997 resultados para B. Tuberculata


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As moscas-brancas são pragas tanto de plantas ornamentais como de cultivos, sendo encontradas em quase todas as regiões onde se cultiva a mandioca. Nessa cultura, já foram identificadas as espécies Aleurotrachelus socialis, Aleurodicus dispersus, Aleurothrixus aepim, Aleuronudus sp., Bemisia tabaci, B. tuberculata, B. afer, Paraleyrodes sp., Trialeurodes abutilonea, T. variabilis e Tetraleurodes sp. Esses pequenos insetos são facilmente reconhecíveis, visto que em geral as populações dos adultos podem ser detectadas sacudindo os brotos das plantas para fazê-los voar, enquanto a fase jovem pode ser encontrada na face inferior das folhas basais e medianas.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This paper has three primary aims: to establish an effective means for modelling mainland-island metapopulations inhabiting a dynamic landscape: to investigate the effect of immigration and dynamic changes in habitat on metapopulation patch occupancy dynamics; and to illustrate the implications of our results for decision-making and population management. We first extend the mainland-island metapopulation model of Alonso and McKane [Bull. Math. Biol. 64:913-958,2002] to incorporate a dynamic landscape. It is shown, for both the static and the dynamic landscape models, that a suitably scaled version of the process converges to a unique deterministic model as the size of the system becomes large. We also establish that. under quite general conditions, the density of occupied patches, and the densities of suitable and occupied patches, for the respective models, have approximate normal distributions. Our results not only provide us with estimates for the means and variances that are valid at all stages in the evolution of the population, but also provide a tool for fitting the models to real metapopulations. We discuss the effect of immigration and habitat dynamics on metapopulations, showing that mainland-like patches heavily influence metapopulation persistence, and we argue for adopting measures to increase connectivity between this large patch and the other island-like patches. We illustrate our results with specific reference to examples of populations of butterfly and the grasshopper Bryodema tuberculata.

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Als erste komplette Sequenz eines Gastropoden-Hämocyanins wurde das Hämocyanin von Haliotis tuberculata über cDNA vollständig kloniert und sequenziert. Die Primärstruktur besteht aus 3404 Aminosäuren mit einer errechneten Molekülmasse von 392 kDa. Neben der vollständigen Primärstruktur des sezernierten Proteins ist in der cDNA eine Signalsequenz kodiert. Mit Hilfe spezifischer Primer wurde die Genstruktur des HtH1-Gens zwischen der Signalsequenz und dem 3´-UTR über PCR aus genomischer DNA ermittelt. Dies ist die erste bekannte Genstruktur eines Schnecken-Hämocyanins. Das Gen umfaßt etwa 28,6 kb und besteht aus 17 Exons und 16 Introns. Die kodierende Sequenz des Signalpeptids und der acht FUs sind in den Linker-Regionen durch Introns (Linker-Introns) getrennt. Die Signalsequenz von bislang 48 Nukleotiden sowie die Sequenz der funktionellen Domänen HtH1-a, HtH1-f und HtH1-g sind durch 'interne' Introns in zwei bis vier Exons unterteilt. Von der Untereinheit HtH2 wurde über cDNA und genomische PCR die vollständige kodierende Sequenz der funktionellen Domänen HtH2-b bis HtH2-h und ein großer Teil von HtH2-a sequenziert. Die partielle Primärstruktur umfaßt 3307 Aminosäuren. Es fehlen noch etwa 100 Aminosäuren aus dem N-terminalen Bereich von HtH2-a. Das Fragment des HtH2-Gens von 18,3 kb besteht aus 15 Exons und 14 Introns. Die Exon-Größen und die Positionen sowie Phasen der Introns entsprechen exakt den Verhältnissen im HtH1-Gen. Multiple Sequenzalignments und daraus erstellte phylogenetische Stamm¤ume mit den abgeleiteten Aminosäuresequenzen von HtH1, HtH2 und anderen Mollusken-Hämocyaninen zeigen die Verwandtschaftsverhältnisse der Mollusken-Hämocyanine. Auf der Annahme basierend, daß eine 'molekulare Uhr' existiert, läßt sich mit Hilfe einer Distanzmatrix die Phylogenie der Mollusken-Hämocyanine rekapitulieren und die einzelnen Aufspaltungsereignisse im Verlauf der Evolution der Mollusken datieren.

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The climatic deterioration related to the onset of Northern Hemisphere glaciations (circa 2.52 Ma BP) must have lead to reorganization and relocation of species associations and may have enhanced species turnover. The present study investigates how this deterioration affects the dinoflagellate cyst and acritarch assemblages from two locations, DSDP Site 607 (North Atlantic) and the Singa section (southern Italy). The records from these locations cover the interval from 2.8 to 2.2 Ma with at least a 5 ka resolution and they have been correlated to the Milankovitch periodicities on a cycle to cycle basis by means of integrated high resolution stable isotope, calcium carbonate, foraminiferal, palynological and magnetostratigraphical datasets. In the present study this high resolution stratigraphic framework is used for a detailed correlation of events occurring in each of the depositional sequences. It also enables further assessment of the palaeoenvironmental preferences of some dinoflagellate cyst forms. Comparison of the two palynological records reveals a close correspondence in the timing of major assemblage changes and extinction events, confirming their Milankovitch cycle based correlation. A close link between periods of Northern Hemisphere cooling (at oxygen isotope stages 110, 104 and 100-96) and increased dinoflagellate cyst turnover appears to be present for both DSDP Site 607 and the Singa section. The turnover events can also be recognized in the records of planktic foraminifera and calcamous nannoplankton. Comparison of the Singa section with Site 607 and with other time equivalent marine palynological data sets, shows that some oceanic taxa respond similarly over a large area. The biostratigraphical implications are discussed. Notably the last occurrence of Invertocystu lucrymosa appears to be a valuable marker for isotope stage 110 in the Mediterranean and North Atlantic.

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Aim: In the current climate of medical education, there is an ever-increasing demand for and emphasis on simulation as both a teaching and training tool. The objective of our study was to compare the realism and practicality of a number of artificial blood products that could be used for high-fidelity simulation. Method: A literature and internet search was performed and 15 artificial blood products were identified from a variety of sources. One product was excluded due to its potential toxicity risks. Five observers, blinded to the products, performed two assessments on each product using an evaluation tool with 14 predefined criteria including color, consistency, clotting, and staining potential to manikin skin and clothing. Each criterion was rated using a five-point Likert scale. The products were left for 24 hours, both refrigerated and at room temperature, and then reassessed. Statistical analysis was performed to identify the most suitable products, and both inter- and intra-rater variability were examined. Results: Three products scored consistently well with all five assessors, with one product in particular scoring well in almost every criterion. This highest-rated product had a mean rating of 3.6 of 5.0 (95% posterior Interval 3.4-3.7). Inter-rater variability was minor with average ratings varying from 3.0 to 3.4 between the highest and lowest scorer. Intrarater variability was negligible with good agreement between first and second rating as per weighted kappa scores (K = 0.67). Conclusion: The most realistic and practical form of artificial blood identified was a commercial product called KD151 Flowing Blood Syrup. It was found to be not only realistic in appearance but practical in terms of storage and stain removal.

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After many years of development BIM (Building Information Modelling) is starting to achieve significant penetration into the building sector of the construction industry. This paper describes the current status of BIM and the drivers that are motivating the change from 2D CAD to BIM within the building sector. The paper then discusses what the implications of the technology underlying BIM may be for the civil construction sector of the construction industry. A project carried out by the Cooperative Research Centre for Construction Innovation is used as an example of this technology as well as several international examples.

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The 1:1 proton-transfer compound of the potent substituted amphetamine hallucinogen (R)-1-(8-bromobenzo[1,2-b; 4,5-b']difuran-4-yl)-2-aminopropane (common trivial name 'bromodragonfly') with 3,5-dinitrosalicylic acid, 1-(8-bromobenzo[1,2-b;4,5-b']difuran-4-yl)-2-mmoniopropane 2-carboxy-4,6-dinitrophenolate, C13H13BrNO2+ C7H3N2O7- forms hydrogen-bonded cation-anion chain substructures comprising undulating head-to-tail anion chains formed through C(8) carboxyl O-H...O(nitro) associations and incorporating the aminium groups of the cations. The intra-chain cation-anion hydrogen-bonding associations feature proximal cyclic R33(8) interactions involving both a N+-H...O(phenolate) and the carboxyl O--H...O(nitro)associations. Also present are aromatic pi-pi ring interactions [minimum ring centroid separation, 3.566(2)A; inter-plane dihedral angle, 5.13(1)deg]. A lateral hydrogen-bonding interaction between the third aminium proton and a carboxyl O acceptor link the chain substructures giving a two-dimensional sheet structure. This determination represents the first of any form of this compound and confirms that it has the (R) absolute configuration. The atypical crystal stability is attributed both to the hydrogen-bonded chain substructures provided by the anions, which accommodate the aminium proton-donor groups of the cations and give cross-linking, and to the presence of cation--anion aromatic ring pi-pi interactions.