925 resultados para clonal integration
Resumo:
Individual fitness and the structure of marine communities are strongly affected by spatial competition. Among the most common space holders are the colonial ascidians, which have the ability to monopolize large areas of hard substrate, overgrowing most other competitors. The effects of competition on colony growth and on gonad production of the ascidian Didemnum perlucidum were studied in southeastern Brazil by experimentally removing surrounding competitors. Colonies of D, perlucidum competing for space exhibited a growth rate 9 times less than that of colonies that were competitor free. Among the colonies subject to competition, growth rates were unrelated to the percentage of colony border that was free of competitors. However, the identity of the competitor was important in the outcome of border contacts. At the beginning of the experiment, most border encounters of D. perlucidum were with solitary organisms, which in most cases were overgrown. These were progressively replaced by colonial ascidians and bryozoans, resulting mostly in stand-off interactions. Besides reducing asexual growth, spatial competition also affected female gonad production. Colonies free of competitors had a significantly higher proportion of zooids with ovaries. Thus, our findings show that spatial competition reduces both ascidian colony size and gonad production.
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Chronic exposure of pancreatic beta-cells to saturated non-esterified fatty acids can lead to inhibition of insulin secretion and apoptosis. Several previous studies have demonstrated that saturated fatty acids such as PA (palmitic acid) are detrimental to beta-cell function compared with unsaturated fatty acids. In the present study, we describe the effect of the polyunsaturated AA (arachidonic acid) on the function of the clonal pancreatic beta-cell line BRIN-BD11 and demonstrate AA-dependent attenuation of PA effects. When added to beta-cell incubations at 100 mu M, AA can stimulate cell proliferation and chronic (24 h) basal insulin secretion. Microarray analysis and/or real-time PCR indicated significant AA-dependent up-regulation of genes involved in proliferation and fatty acid metabolism [e.g. Angptl (angiopoietin-like protein 4), Ech1 (peroxisomal Delta(3.5),Delta(2.4)-dienoyl-CoA isomerase), Cox-1 (cyclo-oxygenase-1) and Cox-2, P < 0.05]. Experiments using specific COX and LOX (lipoxygenase) inhibitors demonstrated the importance of COX-1 activity for acute (20 min) stimulation of insulin secretion, suggesting that AA metabolites may be responsible for the insulinotropic effects. Moreover, concomitant incubation of AA with PA dose-dependently attenuated the detrimental effects of the saturated fatty acid, so reducing apoptosis and decreasing parameters of oxidative stress [ROS (reactive oxygen species) and NO levels] while improving the GSH/GSSG ratio. AA decreased the protein expression of iNOS (inducible NO synthase), the p65 subunit of NF-kappa B (nuclear factor kappa B) and the p47 subunit of NADPH oxidase in PA-treated cells. These findings indicate that AA has an important regulatory and protective beta-cell action, which may be beneficial to function and survival in the `lipotoxic` environment commonly associated with Type 2 diabetes mellitus.
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Background/aim: The purpose of this study was to determine the bacterial diversity in the subgingival plaque of subjects with generalized aggressive periodontitis by using culture-independent molecular methods based on 16S ribosomal DNA cloning. Methods: Samples from 10 subjects with generalized aggressive periodontitis were selected. DNA was extracted and the 16S rRNA gene was amplified with the universal primer pairs 9F and 1525R. Amplified genes were cloned, sequenced, and identified by comparison with known 16S rRNA sequences. Results: One hundred and ten species were identified from 10 subjects and 1007 clones were sequenced. Of these, 70 species were most prevalent. Fifty-seven percent of the clone (40 taxa) sequences represented phylotypes for which no cultivated isolates have been reported. Several species of Selenomonas and Streptococcus were found at high prevalence and proportion in all subjects. Overall, 50% of the clone libraries were formed by these two genera. Selenomonas sputigena, the species most commonly detected, was found in nine of 10 subjects. Other species of Selenomonas were often present at high levels, including S. noxia, Selenomonas sp. EW084, Selenomonas sp. EW076, Selenomonas FT050, Selenomonas sp. P2PA_80, and Selenomonas sp. strain GAA14. The classical putative periodontal pathogens, such as, Aggregatibacter actinomycetemcomitans, was below the limit of detection and was not detected. Conclusion: These data suggest that other species, notably species of Selenomonas, may be associated with disease in generalized aggressive periodontitis subjects.
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Background and Objective: This study evaluated the prevalence and the molecular diversity of Archaea in the subgingival biofilm samples of subjects with peri-implantitis. Material and Methods: Fifty subjects were assigned into two groups: Control (n = 25), consisting of subjects with healthy implants; and Test (n = 25), consisting of subjects with peri-implantitis sites, as well as a healthy implant. In the Test group, subgingival biofilm samples were taken from the deepest sites of the diseased implant. In both groups, subgingival biofilm was collected from one site with a healthy implant and from one site with a periodontally healthy tooth. DNA was extracted and the 16S ribosomal RNA gene was amplified with universal primer pairs for Archaea. Amplified genes were cloned and sequenced, and the phylotypes were identified by comparison with known 16S ribosomal RNA sequences. Results: In the Control group, Archaea were detected in two and three sites of the implant and the tooth, respectively. In the Test group, Archaea were detected in 12, 4 and 2 sites of diseased implants, healthy implants and teeth, respectively. Diseased implants presented a significantly higher prevalence of Archaea in comparison with healthy implants and natural teeth, irrespective of group. Over 90% of the clone libraries were formed by Methanobrevibacter oralis, which was detected in both groups. Methanobacterium congelense/curvum was detected in four subjects from the Test group and in two subjects from the Control group. Conclusion: Although M. oralis was the main species of Archaea associated with both healthy and diseased implant sites, the data indicated an increased prevalence of Archaea in peri-implantitis sites, and their role in pathogenesis should be further investigated.
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Optimized experimental conditions for extracting accurate information at subpixel length scales from analyzer-based X-ray imaging were obtained and applied to investigate bone regeneration by means of synthetic beta-TCP grafting materials in a rat calvaria model. The results showed a 30% growth in the particulate size due to bone ongrowth/ingrowth within the critical size defect over a 1-month healing period.
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This paper proposes a method to locate and track people by combining evidence from multiple cameras using the homography constraint. The proposed method use foreground pixels from simple background subtraction to compute evidence of the location of people on a reference ground plane. The algorithm computes the amount of support that basically corresponds to the ""foreground mass"" above each pixel. Therefore, pixels that correspond to ground points have more support. The support is normalized to compensate for perspective effects and accumulated on the reference plane for all camera views. The detection of people on the reference plane becomes a search for regions of local maxima in the accumulator. Many false positives are filtered by checking the visibility consistency of the detected candidates against all camera views. The remaining candidates are tracked using Kalman filters and appearance models. Experimental results using challenging data from PETS`06 show good performance of the method in the presence of severe occlusion. Ground truth data also confirms the robustness of the method. (C) 2010 Elsevier B.V. All rights reserved.
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A myriad of methods are available for virtual screening of small organic compound databases. In this study we have successfully applied a quantitative model of consensus measurements, using a combination of 3D similarity searches (ROCS and EON), Hologram Quantitative Structure Activity Relationships (HQSAR) and docking (FRED, FlexX, Glide and AutoDock Vina), to retrieve cruzain inhibitors from collected databases. All methods were assessed individually and then combined in a Ligand-Based Virtual Screening (LBVS) and Target-Based Virtual Screening (TBVS) consensus scoring, using Receiving Operating Characteristic (ROC) curves to evaluate their performance. Three consensus strategies were used: scaled-rank-by-number, rank-by-rank and rank-by-vote, with the most thriving the scaled-rank-by-number strategy, considering that the stiff ROC curve appeared to be satisfactory in every way to indicate a higher enrichment power at early retrieval of active compounds from the database. The ligand-based method provided access to a robust and predictive HQSAR model that was developed to show superior discrimination between active and inactive compounds, which was also better than ROCS and EON procedures. Overall, the integration of fast computational techniques based on ligand and target structures resulted in a more efficient retrieval of cruzain inhibitors with desired pharmacological profiles that may be useful to advance the discovery of new trypanocidal agents.
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In this report, we describe the microfabrication and integration of planar electrodes for contactless conductivity detection on polyester-toner (PT) electrophoresis microchips using toner masks. Planar electrodes were fabricated by three simple steps: (i) drawing and laser-printing the electrode geometry on polyester films, (ii) sputtering deposition onto substrates, and (iii) removal of toner layer by a lift-off process. The polyester film with anchored electrodes was integrated to PT electrophoresis microchannels by lamination at 120 degrees C in less than 1 min. The electrodes were designed in an antiparallel configuration with 750 mu m width and 750 gm gap between them. The best results were recorded with a frequency of 400 kHz and 10 V-PP using a sinusoidal wave. The analytical performance of the proposed microchip was evaluated by electrophoretic separation of potassium, sodium and lithium in 150 mu m wide x 6 mu m deep microchannels. Under an electric field of 250 V/cm the analytes were successfully separated in less than 90 s with efficiencies ranging from 7000 to 13 000 plates. The detection limits (S/N = 3) found for K+, Na+, and Li+ were 3.1, 4.3, and 7.2 mu mol/L, respectively. Besides the low-cost and instrumental simplicity, the integrated PT chip eliminates the problem of manual alignment and gluing of the electrodes, permitting more robustness and better reproducibility, therefore, more suitable for mass production of electrophoresis microchips.
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This presentation was offered as part of the CUNY Library Assessment Conference, Reinventing Libraries: Reinventing Assessment, held at the City University of New York in June 2014.
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I takt med att GIS (Grafiska InformationsSystem) blir allt vanligare och mer användarvänligt har WM-data sett att kunder skulle ha intresse i att kunna koppla information från sin verksamhet till en kartbild. Detta för att lättare kunna ta till sig informationen om hur den geografiskt finns utspridd över ett område för att t.ex. ordna effektivare tranporter. WM-data, som det här arbetet är utfört åt, avser att ta fram en prototyp som sedan kan visas upp för att påvisa för kunder och andra intressenter att detta är möjligt att genomföra genom att skapa en integration mellan redan befintliga system. I det här arbetet har prototypen tagits fram med skogsindustrin och dess lager som inriktning. Befintliga program som integrationen ska skapas mellan är båda webbaserade och körs i en webbläsare. Analysprogrammet som ska användas heter Insikt och är utvecklat av företaget Trimma, kartprogrammet heter GIMS som är WM-datas egna program. Det ska vara möjligt att i Insikt analysera data och skapa en rapport. Den ska sedan skickas till GIMS där informationen skrivs ut på kartan på den plats som respektive information hör till. Det ska även gå att välja ut ett eller flera områden i kartan och skicka till Insikt för att analysera information från enbart de utvalda områdena. En prototyp med önskad funktionalitet har under arbetets gång tagits fram, men för att ha en säljbar produkt är en del arbeta kvar. Prototypen har visats för ett antal intresserade som tyckte det var intressant och tror att det är något som skulle kunna användas flitigt inom många områden.
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Britain and France adapted two different integration models, namely assimilationist and multiculturalism to integrate their immigrants. These two big models of integration have distinctive characteristics to integrate immigrants. There is a general claim that multiculturalism model is the best for integrating immigrants in terms of actual integration, however, some argue the opposite, that French assimilationist model is ‘better off.’ This study examines these controversial claims by looking at the level to which immigrants are integrated in economic, social, political, cultural dimensions of integration and attitudes towards immigrants in Britain and France. Within a given theoretical framework, this study compares the overall competency level of immigrants’ integration in terms of actual integration between British multiculturalism model and French assimilationist model and validate that both these two big models of integration have reached a comparable level of integration and they do not have any decisive impact on actual integration.
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The client, Senselogic, had noticed an increased demand for an e-commerce system integrated into its product, SiteVision, something that did not previously exist. Senselogic wanted to integrate a third-party system to manage e-commerce. The problem was that there were very many e-commerce solutions to choose from. In order to select the best system it was necessary to evaluate the e-commerce systems and compare them to each other. To identify the elements that has to be included in an e-commerce system a study of literature was conducted. From the parts identified in the study of literature, a number of criteria were presented. Those criteria were then supplemented with additional criteria that Senselogic required of an e-commerce system before integrating it with SiteVision. Before the evaluation a number of test cases were created to test whether the ecommerce systems fulfilled to the criteria developed. These test cases were then used in the evaluation of the e-commerce systems while a test score was filled in. Then the evaluations of the different systems were compiled and compared in order to see which system best fulfilled the criteria. There was one system that scored higher than the others in the evaluation created. That was the system chosen to integrate with SiteVision.
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Today, there are no standardized ways to characterize SOA, many are talking about SOA and many say they are using SOA. One way that we have chosen to characterize this phenomenon is through an evaluation that will indicate whether SOA have been used in the development. Basedon a Service Oriented Architecture literature study, we have created an evaluation pattern resulting SOA principles of integration, architecture and services. This evaluation was applied to Logica's own integration system AgrCom through an empirical study to result in a response indicating whether AgrCom is SOA based. The results of the evaluation show that AgrCom is part of an SOA solution but not an SOA as a whole concept. The study shows that it takes morethan just systems in an activity to be referred to as the SOA-based, hence the architecture of anactivity must be taken into account.
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The present paper examines building integrated solar collectors with absorbers of polymeric materials. Efficiency measurements of façade-integrated collectors with non-selective black and spectrally selective coloured absorbers are carried out. The performance of the polymeric absorber was compared with solar glass and polycarbonate twin-wall sheets as collector cover. Simulations demonstrate a high solar fraction for a solar combisystem with façade collectors for a well-insulated house in a Nordic climate. Two examples of house concepts with façade collectors are presented which address a new type of customer than the solar enthusiasts with special interest in renewable energy