895 resultados para discriminant analysis and cluster analysis


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Tietokonejärjestelmän osien ja ohjelmistojen suorituskykymittauksista saadaan tietoa,jota voidaan käyttää suorituskyvyn parantamiseen ja laitteistohankintojen päätöksen tukena. Tässä työssä tutustutaan suorituskyvyn mittaamiseen ja mittausohjelmiin eli ns. benchmark-ohjelmistoihin. Työssä etsittiin ja arvioitiin eri tyyppisiä vapaasti saatavilla olevia benchmark-ohjelmia, jotka soveltuvat Linux-laskentaklusterin suorituskyvynanalysointiin. Benchmarkit ryhmiteltiin ja arvioitiin testaamalla niiden ominaisuuksia Linux-klusterissa. Työssä käsitellään myös mittausten tekemisen ja rinnakkaislaskennan haasteita. Benchmarkkeja löytyi moneen tarkoitukseen ja ne osoittautuivat laadultaan ja laajuudeltaan vaihteleviksi. Niitä on myös koottu ohjelmistopaketeiksi, jotta laitteiston suorituskyvystä saisi laajemman kuvan kuin mitä yhdellä ohjelmalla on mahdollista saada. Olennaista on ymmärtää nopeus, jolla dataa saadaan siirretyä prosessorille keskusmuistista, levyjärjestelmistä ja toisista laskentasolmuista. Tyypillinen benchmark-ohjelma sisältää paljon laskentaa tarvitsevan matemaattisen algoritmin, jota käytetään tieteellisissä ohjelmistoissa. Benchmarkista riippuen tulosten ymmärtäminen ja hyödyntäminen voi olla haasteellista.

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Pseudomonas fluorescens CHA0 and the related strain Pf-5 are well-characterized representatives of rhizosphere bacteria that have the capacity to protect crop plants from fungal root diseases, mainly by releasing a variety of exoproducts that are toxic to plant pathogenic fungi. Here, we report that the two plant-beneficial pseudomonads also exhibit potent insecticidal activity. Anti-insect activity is linked to a novel genomic locus encoding a large protein toxin termed Fit (for P. fluorescensinsecticidal toxin) that is related to the insect toxin Mcf (Makes caterpillars floppy) of the entomopathogen Photorhabdus luminescens, a mutualist of insect-invading nematodes. When injected into the haemocoel, even low doses of P. fluorescens CHA0 or Pf-5 killed larvae of the tobacco hornworm Manduca sexta and the greater wax moth Galleria mellonella. In contrast, mutants of CHA0 or Pf-5 with deletions in the Fit toxin gene were significantly less virulent to the larvae. When expressed from an inducible promoter in a non-toxic Escherichia coli host, the Fit toxin gene was sufficient to render the bacterium toxic to both insect hosts. Our findings establish the Fit gene products of P. fluorescens CHA0 and Pf-5 as potent insect toxins that define previously unappreciated anti-insect properties of these plant-colonizing bacteria

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Background: The 22q11.2 deletion syndrome is the most frequent genomic disorder with an estimated frequency of 1/4000 live births. The majority of patients (90%) have the same deletion of 3 Mb (Typically Deleted Region, TDR) that results from aberrant recombination at meiosis between region specific low-copy repeats (LCRs). Methods: As a first step towards the characterization of recombination rates and breakpoints within the 22q11.2 region we have constructed a high resolution recombination breakpoint map based on pedigree analysis and a population-based historical recombination map based on LD analysis. Results: Our pedigree map allows the location of recombination breakpoints with a high resolution (potential recombination hotspots), and this approach has led to the identification of 5 breakpoint segments of 50 kb or less (8.6 kb the smallest), that coincide with historical hotspots. It has been suggested that aberrant recombination leading to deletion (and duplication) is caused by low rates of Allelic Homologous Recombination (AHR) within the affected region. However, recombination rate estimates for 22q11.2 region show that neither average recombination rates in the 22q11.2 region or within LCR22-2 (the LCR implicated in most deletions and duplications), are significantly below chromosome 22 averages. Furthermore, LCR22-2, the repeat most frequently implicated in rearrangements, is also the LCR22 with the highest levels of AHR. In addition, we find recombination events in the 22q11.2 region to cluster within families. Within this context, the same chromosome recombines twice in one family; first by AHR and in the next generation by NAHR resulting in an individual affected with the del22q11.2 syndrome. Conclusion: We show in the context of a first high resolution pedigree map of the 22q11.2 region that NAHR within LCR22 leading to duplications and deletions cannot be explained exclusively under a hypothesis of low AHR rates. In addition, we find that AHR recombination events cluster within families. If normal and aberrant recombination are mechanistically related, the fact that LCR22s undergo frequent AHR and that we find familial differences in recombination rates within the 22q11.2 region would have obvious health-related implications.

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The objective of research was to analyse the potential of Normalized Difference Vegetation Index (NDVI) maps from satellite images, yield maps and grapevine fertility and load variables to delineate zones with different wine grape properties for selective harvesting. Two vineyard blocks located in NE Spain (Cabernet Sauvignon and Syrah) were analysed. The NDVI was computed from a Quickbird-2 multi-spectral image at veraison (July 2005). Yield data was acquired by means of a yield monitor during September 2005. Other variables, such as the number of buds, number of shoots, number of wine grape clusters and weight of 100 berries were sampled in a 10 rows × 5 vines pattern and used as input variables, in combination with the NDVI, to define the clusters as alternative to yield maps. Two days prior to the harvesting, grape samples were taken. The analysed variables were probable alcoholic degree, pH of the juice, total acidity, total phenolics, colour, anthocyanins and tannins. The input variables, alone or in combination, were clustered (2 and 3 Clusters) by using the ISODATA algorithm, and an analysis of variance and a multiple rang test were performed. The results show that the zones derived from the NDVI maps are more effective to differentiate grape maturity and quality variables than the zones derived from the yield maps. The inclusion of other grapevine fertility and load variables did not improve the results.

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Tutkimus tarkastelee Luoteis-Venäjän liikennelogistiikkaklusteria. Tarkoitus on selvittää klusterin nykyinen rakenne ja kilpailukyky sekä klusterin tarjoamat liiketoimintamahdollisuudet suomalaisille logistiikkayrityksille. Työssä käsitellään neljää perusliikennemuotoa: rautatie-, maantie-, meri- ja sisävesi-, sekä ilmaliikennettä. Tutkimuksen aineisto on kerätty tutkimusta varten laadituista kyselyistä, haastatteluista sekä aiemmin julkaistusta materiaalista. Venäjä on suunnitellut kehittävänsä voimakkaasti liikenneinfrastruktuuria, mm. julkaisemalla protektionistisen liikennestrategiasuunnitelman. Ongelmana ovat olleet toteutukset, jotka ovat jääneet yleensä puutteellisiksi. Tällä hetkellä todellista kilpailukykyä löytyy ainoastaan rautatieliikenteestä, muut kolme liikennemuotoa omaavat potentiaalisen kilpailukyvyn. Venäjällä on mahdollisuus hyötyä laajasta pinta-alastaan Aasian ja Euroopan liikenteen yhdistäjänä. Yksi konkreettisimmista esimerkeistä on Trans Siperian rautatie, joka kaipaisi vielä lisäkehitystä. Suomi on toiminut Venäjän liikenteessä arvotavaran kauttakulkumaana, vuonna 2003 noin 30–40 % Venäjän tuonnin arvosta kulki Suomen kautta. Venäjälle tullaan tuomaan arvotavaraa vielä useita vuosia, mutta reittien osalta kilpailu on tiukentunut. Suomalaisten yritysten liiketoimintamahdollisuuksiin esitetään kaksi mallia: kauttakulkuliikenteen lisäarvologistiset (VAL) operaatiot Suomessa tai etabloituminen Venäjän logistisiin ketjuihin. Suomalaisten olisi syytä parantaa yhteistyötään yritysten ja yliopistojen ym. koulutuslaitosten välillä. Myös yhteistyökumppaneiden hakeminen esimerkiksi Ruotsista voisi tuoda merkittäviä etuja. Suomalaista osaamista voitaisiin hyödyntää parhaiten etabloitumalla Venäjän markkinoille, esimerkiksi keskittymällä Venäjän logististen ketjujen johtamiseen. Myös VAL palveluiden johtamiseen Venäjällä olisi erittäin hyvä tilaisuus, koska Venäjän oma tietotaito logistiikassa ei ole vielä kehittynyt kansainväliselle tasolle, mutta kustannustaso on alhaisempi kuin Suomessa.

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BACKGROUND AND OBJECTIVE: Gastroschisis is a congenital anomaly with increasing incidence, easy prenatal diagnosis and extremely variable postnatal outcomes. Our objective was to systematically review the evidence regarding the association between prenatal ultrasound signs (intraabdominal bowel dilatation [IABD], extraabdominal bowel dilatation, gastric dilatation [GD], bowel wall thickness, polyhydramnios, and small for gestational age) and perinatal outcomes in gastroschisis (bowel atresia, intra uterine death, neonatal death, time to full enteral feeding, length of total parenteral nutrition and length of in hospital stay). METHODS: Medline, Embase, and Cochrane databases were searched electronically. Studies exploring the association between antenatal ultrasound signs and outcomes in gastroschisis were considered suitable for inclusion. Two reviewers independently extracted relevant data regarding study characteristics and pregnancy outcome. All meta-analyses were computed using individual data random-effect logistic regression, with single study as the cluster unit. RESULTS: Twenty-six studies, including 2023 fetuses, were included. We found significant positive associations between IABD and bowel atresia (odds ratio [OR]: 5.48, 95% confidence interval [CI] 3.1-9.8), polyhydramnios and bowel atresia (OR: 3.76, 95% CI 1.7-8.3), and GD and neonatal death (OR: 5.58, 95% CI 1.3-24.1). No other ultrasound sign was significantly related to any other outcome. CONCLUSIONS: IABD, polyhydramnios, and GD can be used to an extent to identify a subgroup of neonates with a prenatal diagnosis of gastroschisis at higher risk to develop postnatal complications. Data are still inconclusive on the predictive ability of several signs combined, and large prospective studies are needed to improve the quality of prenatal counseling and the neonatal care for this condition.

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Background: We use an approach based on Factor Analysis to analyze datasets generated for transcriptional profiling. The method groups samples into biologically relevant categories, and enables the identification of genes and pathways most significantly associated to each phenotypic group, while allowing for the participation of a given gene in more than one cluster. Genes assigned to each cluster are used for the detection of pathways predominantly activated in that cluster by finding statistically significant associated GO terms. We tested the approach with a published dataset of microarray experiments in yeast. Upon validation with the yeast dataset, we applied the technique to a prostate cancer dataset. Results: Two major pathways are shown to be activated in organ-confined, non-metastatic prostate cancer: those regulated by the androgen receptor and by receptor tyrosine kinases. A number of gene markers (HER3, IQGAP2 and POR1) highlighted by the software and related to the later pathway have been validated experimentally a posteriori on independent samples. Conclusion: Using a new microarray analysis tool followed by a posteriori experimental validation of the results, we have confirmed several putative markers of malignancy associated with peptide growth factor signalling in prostate cancer and revealed others, most notably ERRB3 (HER3). Our study suggest that, in primary prostate cancer, HER3, together or not with HER4, rather than in receptor complexes involving HER2, could play an important role in the biology of these tumors. These results provide new evidence for the role of receptor tyrosine kinases in the establishment and progression of prostate cancer.

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The main goal of the InterAmbAr reseach project is to analyze the relationships between landscape systems and human land-use strategies on mountains and littoral plains from a long-term perspective. The study adopts a high resolution analysis of small-scale study areas located in the Mediterranean region of north-eastern Catalonia. The study areas are distributed along an altitudinal transect from the high mountain (above 2000m a.s.l.) to the littoral plain of Empordà (Fig. 1). High resolution interdisciplinary research has been carried out from 2010, based on the integration of palaeoenvironmental and archaeological data. The micro-scale approach is used to understand human-environmental relationships. It allows better understanding of the local-regional nature of environmental changes and the synergies between catchment-based systems, hydro-sedimentary regimes, human mobility, land-uses, human environments, demography, etc.

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Mechanisms underlying speciation in plants include detrimental (incompatible) genetic interactions between parental alleles that incur a fitness cost in hybrids. We reported on recessive hybrid incompatibility between an Arabidopsis thaliana strain from Poland, Landsberg erecta (Ler), and many Central Asian A. thaliana strains. The incompatible interaction is determined by a polymorphic cluster of Toll/interleukin-1 receptor-nucleotide binding-leucine rich repeat (TNL) RPP1 (Recognition of Peronospora parasitica1)-like genes in Ler and alleles of the receptor-like kinase Strubbelig Receptor Family 3 (SRF3) in Central Asian strains Kas-2 or Kond, causing temperature-dependent autoimmunity and loss of growth and reproductive fitness. Here, we genetically dissected the RPP1-like Ler locus to determine contributions of individual RPP1-like Ler (R1R8) genes to the incompatibility. In a neutral background, expression of most RPP1-like Ler genes, except R3, has no effect on growth or pathogen resistance. Incompatibility involves increased R3 expression and engineered R3 overexpression in a neutral background induces dwarfism and sterility. However, no individual RPP1-like Ler gene is sufficient for incompatibility between Ler and Kas-2 or Kond, suggesting that co-action of at least two RPP1-like members underlies this epistatic interaction. We find that the RPP1-like Ler haplotype is frequent and occurs with other Ler RPP1-like alleles in a local population in Gorzów Wielkopolski (Poland). Only Gorzów individuals carrying the RPP1-like Ler haplotype are incompatible with Kas-2 and Kond, whereas other RPP1-like alleles in the population are compatible. Therefore, the RPP1-like Ler haplotype has been maintained in genetically different individuals at a single site, allowing exploration of forces shaping the evolution of RPP1-like genes at local and regional population scales.

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The phenotypic and genetic diversity of 77 isolates of Pyricularia grisea collected from two upland rice cultivars, Maravilha and Primavera, was studied. Isolates exhibiting compatible reaction to cv.Primavera were incompatible to cv.Maravilha and vice versa, with the exception of six isolates that were compatible to both cultivars. The virulence of isolates from cv. Maravilha on 32 test genotypes of rice was significantly higher (t = 9.09, p < 0.0001) than the isolates from cv.Primavera. A phenogram constructed from virulence data showed two main groups, one constituted mainly of isolates from cv.Primavera (97.6%) and the other of isolates from cv.Maravilha (91.17%). Rep-PCR analysis of isolates using two primers designed from sequences of Pot2 showed that isolates could be clustered broadly into two groups. The average similarity within a cluster of isolates from cv.Primavera was significantly greater than the average similarity among the isolates of cv.Maravilha (t = 5.37, p < 0.0001). There was close correspondence between clusters based on PCR and virulence data (r = 0.48, p < 0.011). The results showed that isolates of P. grisea were cultivar specific and had low phenotypic and genetic diversity.

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The penetration resistance (PR) is a soil attribute that allows identifies areas with restrictions due to compaction, which results in mechanical impedance for root growth and reduced crop yield. The aim of this study was to characterize the PR of an agricultural soil by geostatistical and multivariate analysis. Sampling was done randomly in 90 points up to 0.60 m depth. It was determined spatial distribution models of PR, and defined areas with mechanical impedance for roots growth. The PR showed a random distribution to 0.55 and 0.60 m depth. PR in other depths analyzed showed spatial dependence, with adjustments to exponential and spherical models. The cluster analysis that considered sampling points allowed establishing areas with compaction problem identified in the maps by kriging interpolation. The analysis with main components identified three soil layers, where the middle layer showed the highest values of PR.

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A 40-kb DNA region containing the major cluster of nif genes has been isolated from the Azospirillum brasilense Sp7 genome. In this region three nif operons have been identified: nifHDKorf1Y, nifENXorf3orf5fdxAnifQ and orf2nifUSVorf4. The operons containing nifENX and nifUSV genes are separated from the structural nifHDKorf1Y operon by about 5 kb and 10 kb, respectively. The present study shows the sequence analysis of the 6045-bp DNA region containing the nifENX genes. The deduced amino acid sequences from the open reading frames were compared to the nif gene products of other diazotrophic bacteria and indicate the presence of seven ORFs, all reading in the same direction as that of the nifHDKorf1Y operon. Consensus sigma54 and NifA-binding sites are present only in the promoter region upstream of the nifE gene. This promoter is activated by NifA protein and is approximately two-times less active than the nifH promoter, as indicated by the ß-galactosidase assays. This result suggests the differential expression of the nif genes and their respective products in Azospirillum.

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The contents of total phenolic compounds (TPC), total flavonoids (TF), and ascorbic acid (AA) of 18 frozen fruit pulps and their scavenging capacities against peroxyl radical (ROO•), hydrogen peroxide (H2O2), and hydroxyl radical (•OH) were determined. Principal Component Analysis (PCA) showed that TPC (total phenolic compounds) and AA (ascorbic acid) presented positive correlation with the scavenging capacity against ROO•, and TF (total flavonoids) showed positive correlation with the scavenging capacity against •OH and ROO• However, the scavenging capacity against H2O2 presented low correlation with TF (total flavonoids), TPC (total phenolic compounds), and AA (ascorbic acid). The Hierarchical Cluster Analysis (HCA) allowed the classification of the fruit pulps into three groups: one group was formed by the açai pulp with high TF, total flavonoids, content (134.02 mg CE/100 g pulp) and the highest scavenging capacity against ROO•, •OH and H2O2; the second group was formed by the acerola pulp with high TPC, total phenolic compounds, (658.40 mg GAE/100 g pulp) and AA , ascorbic acid, (506.27 mg/100 g pulp) contents; and the third group was formed by pineapple, cacao, caja, cashew-apple, coconut, cupuaçu, guava, orange, lemon, mango, passion fruit, watermelon, pitanga, tamarind, tangerine, and umbu pulps, which could not be separated considering only the contents of bioactive compounds and the scavenging properties.

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Genome sequence varies in numerous ways among individuals although the gross architecture is fixed for all humans. Retrotransposons create one of the most abundant structural variants in the human genome and are divided in many families, with certain members in some families, e.g., L1, Alu, SVA, and HERV-K, remaining active for transposition. Along with other types of genomic variants, retrotransponson-derived variants contribute to the whole spectrum of genome variants in humans. With the advancement of sequencing techniques, many human genomes are being sequenced at the individual level, fueling the comparative research on these variants among individuals. In this thesis, the evolution and functional impact of structural variations is examined primarily focusing on retrotransposons in the context of human evolution. The thesis comprises of three different studies on the topics that are presented in three data chapters. First, the recent evolution of all human specific AluYb members, representing the second most active subfamily of Alus, was tracked to identify their source/master copy using a novel approach. All human-specific AluYb elements from the reference genome were extracted, aligned with one another to construct clusters of similar copies and each cluster was analyzed to generate the evolutionary relationship between the members of the cluster. The approach resulted in identification of one major driver copy of all human specific Yb8 and the source copy of the Yb9 lineage. Three new subfamilies within the AluYb family – Yb8a1, Yb10 and Yb11 were also identified, with Yb11 being the youngest and most polymorphic. Second, an attempt to construct a relation between transposable elements (TEs) and tandem repeats (TRs) was made at a genome-wide scale for the first time. Upon sequence comparison, positional cross-checking and other relevant analyses, it was observed that over 20% of all TRs are derived from TEs. This result established the first connection between these two types of repetitive elements, and extends our appreciation for the impact of TEs on genomes. Furthermore, only 6% of these TE-derived TRs follow the already postulated initiation and expansion mechanisms, suggesting that the others are likely to follow a yet-unidentified mechanism. Third, by taking a combination of multiple computational approaches involving all types of genetic variations published so far including transposable elements, the first whole genome sequence of the most recent common ancestor of all modern human populations that diverged into different populations around 125,000-100,000 years ago was constructed. The study shows that the current reference genome sequence is 8.89 million base pairs larger than our common ancestor’s genome, contributed by a whole spectrum of genetic mechanisms. The use of this ancestral reference genome to facilitate the analysis of personal genomes was demonstrated using an example genome and more insightful recent evolutionary analyses involving the Neanderthal genome. The three data chapters presented in this thesis conclude that the tandem repeats and transposable elements are not two entirely distinctly isolated elements as over 20% TRs are actually derived from TEs. Certain subfamilies of TEs themselves are still evolving with the generation of newer subfamilies. The evolutionary analyses of all TEs along with other genomic variants helped to construct the genome sequence of the most recent common ancestor to all modern human populations which provides a better alternative to human reference genome and can be a useful resource for the study of personal genomics, population genetics, human and primate evolution.

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The distribution and activity of communities of sulfate-reducing bacteria (SRB) and methanogenic archaea in two contrasting Antarctic sediments were investigated. Methanogenesis dominated in freshwater Lake Heywood, while sulfate reduction dominated in marine Shallow Bay. Slurry experiments indicated that 90% of the methanogenesis in Lake Heywood was acetoclastic. This finding was supported by the limited diversity of clones detected in a Lake Heywood archaeal clone library, in which most clones were closely related to the obligate acetate-utilizing Methanosaeta concilii. The Shallow Bay archaeal clone library contained clones related to the C-1-utilizing Methanolobus and Methanococcoides and the H-2-utilizing Methanogenium. Oligonucleotide probing of RNA extracted directly from sediment indicated that archaea represented 34% of the total prokaryotic signal in Lake Heywood and that Methanosaeta was a major component (13.2%) of this signal. Archaea represented only 0.2% of the total prokaryotic signal in RNA extracted from Shallow Bay sediments. In the Shallow Bay bacterial clone library, 10.3% of the clones were SRB-like, related to Desulfotalea/Desulforhopalus, Desulfofaba, Desulfosarcina, and Desulfobacter as well as to the sulfur and metal oxidizers comprising the Desulfuromonas cluster. Oligonucleotide probes for specific SRB clusters indicated that SRB represented 14.7% of the total prokaryotic signal, with Desulfotalea/Desulforhopalus being the dominant SRB group (10.7% of the total prokaryotic signal) in the Shallow Bay sediments; these results support previous results obtained for Arctic sediments. Methanosaeta and Desulfotalea/Desulforhopalus appear to be important in Lake Heywood and Shallow Bay, respectively, and may be globally important in permanently low-temperature sediments.