522 research outputs found

    Molecular evidence for the occurrence of a new sibling species within the Anopheles (Kerteszia) cruzii complex in south-east Brazil

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    <p>Abstract</p> <p>Background</p> <p><it>Anopheles cruzii </it>(Diptera: Culicidae) has long been known as a vector of human and simian malaria parasites in southern and south-eastern Brazil. Previous studies have provided evidence that <it>An. cruzii </it>is a species complex, but the status of the different populations and the number of sibling species remains unclear. A recent analysis of the genetic differentiation of the <it>timeless </it>gene among <it>An. cruzii </it>populations from south and south-east Brazil has suggested that the population from Itatiaia, Rio de Janeiro State (south-east Brazil), is in a process of incipient speciation.</p> <p>Methods</p> <p>A ~180 bp fragment of <it>cpr</it>, a gene encoding the NADPH-cytochrome P450 reductase, an enzyme involved in metabolic insecticide resistance and odorant clearance in insects, was used in this study as a molecular marker to analyse the divergence between five <it>An. cruzii </it>populations from south and south-east Brazil.</p> <p>Results</p> <p>Analysis of the genetic differentiation in the <it>cpr </it>gene revealed very high <it>F<sub>ST </sub></it>values and fixed differences between Itatiaia and the other four populations studied (Florianópolis, Cananéia, Juquitiba and Santa Teresa). In addition, the data also provided preliminary evidence that seems to indicate the occurrence of two sympatric sibling species in Itatiaia.</p> <p>Conclusions</p> <p>Population genetics analysis of <it>An. cruzii </it>samples from different localities using a fragment of the <it>cpr </it>gene suggests that the Itatiaia sample represents at least one new sibling species in this complex.</p

    Site-condition map for Portugal based on Vs30 values and evaluation of the applicability of Vs30 proxies

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    Maps providing information on site conditions are essential tools to accurately represent the spatial distribution of ground motions, both in seismic hazard maps and in instrumental intensity maps (ShakeMaps). Project SCENE, funded by the Portuguese Foundation for Science and Technology, aims at characterizing the site conditions for Portugal and to outline a first-order site effects map to be used in seismic hazard assessment at a national level. In the context of project SCENE we developed a database of available shear-wave velocity profiles to- gether with surface-geology data and geotechnical data. Currently the database includes around 60 profiles dispersed in a variety of lithological and geological units. The vast majority of data consist of seismic refraction sections that were acquired both within the scope of ongoing research projects SCENE and NEFITAG, and previously performed CAPSA and ERSTA campaigns. Few sites analyzed with multichannel analysis of surface waves by Lopes et al. (2005) were also included. The Vs30 values calculated from the profiles range from 100 m/s to1000 m/s, but the higher values are poorly represented. We performed a careful evaluation of the geological conditions at database sites, using the smallest scale available maps (usually 1:50000), and grouped it into six generalized geological units. The variability of the distribution of Vs30 values varies significantly with the generalized geological unit. Holocene deposits and Pliocene units display the lowest variance. On the other hand the Pleistocene and Miocene units, which are characterized in Portugal by a large lithological variety, display a large dispersion. Geological outcrop studies and the analysis of geotechnical data in close association the seismic refraction data acquisition are currently under way to better understand this velocity-lithology relation. The use of proxies based either on exogenous geological-geographical defined units (Wills et al., 2006) or topographic slope shows relatively unbiased residual distributions of the logarithm of Vs30. Although the variance is large for both methods the geological/geographical-defined units method shows a better performance with respect to the topographic slope method. Lemoine et al. (2012) evaluated the applicability of the topographic slope method for stable and active re- gions of Europe using the Vs30 dataset compiled in the context of project SHARE. The variability of the entire residuals distribution is larger for the Portuguese dataset than for the European dataset, suggesting that the European database is far from being representative of the near-surface conditions in Europe

    Earthquake Mitigation in the Lisbon and Lower Tagus Valley area, Portugal

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    The capital city of Lisbon and the Lower Tagus Valley region of central Portugal mainland are located in the Eurasian plate about 350 Km from the approximately E-W oriented Eurasia-Africa plate boundary. It is characterized by low slip-rates (<0.4 mm/year) and a moderate seismicity, occasionally shaken by some important historical earthquakes causing significant damages and economical losses. The most well know damaging earthquakes occurred in 1344, 1531, 1755, 1909 and 1969. The seismic hazard evaluation and mitigation of the area is therefore of great importance to this densely populated area. This paper focuses the evaluation of P- wave and S-wave seismic velocities of the shallowest surface using seismic refraction data interpretation and in- situ lithostratigraphic studies to obtain geotechnical parameters such as Vp/Vs ratios and the Poisson coefficient, estimated to provide information for future site effect studies and preliminary VS30 and soil classification maps. The information will also be used to correct earthquake records since this information was also collected close to the location of seismological stations. The soil classification is based upon the European Code 8 for civil engineering which was carried out for land use planning and design of critical facilities. Hundreds of available boreholes drilled for engineering (with SPT data) and water supply were used to confirm layer thicknesses and lithologies at depth together with a detailed geological survey of each profile area. It is the first time VS30 maps and a soil classification based on geophysical and geotechnical parameters is attempted for this highly populated region

    Assessing the molecular divergence between Anopheles (Kerteszia) cruzii populations from Brazil using the timeless gene: further evidence of a species complex

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    Submitted by Sandra Infurna ([email protected]) on 2019-01-15T13:43:46Z No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-01-15T13:52:05Z (GMT) No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5)Made available in DSpace on 2019-01-15T13:52:05Z (GMT). No. of bitstreams: 1 luisaDp_rona_etal_IOC_2009.pdf: 651215 bytes, checksum: 4fc0bfe6cd7738120844230e1013d041 (MD5) Previous issue date: 2009Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil.Universidade Federal de Santa Catarina. Departamento de Microbiologia, Imunologia e Parasitologia. Florianópolis, SC, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil / Queen Mary University of London. School of Biological and Chemical Sciences. London, UK.Universidade Federal de Santa Catarina. Departamento de Microbiologia, Imunologia e Parasitologia. Florianópolis, SC, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Biologia Molecular de Insetos. Rio de Janeiro, RJ. Brasil.Background: Anopheles (Kerteszia) cruzii was the most important vector of human malaria in southern Brazil between 1930–1960. Nowadays it is still considered an important Plasmodium spp. vector in southern and south-eastern Brazil, incriminated for oligosymptomatic malaria. Previous studies based on the analysis of X chromosome banding patterns and inversion frequencies in An. cruzii populations from these areas have suggested the occurrence of three sibling species. In contrast, two genetically distinct groups among An. cruzii populations from south/south-east and north-east Brazil have been revealed by isoenzyme analysis. Therefore, An. cruzii remains unclear

    Population Biology of Rhodnius domesticus Neiva & Pinto, 1923 (Hemiptera: Reduviidae) under Laboratory Conditions

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    The entire life cycle of Rhodnius domesticus, fed weekly on mice, was studied under controlled conditions. Aspects related to hatching, life time, mortality, feeding behaviour and fecundity for each stage of the insect life-cycle were evaluated. The hatching rate observed in 100 eggs was 57% and the mean time of hatching was 15.6 days. Forty-six nymphs (80.7%) completed the cycle and the mean time from NI to adult was 93.8 days. The average span in days for each stage was 12.4 for NI, 9.8 for NII, 14.2 for NIII, 16.8 for NIV and 25.0 for NV. The number of bloodmeals in each nymphal stage varied from 1 to 3. The mortality rate was 12.3% for NI, 3.5% for NII and 1.7% for NIII and NV nymphs. The mean number of eggs laid per female in a 9-month period was 333.1. Average adult survival rates were 287.6 +133 and 328 +73 days for males and females respectively

    Lean Safety - assessment of the impact of 5S and Visual Management on safety

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    This study was developed in a furniture company and aimed to implement some Lean tools, such as 5S and Visual Management to reduce waste, by improving the production process. To carry out this analysis an observation plan was used, having the Spaghetti diagram as a reference as well as the value-added analysis of the operations. The implementation of 5S's allowed the improvement of the visual management and the organization through a reorganization of the layout, as well as normalization of the production process. With this, a reduction of 40% was achieved in terms of waste related to activities that did not add value to the product, such as unnecessary movements, waiting times and even movement of materials, having achieved a level of productivity of 74% and 87% in the finishing and joinery sections, respectively. In addition to improvements in the production process, the impact of the measures at the safety level (lean safety) was assessed. For this purpose, a questionnaire was prepared to assess the opinion of the employees, in which 40% considered that the implementation of the tools provided a greater motivation to develop their work activities safelyinfo:eu-repo/semantics/publishedVersio

    Ingestive Behaviour of Steers in Native Pastures in Southern Brazil

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    The Campos biome, particularly its native pastures, is the main resource for livestock production in southern Brazil (Boldrini, 1997). It has a huge floristic diversity in which more than 400 grass and 150 legume species are found. These pastures are very heterogeneous with horizontal as well as vertical structure. Hodgson (1985) stressed the importance of sward structure upon diet selection, emphasizing the difficulties animals could have to access all pasture layers in temperate pastures. This experiment investigates how variation in herbage allowance along the growing season influences the ingestive behaviour of steers
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