866 research outputs found
Upper mantle anisotropy of the Borborema Province, NE Brazil: Implications for intra-plate deformation and sub-cratonic asthenospheric flow
Speed Partitioning for Indexing Moving Objects
Indexing moving objects has been extensively studied in the past decades.
Moving objects, such as vehicles and mobile device users, usually exhibit some
patterns on their velocities, which can be utilized for velocity-based
partitioning to improve performance of the indexes. Existing velocity-based
partitioning techniques rely on some kinds of heuristics rather than
analytically calculate the optimal solution. In this paper, we propose a novel
speed partitioning technique based on a formal analysis over speed values of
the moving objects. We first show that speed partitioning will significantly
reduce the search space expansion which has direct impacts on query performance
of the indexes. Next we formulate the optimal speed partitioning problem based
on search space expansion analysis and then compute the optimal solution using
dynamic programming. We then build the partitioned indexing system where
queries are duplicated and processed in each index partition. Extensive
experiments demonstrate that our method dramatically improves the performance
of indexes for moving objects and outperforms other state-of-the-art
velocity-based partitioning approaches
Detection of Brazilian spotted fever infection by polymerase chain reaction in a patient from the state of Sao Paulo
Brazilian spotted fever (BSF) cases have been increasing in the state of Sao Paulo but no genomic information about local rickettsia isolated from humans has been well documented. We recovered spotted-fever group rickett-siae from a sample of patient blood cultured in Vero cells using the shell vial technique. Rickettsial DNA fragments (gltA, ompA, and, ompB genes) were detected, and analysis of the ompB gene base sequences showed identity with the Rickettsia rickettsii ompB sequence available in the GenBank.100327727
Host Plant Record for the Fruit Flies, Anastrepha fumipennis and A. nascimentoi (Diptera, Tephritidae)
The first host plant record for Anastrepha fumipennis Lima (Diptera: Tephritidae) in Geissospermum laeve (Vell.) Baill (Apocynaceae) and for A. nascimentoi Zucchi found in Cathedra bahiensis Sleumer (Olacaceae) was determined in a host plant survey of fruit flies undertaken at the “Reserva Natural da Companhia Vale do Rio Doce”. This reserve is located in an Atlantic Rain Forest remnant area, in Linhares county, state of Espírito Santo, Brazil. The phylogenetic relationships of Anastrepha species and their hosts are discussed. The occurrence of these fruit fly species in relation to the distribution range of their host plants is also discussed
Release of Lungworm Larvae from Snails in the Environment: Potential for Alternative Transmission Pathways
Background: Gastropod-borne parasites may cause debilitating clinical conditions in animals and humans following the consumption of infected intermediate or paratenic hosts. However, the ingestion of fresh vegetables contaminated by snail mucus and/or water has also been proposed as a source of the infection for some zoonotic metastrongyloids (e.g., Angiostrongylus cantonensis). In the meantime, the feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior are increasingly spreading among cat populations, along with their gastropod intermediate hosts. The aim of this study was to assess the potential of alternative transmission pathways for A. abstrusus and T. brevior L3 via the mucus of infected Helix aspersa snails and the water where gastropods died. In addition, the histological examination of snail specimens provided information on the larval localization and inflammatory reactions in the intermediate host.
Methodology/Principal Findings: Twenty-four specimens of H. aspersa received ~500 L1 of A. abstrusus and T. brevior, and were assigned to six study groups. Snails were subjected to different mechanical and chemical stimuli throughout 20 days in order to elicit the production of mucus. At the end of the study, gastropods were submerged in tap water and the sediment was observed for lungworm larvae for three consecutive days. Finally, snails were artificially digested and recovered larvae were counted and morphologically and molecularly identified. The anatomical localization of A. abstrusus and T. brevior larvae within snail tissues was investigated by histology. L3 were detected in the snail mucus (i.e., 37 A. abstrusus and 19 T. brevior) and in the sediment of submerged specimens (172 A. abstrusus and 39 T. brevior). Following the artificial digestion of H. aspersa snails, a mean number of 127.8 A. abstrusus and 60.3 T. brevior larvae were recovered. The number of snail sections positive for A. abstrusus was higher than those for T. brevior.
Conclusions: Results of this study indicate that A. abstrusus and T. brevior infective L3 are shed in the mucus of H. aspersa or in water where infected gastropods had died submerged. Both elimination pathways may represent alternative route(s) of environmental contamination and source of the infection for these nematodes under field conditions and may significantly affect the epidemiology of feline lungworms. Considering that snails may act as intermediate hosts for other metastrongyloid species, the environmental contamination by mucus-released larvae is discussed in a broader context
Skin reactions to thimerosal and Leishmania in dogs from a leishmaniasis endemic area: it is better to keep them apart
Development and Validation of a Real-Time PCR for Detection of Pathogenic Leptospira Species in Clinical Materials
Available serological diagnostics do not allow the confirmation of clinically suspected leptospirosis at the early acute phase of illness. Several conventional and real-time PCRs for the early diagnosis of leptospirosis have been described but these have been incompletely evaluated. We developed a SYBR Green-based real-time PCR targeting secY and validated it according to international guidelines. To determine the analytical specificity, DNA from 56 Leptospira strains belonging to pathogenic, non-pathogenic and intermediate Leptospira spp. as well as 46 other micro-organisms was included in this study. All the pathogenic Leptospira gave a positive reaction. We found no cross-reaction with saprophytic Leptospira and other micro-organisms, implying a high analytical specificity. The analytical sensitivity of the PCR was one copy per reaction from cultured homologous strain M 20 and 1.2 and 1.5 copy for heterologous strains 1342 K and Sarmin, respectively. In spiked serum & blood and kidney tissue the sensitivity was 10 and 20 copies for M 20, 15 and 30 copies for 1342 K and 30 and 50 copies for Sarmin. To determine the diagnostic sensitivity (DSe) and specificity (DSp), clinical blood samples from 26 laboratory-confirmed and 107 negative patients suspected of leptospirosis were enrolled as a prospective consecutive cohort. Based on culture as the gold standard, we found a DSe and DSp of 100% and 93%, respectively. All eight PCR positive samples that had a negative culture seroconverted later on, implying a higher actual DSp. When using culture and serology as the gold standard, the DSe was lower (89%) while the DSp was higher (100%). DSe was 100% in samples collected within the first – for treatment important - 4 days after onset of the illness. Reproducibility and repeatability of the assay, determined by blind testing kidney samples from 20 confirmed positive and 20 negative rodents both appeared 100%. In conclusion we have described for the first time the development of a robust SYBR Green real-time PCR for the detection of pathogenic Leptospira combined with a detailed assessment of its clinical accuracy, thus providing a method for the early diagnosis of leptospirosis with a well-defined satisfactory performance
Dietary availability patterns of the brazilian macro-regions
<p>Abstract</p> <p>Introduction</p> <p>Epidemiological studies have raised concerns about the role of dietary patterns on the risk of chronic diseases and also in the formulation of better informed nutrition policies.</p> <p>Objective</p> <p>The development of a dietary availability patterns according to geographic regions in Brazil.</p> <p>Methodology</p> <p>The 2002-2003 Brazilian Household Budget Survey was conducted in 48,470 households. Dietary availability patterns were identified by Principal Component Analysis using as a unit of analysis the survey's Primary Sampling Units (PSUs) and purchased amounts for 21 food groups. Each of the extracted dietary availability patterns was regressed on socioeconomics categories.</p> <p>Results</p> <p>There were no differences in dietary availability patterns between urban and rural areas. In all regions, a rice and beans pattern was identified. This pattern explained 15% to 28% of the variance dependent on the region of the country. In South, Southeast and Midwest regions, a mixed pattern including at least 10 food groups explaining 8% to 16% of the variance. In the North region (Amazon forest included) the first pattern was based on fish and nuts and then it was designed as regional pattern. In multiple linear regression the rice and beans pattern was associated with the presence of adolescents in the households, except for North region, whereas the presence of adolescents was associated with the Regional pattern. A mixed patterns were associated with a higher income and education (p < 0.05), except in the South region.</p> <p>Conclusion</p> <p>The rice and beans and regional dietary availability patterns, both considered healthy eating patterns are still important in the country. Brazil has taken many actions to improve nutrition as part of their public health policies, the data of the Household Budget Survey could help to recognize the different food choices in the large regions of the country.</p
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