community of practice". Based on a network analysis of 2,500 users identified as members of this movement, the visualisation of the "who's following who?" graph allows us to highlight the structure of the network's relationships, and identify users whose position is particular. Specifically, we show that linguistic groups are key factors to explain clustering within a network whose characteristics look similar to a small world.

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Clines in chromosomal inversion polymorphisms-presumably driven by climatic gradients-are common but there is surprisingly little evidence for selection acting on them. Here we address this long-standing issue in Drosophila melanogaster by using diagnostic single nucleotide polymorphism (SNP) markers to estimate inversion frequencies from 28 whole-genome Pool-seq samples collected from 10 populations along the North American east coast. Inversions In(3L)P, In(3R)Mo, and In(3R)Payne showed clear latitudinal clines, and for In(2L)t, In(2R)NS, and In(3R)Payne the steepness of the clinal slopes changed between summer and fall. Consistent with an effect of seasonality on inversion frequencies, we detected small but stable seasonal fluctuations of In(2R)NS and In(3R)Payne in a temperate Pennsylvanian population over 4 years. In support of spatially varying selection, we observed that the cline in In(3R)Payne has remained stable for >40 years and that the frequencies of In(2L)t and In(3R)Payne are strongly correlated with climatic factors that vary latitudinally, independent of population structure. To test whether these patterns are adaptive, we compared the amount of genetic differentiation of inversions versus neutral SNPs and found that the clines in In(2L)t and In(3R)Payne are maintained nonneutrally and independent of admixture. We also identified numerous clinal inversion-associated SNPs, many of which exhibit parallel differentiation along the Australian cline and reside in genes known to affect fitness-related traits. Together, our results provide strong evidence that inversion clines are maintained by spatially-and perhaps also temporally-varying selection. We interpret our data in light of current hypotheses about how inversions are established and maintained.

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Peer-reviewed

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When analyzing the chromosomal polymorphism of D. subobscura natural populations it is assumed that the information provided by wild males and sons of wild females is equivalent. Thus, using both in the analysis it is possible to increase the sample size. However, it is important to verify whether there are significant differences between both groups or not. The aim of this research has been to statistically compare the results of chromosomal polymorphism of both groups. We have used data from Avala Mountain (Serbia) where D. subobscura flies were collected from the 30th May to the 5th June 2011. Avala is located 18 km south of Belgrade and the trapping place is a forest with polydominant communities of Fagetum submontanum Table 1. Number and percentage of adult flies collected in Font Groga (Barcelona, Spain) on 9th October 2013. Males and sons of wild females were crossed with virgin females of the Küsnacht strain. Third instar larvae from F1 were dissected to obtain the salivary glands and the polytene chromosomes were stained and squashed in aceto-orcein solution. No significant differences were observed for any chromosome of the karyotype: A (p-value = 0.485), J (p-value = 0.230), U (p-value =0.572), E (p-value = 0.536), and O (p-value = 0.338). Thus, it seems that the two groups can be grouped together to obtain the chromosomal polymorphism of the population.

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Simultaneous localization and mapping(SLAM) is a very important problem in mobile robotics. Many solutions have been proposed by different scientists during the last two decades, nevertheless few studies have considered the use of multiple sensors simultane¬ously. The solution is on combining several data sources with the aid of an Extended Kalman Filter (EKF). Two approaches are proposed. The first one is to use the ordinary EKF SLAM algorithm for each data source separately in parallel and then at the end of each step, fuse the results into one solution. Another proposed approach is the use of multiple data sources simultaneously in a single filter. The comparison of the computational com¬plexity of the two methods is also presented. The first method is almost four times faster than the second one.

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Neuropeptide Y (NPY) is a widely expressed neurotransmitter in the central and peripheral nervous systems. Thymidine 1128 to cytocine substitution in the signal sequence of the preproNPY results in a single amino acid change where leucine is changed to proline. This L7P change leads to a conformational change of the signal sequence which can have an effect on the intracellular processing of NPY. The L7P polymorphism was originally associated with higher total and LDL cholesterol levels in obese subjects. It has also been associated with several other physiological and pathophysiological responses such as atherosclerosis and T2 diabetes. However, the changes on the cellular level due to the preproNPY signal sequence L7P polymorphism were not known. The aims of the current thesis were to study the effects of the [p.L7]+[p.L7] and the [p.L7]+[p.P7] genotypes in primary cultured and genotyped human umbilical vein endothelial cells (HUVEC), in neuroblastoma (SK-N-BE(2)) cells and in fibroblast (CHO-K1) cells. Also, the putative effects of the L7P polymorphism on proliferation, apoptosis and LDL and nitric oxide metabolism were investigated. In the course of the studies a fragment of NPY targeted to mitochondria was found. With the putative mitochondrial NPY fragment the aim was to study the translational preferences and the mobility of the protein. The intracellular distribution of NPY between the [p.L7]+[p.L7] and the [p.L7]+[p.P7] genotypes was found to be different. NPY immunoreactivity was prominent in the [p.L7]+[p.P7] cells while the proNPY immunoreactivity was prominent in the [p.L7]+[p.L7] genotype cells. In the proliferation experiments there was a difference in the [p.L7]+[p.L7] genotype cells between early and late passage (aged) cells; the proliferation was raised in the aged cells. NPY increased the growth of the cells with the [p.L7]+[p.P7] genotype. Apoptosis did not seem to differ between the genotypes, but in the aged cells with the [p.L7]+[p.L7] genotype, LDL uptake was found to be elevated. Furthermore, the genotype seemed to have a strong effect on the nitric oxide metabolism. The results indicated that the mobility of NPY protein inside the cells was increased within the P7 containing constructs. The existence of the mitochondria targeted NPY fragment was verified, and translational preferences were proved to be due to the origin of the cells. Cell of neuronal origin preferred the translation of mature NPY (NPY1-36) when compared to the non neuronal cells that translated both, NPY and the mitochondrial fragment of NPY. The mobility of the mitochondrial fragment was found to be minimal. The functionality of the mitochondrial NPY fragment remains to be investigated. L7P polymorphism in the preproNPY causes a series of intracellular changes. These changes may contribute to the state of cellular senescence, vascular tone and lead to endothelial dysfunction and even to increased susceptibility to diseases, like atherosclerosis and T2 diabetes.

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Since 1978, the unity of Geodynamics of the University of Girona has been publishing a series of detailed geological and geomorphological maps of different municipal terms of the Province of Girona, mainly on the scale of 1:10.000, situated for the major part in the Littoral and Prelittoral mountain ranges of the Cadena Costera Catalana. These mountain ranges are constituted of materials belonging to the palaeozoic era, basically metamorphous and igneous rocks (plutomc and hypoabyssal rocks)

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Robotic platforms have advanced greatly in terms of their remote sensing capabilities, including obtaining optical information using cameras. Alongside these advances, visual mapping has become a very active research area, which facilitates the mapping of areas inaccessible to humans. This requires the efficient processing of data to increase the final mosaic quality and computational efficiency. In this paper, we propose an efficient image mosaicing algorithm for large area visual mapping in underwater environments using multiple underwater robots. Our method identifies overlapping image pairs in the trajectories carried out by the different robots during the topology estimation process, being this a cornerstone for efficiently mapping large areas of the seafloor. We present comparative results based on challenging real underwater datasets, which simulated multi-robot mapping

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Rob Kitchin, geógrafo muy activo y prolífico, mantiene una intensa actividad editorial, puesto que dirige colecciones de temas geográficos y forma parte de los comités asesores de varias revistas internacionales de primera línea, entre ellas, Social and Cultural Geography, que se publica bimensualmente desde el año 2000 y de la que es director. Precisamente, en esta revista dedicada a temas relacionados con la geografía cultural y social se halla el origen de este libro, uno de cuyos propósitos iniciales fue desafiar la hegemonía anglosajona que domina el panorama geográfico internacional.

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Webben är en enorm källa för information. Innehållet på webbsidorna är en synlig typ av information, men webben innehåller även information av en annan typ, en mera gömd typ i form av sambanden och nätverken som hyperlänkarna skapar mellan webbsajterna och –sidorna som de kopplar ihop. Forskningsområdet webometri ämnar, bland annat, att skapa ny kunskap ur denna gömda information som finns inbyggt i hyperlänkarna samt att skapa förståelse för hurudana fenomen och förhållanden utanför webben kan finnas representerade i hyperlänkarna. Målet med denna forskning var att öka förståelse för användningen av hyperlänkar på webben och speciellt kommunernas användning av hyperlänkar. Denna forskning undersökte hur kommunerna i Egentliga Finland skapade och mottog hyperlänkar samt hurudana nätverk formades av dessa hyperlänkar. Forskningen kartlade nätverk av direkta länkar mellan kommunerna och av samlänkar till och från kommunerna och undersökte ifall dessa nätverk kunde användas för att undersöka geopolitiska förhållanden och samarbete mellan kommunerna i Egentliga Finland. De övergripande forskningsfrågorna som har besvarats i denna forskning är: 1) Från ett webometriskt perspektiv, hur använder kommunerna i Egentliga Finland webben? 2) Kan hyperlänkar (direkta länkar och samlänkar) användas för att kartlägga geopolitiska förhållanden och samarbete mellan kommuner? 3) Vilka är de viktigaste motiveringarna för att skapa länkar mellan, till och från kommunernas webbsajter? Denna forskning kom till ovanligt tydliga resultat för en webometrisk forskning, både när det gäller upptäckta geografiska faktorer som påverkar hyperlänkningarna och de klassificerade motivationerna för att skapa länkarna. Resultaten visade att de direkta hyperlänkarna mellan kommunerna kan användas för att kartlägga geopolitiska förhållanden och samarbete mellan kommunerna för att de direkta länkarna var motiverade av officiella orsaker och de var klart påverkade av distansen mellan kommunerna och av de ekonomiska regionerna. Samlänkningarna in till kommunerna visade sig fungera som ett mått för geografisk likhet mellan kommunerna, medan samlänkningarna ut från kommunerna visade potential för att kunna användas till för att kartlägga kommunernas gemensamma intressen. Forskningen kontribuerade även till utvecklandet av forskningsområdet webometri. En del av de viktigaste kontributionerna av denna forskning var utvecklandet av nya metoder för webometrisk forskning samt att öka kunskap om hur existerande metoder från nätverksanalys kan användas effektivt för webometrisk forskning. Resultaten från denna forskning och de utvecklade metoderna kan användas för snabba kartläggningar av diverse förhållanden mellan olika organisationer och företag genom att använda information gratis tillgängligt på webben.

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The population genetic structure of the endangered tree species Aspidosperma polyneuron Mull.Arg. (Apocynaceae) was reported based on analysis of esterase polymorphism in two remanant populations. Allelic variation was detected at three isoesterase loci (Est-3, Est-9, and Est-10). The proportion of polymorphic loci for both populations was 30% and deviation from Hardy-Weinberg equilibrium was observed for the Est-3 locus observed in the northern population. Segregation distortion and the lower level of observed and expected heterozygosity in this population were attributed to founder genotype. The high genetic identity values for northern and northwestern populations are in accordance with the low levels of interpopulation genetic divergence demonstrated by the F(ST) (0.03) value. The F(IS) value (0.23) indicated moderate levels of inbreeding. A. polyneuron can be indicated as an example of endangered species suggesting high genetic variation in contrast to the low genetic variation reported for endangered species. The esterase isozymes may be a good genetic marker for studies of natural A. polyneuron populations.

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The present work aimed to characterize and identify QTLs for wood quality and growth traits in E. grandis x E. urophylla hybrids. For this purpose a RAPD linkage map was developed for the hybrids (LOD=3 and r=0.40) containing 52 markers and 12 linkage groups. Traits related to wood quality and growth were evaluated in the QTL analyses. QTL analyses were performed using chi-square tests, single-marker, interval mapping and composite interval mapping analyses. All approaches led to the identification of similar QTLs associated with wood density, cellulose pulp yield and percentage of extractives, which were detected and confirmed by both the interval mapping and composite interval mapping methodologies. Some QTLs regions were confirmed only by the composite interval mapping methodology: percentage of soluble lignin, percentage of insoluble lignin, CBH and total height. Overlapping QTLs regions were detected, and these, can be the result of major genes involved in the regulation and control of the growth traits by epistatic interactions. In order to evaluate the effect of early selection using RAPD molecular data, molecular markers adjacent to QTLs were used genotype selection. The analysis of selection differential values suggests that for all the traits the phenotypic selection at seven years should generate larger genetic gains than early selection assisted by molecular markers and the combination of the strategies should elevate the selection efficiency.

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This paper aims to assess the effectiveness of ASTER imagery to support the mapping of Pittosporum undulatum, an invasive woody species, in Pico da Vara Natural Reserve (S. Miguel Island, Archipelago of the Azores, Portugal). This assessment was done by applying K-Nearest Neighbor (KNN), Support Vector Machine (SVM) and Maximum Likelihood (MLC) pixel-based supervised classifications to 4 different geographic and remote sensing datasets constituted by the Visible, Near-Infrared (VNIR) and Short Wave Infrared (SWIR) of the ASTER sensor and by digital cartography associated to orography (altitude and "distance to water streams") of which the spatial distribution of Pittosporum undulatum directly depends. Overall, most performed classifications showed a strong agreement and high accuracy. At targeted species level, the two higher classification accuracies were obtained when applying MLC and KNN to the VNIR bands coupled with auxiliary geographic information use. Results improved significantly by including ecology and occurrence information of species (altitude and distance to water streams) in the classification scheme. These results show that the use of ASTER sensor VNIR spectral bands, when coupled to relevant ancillary GIS data, can constitute an effective and low cost approach for the evaluation and continuous assessment of Pittosporum undulatum woodland propagation and distribution within Protected Areas of the Azores Islands.