926 resultados para Structural Diversity of Antimicrobial Peptides
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Human exploitation of the forest in the northwest of São Paulo State has generated enormous fragmentation of that forest. Such disturbance has reduced the populations of insects in general. This work was a survey of social wasps (Hymenoptera, Vespidae; Polistinae) in three areas in different stages of regeneration: Paulo de Faria - SP (435 ha), Pindorama - SP (128 ha) and Neves Paulista - SP (1 ha). These three areas were chosen for comparative purposes. To capture the wasps, it was used: active collecting with attractant liquid (solution of water, salt and sugar) with the aid of a dorsal spray bag. During the period from July to December 2006, 414 social wasps were collected in Paulo de Faria, constituting seven species belonging to four genera; 111 social wasps were collected in Pindorama, constituting six species belonging to four genera, and 129 social wasps were collected in Neves Paulista constituting 12 species belonging to seven genera. In order to compare these three areas ecological indexes were calculated. Neves Paulista had the greatest diversity, and Paulo de Faria presented greater abundance. These factors were probably caused by neighboring areas and ecological corridors, which were limited in Paulo de Faria and Pindorama.
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We examine the dynamics of US output and inflation using a structural time varyingcoefficient VAR. We show that there are changes in the volatility of both variables andin the persistence of inflation. Technology shocks explain changes in output volatility,while a combination of technology, demand and monetary shocks explain variations inthe persistence and volatility of inflation. We detect changes over time in the transmission of technology shocks and in the variance of technology and of monetary policyshocks. Hours and labor productivity always increase in response to technology shocks.
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We examine the dynamics of output growth and inflation in the US, Euro area and UK using a structural time varying coefficient VAR. There are important similarities in structural inflation dynamics across countries; output growth dynamics differ. Swings in the magnitude of inflation and output growth volatilities and persistences are accounted for by a combination of three structural shocks. Changes over time in the structure of the economy are limited and permanent variations largely absent. Changes in the volatilities of structural shocks matter.
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Diversity of Odonata (Insecta) in lotic systems from Serra da Bodoquena, Mato Grosso do Sul State, Brazil. A systematic survey was carried out in four lotic systems from Serra da Bodoquena, the largest natural forests of the State, from August 2007 to November 2008. 548 specimens belonging to 33 species, distributed in 5 families were sampled. Libellulidae was dominant, with 13 species, followed by Gomphidae, Coenagrionidae, Protoneuridae and Calopterygidae.
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Diversity of the euglossine bee community (Hymenoptera, Apidae) of an Atlantic Forest remnant in southeastern Brazil. Euglossine bees, attracted to scent baits of cineole, eugenol and vanillin, were collected with entomological nets, from December 1998 to November 1999. Samplings were carried out once a month simultaneously by two collectors positioned in two different sites in an Atlantic Forest remnant in northeastern São Paulo state, Brazil. A total of 859 male euglossine bees, belonging to 13 species and four Euglossini genera were collected. Of the total sample, 506 (12 species) males were captured at site A and 353 (10 species) were collected at site B.In both sites, Euglossa pleosticta Dressler, 1982 was the most abundant species (45.79%), followed by Eulaema nigrita Lepeletier, 1841 (20.79%). The results of this study supply new information about the diversity of orchid bee fauna in Atlantic Forest remnants as well as show that more than one site is needed to sample these bees in a fragmented landascape.
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INTRODUCTION: Interindividual variations in regional structural properties covary across the brain, thus forming networks that change as a result of aging and accompanying neurological conditions. The alterations of superficial white matter (SWM) in Alzheimer's disease (AD) are of special interest, since they follow the AD-specific pattern characterized by the strongest neurodegeneration of the medial temporal lobe and association cortices. METHODS: Here, we present an SWM network analysis in comparison with SWM topography based on the myelin content quantified with magnetization transfer ratio (MTR) for 39 areas in each hemisphere in 15 AD patients and 15 controls. The networks are represented by graphs, in which nodes correspond to the areas, and edges denote statistical associations between them. RESULTS: In both groups, the networks were characterized by asymmetrically distributed edges (predominantly in the left hemisphere). The AD-related differences were also leftward. The edges lost due to AD tended to connect nodes in the temporal lobe to other lobes or nodes within or between the latter lobes. The newly gained edges were mostly confined to the temporal and paralimbic regions, which manifest demyelination of SWM already in mild AD. CONCLUSION: This pattern suggests that the AD pathological process coordinates SWM demyelination in the temporal and paralimbic regions, but not elsewhere. A comparison of the MTR maps with MTR-based networks shows that although, in general, the changes in network architecture in AD recapitulate the topography of (de)myelination, some aspects of structural covariance (including the interhemispheric asymmetry of networks) have no immediate reflection in the myelination pattern.
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Diversity of Calliphoridae and Sarcophagidae (Diptera, Oestroidea) in continuous forest and gaps at different stages of regeneration in the Urucu oilfield in western Brazilian Amazonia. The diversity of Calliphoridae and Sarcophagidae in continuous forest and gaps at different stages of regeneration was studied in the Urucu river basin, in Coari, state of Amazonas, Brazil. The flies were collected at 16 sampling points, 12 in gaps at different stages of regeneration (early _ C1, mid- C2 and late successional _ C3) and four in continuous forest _ MT. The diversity of blowflies was similar in the two less regenerated habitats (C1 and C2), and lower than that in the late successional (C3) and continuous forests (MT). By contrast, the diversity of flesh flies was much higher in all three types of gaps (C1, C2 and C3) in comparison with continuous forest (MT). Ordination (NMDS) and similarity (ANOSIM) analyses revealed that the blowflies communities were grouped by habitat type, which affected species composition more than diversity. Analysis of the flesh flies revealed two main groupings, gaps (C1, C2 and C3) and continuous forest (MT), with no evidence of any influence of successional stage on the diversity of the community.
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Polistine wasps are important in Neotropical ecosystems due to their ubiquity and diversity. Inventories have not adequately considered spatial attributes of collected specimens. Spatial data on biodiversity are important for study and mitigation of anthropogenic impacts over natural ecosystems and for protecting species. We described and analyzed local-scale spatial patterns of collecting records of wasp species, as well as spatial variation of diversity descriptors in a 2500-hectare area of an Amazon forest in Brazil. Rare species comprised the largest fraction of the fauna. Close range spatial effects were detected for most of the more common species, with clustering of presence-data at short distances. Larger spatial lag effects could also be identified in some species, constituting probably cases of exogenous autocorrelation and candidates for explanations based on environmental factors. In a few cases, significant or near significant correlations were found between five species (of Agelaia, Angiopolybia, and Mischocyttarus) and three studied environmental variables: distance to nearest stream, terrain altitude, and the type of forest canopy. However, association between these factors and biodiversity variables were generally low. When used as predictors of polistine richness in a linear multiple regression, only the coefficient for the forest canopy variable resulted significant. Some level of prediction of wasp diversity variables can be attained based on environmental variables, especially vegetation structure. Large-scale landscape and regional studies should be scheduled to address this issue.
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Braconidae is a highly diversified family of Hymenoptera and usually known by their role in biological control both in agricultural and natural ecosystems. Despite of that, little is known about its diversity in the Amazon region. The present work inventoried the braconid fauna of an Open Ombrophylous Forest with Palm Trees of the Parque Natural Municipal de Porto Velho, RO. Insects were collect from June/2008 to May/2009 using six Malaise traps in different parts of the reserve. A total of 377 wasps were captured, 17 subfamilies and 56 genera identified. Braconinae, Microgastrinae, Doryctinae and Rogadinae subfamilies were very abundant, and also the genera Aleiodes, Bracon, Capitonius, Compsobracon, Heterospilus, Hymenochaonia, Opius, Pedinotus, Rogas and Stantonia. The calculated Shannon diversity index was 2.15 and 3.3 for subfamily and genera, respectively, which were, generally, higher than the values found for other regions in Brazil. Generally, parasitoids were more abundant during the rainy season. The present work contributes with new genera records and faunistic data of Braconidae in Rondonia State, western Amazon.
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The aim of this study was to inventory the mayfly fauna, based on nymphal and alate stages, in Serra da Mantiqueira and in Serra do Mar, São Paulo State, as well as to present information about habitats used by the genera. Nymphs were collected in several streams and mesohabitats with a Surber sampler and the winged stages with light attraction methods, entomological nets, and Malaise traps. In all, eight families and 33 genera were recorded, representing a very significant portion of the Brazilian fauna (80% of families and 49% of genera). Furthermore, it was possible to identify 11 species, of which two are new records for the state: Tricorythodes santarita Traver and Caenis reissi Malzacher. Despite the high diversity recorded, the accumulation curves presented an ascending form, indicating an increase in the number of genera with additional sampling effort. The high richness found in these areas are in agreement with the high biodiversity of the Atlantic Forest biome and the sampling effort employed, which included the use of different methods, the collection of both nymphs and winged stages, and the sampling of a large area with diverse streams and habitats.
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Comparative abundance and diversity of Dryininae (Hymenoptera, Dryinidae) in three savannah phytophysiognomies in southeastern Brazil, under three sampling methods. This study aimed to assess the abundance and diversity of Dryininae in riparian vegetation, Brazilian savannah, and savannah woodland vegetation at the Estação Ecológica de Jataí, in Luiz Antônio, State of São Paulo, Brazil, by using Moericke, Malaise, and light traps. The sampling was carried out from December 2006 to November 2009, and 371 specimens of Dryininae were caught, with the highest frequencies in spring and summer. Fourteen species of Dryinus Latreille, 1804 and one of Thaumatodryinus Perkins, 1905 were identified. The highest frequencies of Dryinus in the riparian vegetation differed significantly from those obtained in the Brazilian savannah and savannah woodland vegetation. In the riparian vegetation, the highest number of Dryinus was collected using light traps and the interactions between abundance and the collection method used were significant. The number of specimens of Dryinus collected in the Brazilian savannah and savannah woodland vegetation using Malaise traps did not differ significantly from those obtained using Moericke traps. Males significantly outnumbered females in the sex ratio of Dryinus. The species diversity of Dryinus based on females collected using Malaise traps was high in the Brazilian savannah. Furthermore, high species richness of female Dryinus was observed in riparian vegetation (six species) and Brazilian savannah (five). The light trap was the most successful method for sampling diversity of Dryininae.
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Human papillomavirus type 6 (HPV6) is the major etiological agent of anogenital warts and laryngeal papillomas and has been included in both the quadrivalent and nonavalent prophylactic HPV vaccines. This study investigated the global genomic diversity of HPV6, using 724 isolates and 190 complete genomes from six continents, and the association of HPV6 genomic variants with geographical location, anatomical site of infection/disease, and gender. Initially, a 2,800-bp E5a-E5b-L1-LCR fragment was sequenced from 492/530 (92.8%) HPV6-positive samples collected for this study. Among them, 130 exhibited at least one single nucleotide polymorphism (SNP), indel, or amino acid change in the E5a-E5b-L1-LCR fragment and were sequenced in full. A global alignment and maximum likelihood tree of 190 complete HPV6 genomes (130 fully sequenced in this study and 60 obtained from sequence repositories) revealed two variant lineages, A and B, and five B sublineages: B1, B2, B3, B4, and B5. HPV6 (sub)lineage-specific SNPs and a 960-bp representative region for whole-genome-based phylogenetic clustering within the L2 open reading frame were identified. Multivariate logistic regression analysis revealed that lineage B predominated globally. Sublineage B3 was more common in Africa and North and South America, and lineage A was more common in Asia. Sublineages B1 and B3 were associated with anogenital infections, indicating a potential lesion-specific predilection of some HPV6 sublineages. Females had higher odds for infection with sublineage B3 than males. In conclusion, a global HPV6 phylogenetic analysis revealed the existence of two variant lineages and five sublineages, showing some degree of ethnogeographic, gender, and/or disease predilection in their distribution. IMPORTANCE: This study established the largest database of globally circulating HPV6 genomic variants and contributed a total of 130 new, complete HPV6 genome sequences to available sequence repositories. Two HPV6 variant lineages and five sublineages were identified and showed some degree of association with geographical location, anatomical site of infection/disease, and/or gender. We additionally identified several HPV6 lineage- and sublineage-specific SNPs to facilitate the identification of HPV6 variants and determined a representative region within the L2 gene that is suitable for HPV6 whole-genome-based phylogenetic analysis. This study complements and significantly expands the current knowledge of HPV6 genetic diversity and forms a comprehensive basis for future epidemiological, evolutionary, functional, pathogenicity, vaccination, and molecular assay development studies.
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Many root-colonizing pseudomonads are able to promote plant growth by increasing phosphate availability in soil through solubilization of poorly soluble rock phosphates. The major mechanism of phosphate solubilization by pseudomonads is the secretion of gluconic acid, which requires the enzyme glucose dehydrogenase and its cofactor pyrroloquinoline quinone (PQQ). The main aim of this study was to evaluate whether a PQQ biosynthetic gene is suitable to study the phylogeny of phosphate-solubilizing pseudomonads. To this end, two new primers, which specifically amplify the pqqC gene of the Pseudomonas genus, were designed. pqqC fragments were amplified and sequenced from a Pseudomonas strain collection and from a natural wheat rhizosphere population using cultivation-dependent and cultivation-independent approaches. Phylogenetic trees based on pqqC sequences were compared to trees obtained with the two concatenated housekeeping genes rpoD and gyrB. For both pqqC and rpoD-gyrB, similar main phylogenetic clusters were found. However, in the pqqC but not in the rpoD-gyrB tree, the group of fluorescent pseudomonads producing the antifungal compounds 2,4-diacetylphloroglucinol and pyoluteorin was located outside the Pseudomonas fluorescens group. pqqC sequences from isolated pseudomonads were differently distributed among the identified phylogenetic groups than pqqC sequences derived from the cultivation-independent approach. Comparing pqqC phylogeny and phosphate solubilization activity, we identified one phylogenetic group with high solubilization activity. In summary, we demonstrate that the gene pqqC is a novel molecular marker that can be used complementary to housekeeping genes for studying the diversity and evolution of plant-beneficial pseudomonads.
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Maghemite (γFe2O3) from tuffite is exceptionally rich in Mg, relatively to most of those reportedly found in other mafic lithosystems. To investigate in detail the compositional and structural variabilities of this natural magnetic iron oxide, sets of crystals were isolated from samples collected at different positions in a tuffite weathering mantle. These sets of crystal were individually powdered and studied by X-ray diffractometry, Mössbauer spectroscopy, magnetization measurements and chemical analysis. Lattice parameter of the cubic cell (a0) was found to vary from 0.834(1) to 0.8412(1) nm. Lower a0-values are characteristic of maghemite whereas higher ones are related to a magnetite precursor. FeO content ranges up to 17 mass % and spontaneous magnetization ranges from 8 to 32 J T-1 kg-1. Zero-field room temperature Mössbauer spectra are rather complex, indicating that the hyperfine field distributions due to Fe3+ and mixed valence Fe3+/2+ overlap. The structural variabilities of the (Mg, Ti)-rich iron oxide spinels is essentially related to the range of chemical composition of its precursor (Mg, Ti)-rich magnetite, and probably to the extent to which it has been oxidized during transformation in soil.