Browsing by Subject "Cluster Analysis"

Now showing 1 - 6 of 6
  • No Thumbnail Available
    Item
    Cystic echinococcosis in Turkey: Genetic variability and first record of the pig strain (G7) in the country
    (2009) Šnábel V.; Altintas N.; D'Amelio S.; Nakao M.; Romig T.; Yolasigmaz A.; Gunes K.; Turk M.; Busi M.; Hüttner M.; Ševcová D.; Ito A.; Dubinský P.
    A sample of 22 Echinococcus granulosus isolates collected from 12 sheep and ten humans from a focus of cystic echinococcosis in western Turkey was examined by DNA sequencing of four mitochondrial genes (cox1, atp6, nad1, rrnS). Results demonstrated the presence of two species of E. granulosus complex, E. granulosus sensu stricto and E. canadensis. Of E. granulosus sensu stricto, the G1 genotype (including three microvariants) was found in 17 isolates from humans and sheep, the G3 genotype and an intermediate form G1/G3 in one isolate each (both from sheep). Of E. canadensis, the pig strain G7 was found in three isolates from sheep and human. This is the first report of this strain in Turkey. Its presence has implications for local control programs due to its shorter maturation rate in dogs compared with E. granulosus sensu stricto. Goat and/or wild boar are likely reservoirs for G7 in the region. We provided further data on the pattern and frequency of nucleotide substitutions within the G1/G3 cluster. Based on our results and GenBank records, G2 (Tasmanian sheep strain) is not considered as a discrete genotypic unit, as its sequences at polymorphic sites conform to microvariants of both G1 and (more often) G3. © 2009 Springer-Verlag.
  • No Thumbnail Available
    Item
    Comparison of similarity coefficients used for cluster analysis based on RAPD markers in wild olives.
    (2010) Sesli M.; Yegenoglu E.D.
    Five different similarity coefficients (Jaccard, Sorensen-Dice, simple matching, Rogers and Tanimoto, and Russel and Rao) were evaluated and 10 wild olives analyzed with RAPD markers. The influence of the similarity coefficients on wild olives clustering was investigated. Forty-five primers were used on samples from 10 wild olives (Wild 1 and 2 obtained from Mugla province; Wild 3, 4, 5, 6, 7, and 8 from Manisa province and Wild 9 and 10 from Izmir province of Turkey). The similarity matrices obtained from RAPD markers were compared by the Mantel test. Cluster analysis was made with UPGMA dendrograms, and the consensus fork indexes between all pairs of dendrograms were calculated. The Jaccard and Sorensen-Dice coefficients gave the same results, due to the fact that both exclude negative co-occurrences. The dendrograms using the simple matching and Rogers and Tanimoto coefficients were similar; Wild 4 (Akhisar, Manisa) and Wild 9 (Bornova, Izmir) olives had the closest genetic similarities. This occurred because these coefficients include negative co-occurrences. The Russel and Rao coefficients produced different results, because they include negative co-occurrences in the denominator. We concluded that the coefficients that do not include negative co-occurrences are more efficient for studies of wild olives clustering based on RAPD markers.
  • No Thumbnail Available
    Item
    Genetic relationships among and within wild and cultivated olives based on RAPDs.
    (2010) Sesli M.; Yeǧenoǧlu E.D.
    We examined genetic relationships among wild and cultivated olives, which is a very important crop in the economy of the Aegean region. We used RAPD analysis to evaluate relationships among and within 22 olive subspecies from Manisa, Mugla and Izmir provinces in Turkey. Twelve of the subspecies were wild and 10 were cultivated olives. Fifty-two primers were used (OP-Q 1-20, OP-I 1-20, OP-F 14-15-16-17, and OP-K 1-8) and 49 polymorphic bands were selected and used for analysis. The dendrogram based on unweighted pair-group cluster analysis using the Sorensen-Dice coefficient of similarity index indicated two major groups, dividing wild olives from cultivated olives. The patterns of genetic relationships among and within the different olives were analyzed by means of analysis of molecular variance. We found significant differences between wild and cultivated olives (Phi(st) = 0.1507; P < 0.001). In order to determine the genetic relationship among wild and cultivated olives, principal coordinate analysis was used to examine the variation among subspecies. The wild and cultivated olives formed two main groups, one on the right side and the other on the left side of the principal coordinates graph, respectively. This was compatible with the results we obtained from analysis of molecular variance.
  • No Thumbnail Available
    Item
    Pandoraea oxalativorans sp. nov., Pandoraea faecigallinarum sp. nov. and Pandoraea vervacti sp. nov., isolated from oxalate-enriched culture
    (2011) Sahin N.; Tani A.; Kotan R.; Sedláček I.; Kimbara K.; Tamer A.U.
    Five isolates, designated TA2, TA4, TA25 T KOx T and NS15 T were isolated in previous studies by enrichment in mineral medium with potassium oxalate as the sole carbon source and were characterized using a polyphasic approach. The isolates were Gram-reaction-negative, aerobic, non-spore-forming rods. Phylogenetic analyses based on 16S rRNA and DNA gyrase B subunit (gyrB) gene sequences confirmed that the isolates belonged to the genus Pandoraea and were most closely related to Pandoraea sputorum and Pandoraea pnomenusa (97.2-99.7% 16S rRNA gene sequence similarity). The isolates could be differentiated from their closest relatives on the basis of several phenotypic characteristics. The major cellular fatty acid profiles of the isolates comprised C 16: 0, C 18: 1 ω 7c, C17: 0 cyclo and summed feature 3 (C 16: 1ω7c and/or iso-C15: 0 2-OH). On the basis of DNA-DNA hybridization studies and phylogenetic analyses, the isolates represent three novel species within the genus Pandoraea, for which the names Pandoraea oxalativorans sp. nov. (TA25 T 5NBRC 106091 T 5CCM 7677 T 5DSM 23570 T), Pandoraea faecigallinarum sp. nov. (KOx T 5NBRC 106092 T 5CCM 2766 T 5DSM 23572 T) and Pandoraea vervacti sp. nov. (NS15 T 5NBRC 106088 T 5CCM 7667 T 5DSM 23571) are proposed. © 2011 IUMS.
  • No Thumbnail Available
    Item
    Biomedical Text Categorization Based on Ensemble Pruning and Optimized Topic Modelling
    (Hindawi Limited, 2018) Onan A.
    Text mining is an important research direction, which involves several fields, such as information retrieval, information extraction, and text categorization. In this paper, we propose an efficient multiple classifier approach to text categorization based on swarm-optimized topic modelling. The Latent Dirichlet allocation (LDA) can overcome the high dimensionality problem of vector space model, but identifying appropriate parameter values is critical to performance of LDA. Swarm-optimized approach estimates the parameters of LDA, including the number of topics and all the other parameters involved in LDA. The hybrid ensemble pruning approach based on combined diversity measures and clustering aims to obtain a multiple classifier system with high predictive performance and better diversity. In this scheme, four different diversity measures (namely, disagreement measure, Q-statistics, the correlation coefficient, and the double fault measure) among classifiers of the ensemble are combined. Based on the combined diversity matrix, a swarm intelligence based clustering algorithm is employed to partition the classifiers into a number of disjoint groups and one classifier (with the highest predictive performance) from each cluster is selected to build the final multiple classifier system. The experimental results based on five biomedical text benchmarks have been conducted. In the swarm-optimized LDA, different metaheuristic algorithms (such as genetic algorithms, particle swarm optimization, firefly algorithm, cuckoo search algorithm, and bat algorithm) are considered. In the ensemble pruning, five metaheuristic clustering algorithms are evaluated. The experimental results on biomedical text benchmarks indicate that swarm-optimized LDA yields better predictive performance compared to the conventional LDA. In addition, the proposed multiple classifier system outperforms the conventional classification algorithms, ensemble learning, and ensemble pruning methods. © 2018 Aytuǧ Onan.
  • No Thumbnail Available
    Item
    Detection of permethrin resistance and phylogenetic clustering of turkish head lice (Pediculus humanus capitis; De Geer, 1767 populations
    (Elsevier B.V., 2020) Karakuş M.; Atıcı T.; Karabela Ş.N.; Baylan O.; Limoncu M.E.; Balcıoğlu İ.C.
    Head lice infestation caused by Pediculus humanus capitis De Geer, 1767 is one of the most common public health problems. The relationship between humans and head lice dates back millions of years ago that differentiated into different phylogenetic clades. Treatment of head lice infestation usually based on insecticide-based products, which promotes the resistance in the head lice populations. In the present study, we aimed to screen the presence of permethrin resistance among collected P. h. capitis specimens in Turkey. Three mutation sites (T917I, L920F, and M815I) were screened using real-time PCR and resistance was identified by melt analysis. Of the studied specimens, resistance allele frequency (RAF) was found 0.98 for T917I, 0.99 for L920F, and 1.00 for M815I. The phylogenetic study revealed that Clade A and Clade B are present and overlap in Turkey. The present study is first to screen the resistance among Turkish head lice specimens. To not stimulate the pyrethroids resistance in head lice populations, early detection of resistance is crucial and will help the health professionals to choose suitable formula in the treatment. We suggest that the resistance status needs to be screened in randomly selected populations before any treatment application is given. © 2020 Elsevier B.V.