13 resultados para 7441-109

em Repositório da Produção Científica e Intelectual da Unicamp


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The arboreal ant Odontomachus hastatus nests among roots of epiphytic bromeliads in the sandy forest at Cardoso Island (Brazil). Crepuscular and nocturnal foragers travel up to 8m to search for arthropod prey in the canopy, where silhouettes of leaves and branches potentially provide directional information. We investigated the relevance of visual cues (canopy, horizon patterns) during navigation in O. hastatus. Laboratory experiments using a captive ant colony and a round foraging arena revealed that an artificial canopy pattern above the ants and horizon visual marks are effective orientation cues for homing O. hastatus. On the other hand, foragers that were only given a tridimensional landmark (cylinder) or chemical marks were unable to home correctly. Navigation by visual cues in O. hastatus is in accordance with other diurnal arboreal ants. Nocturnal luminosity (moon, stars) is apparently sufficient to produce contrasting silhouettes from the canopy and surrounding vegetation, thus providing orientation cues. Contrary to the plain floor of the round arena, chemical cues may be important for marking bifurcated arboreal routes. This experimental demonstration of the use of visual cues by a predominantly nocturnal arboreal ant provides important information for comparative studies on the evolution of spatial orientation behavior in ants. This article is part of a Special Issue entitled: Neotropical Behaviour.

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Envenoming by the pitviper Bothrops jararacussu produces cardiovascular alterations, including coagulopathy, systemic hemorrhage, hypotension, circulatory shock and renal failure. In this work, we examined the activity of this venom in rat isolated right atria. Incubation with venom (0.025, 0.05, 0.1 and 0.2mg/ml) caused concentration-dependent muscle contracture that was not reversed by washing. Muscle damage was seen histologically and confirmed by quantification of creatine kinase-MB (CK-MB) release. Heating and preincubation of venom with p-bromophenacyl bromide (a phospholipase A2 inhibitor) abolished the venom-induced contracture and muscle damage. In contrast, indomethacin, a non-selective inhibitor of cyclooxygenase, and verapamil, a voltage-gated Ca(2+) channel blocker, did not affect the responses to venom. Preincubation of venom with Bothrops or Bothrops/Crotalus antivenom or the addition of antivenom soon after venom attenuated the venom-induced changes in atrial function and tissue damage. These results indicate that B. jararacussu venom adversely affected rat atrial contractile activity and muscle organization through the action of venom PLA2; these venom-induced alterations were attenuated by antivenom.

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In the Amazon Region, there is a virtual absence of severe malaria and few fatal cases of naturally occurring Plasmodium falciparum infections; this presents an intriguing and underexplored area of research. In addition to the rapid access of infected persons to effective treatment, one cause of this phenomenon might be the recognition of cytoadherent variant proteins on the infected red blood cell (IRBC) surface, including the var gene encoded P. falciparum erythrocyte membrane protein 1. In order to establish a link between cytoadherence, IRBC surface antibody recognition and the presence or absence of malaria symptoms, we phenotype-selected four Amazonian P. falciparum isolates and the laboratory strain 3D7 for their cytoadherence to CD36 and ICAM1 expressed on CHO cells. We then mapped the dominantly expressed var transcripts and tested whether antibodies from symptomatic or asymptomatic infections showed a differential recognition of the IRBC surface. As controls, the 3D7 lineages expressing severe disease-associated phenotypes were used. We showed that there was no profound difference between the frequency and intensity of antibody recognition of the IRBC-exposed P. falciparum proteins in symptomatic vs. asymptomatic infections. The 3D7 lineages, which expressed severe malaria-associated phenotypes, were strongly recognised by most, but not all plasmas, meaning that the recognition of these phenotypes is frequent in asymptomatic carriers, but is not necessarily a prerequisite to staying free of symptoms.

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A rapid, sensitive and specific method for quantifying propylthiouracil in human plasma using methylthiouracil as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using an organic solvent (ethyl acetate). The extracts were analyzed by high performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS/MS) in negative mode (ES-). Chromatography was performed using a Phenomenex Gemini C18 5μm analytical column (4.6mm×150mm i.d.) and a mobile phase consisting of methanol/water/acetonitrile (40/40/20, v/v/v)+0.1% of formic acid. For propylthiouracil and I.S., the optimized parameters of the declustering potential, collision energy and collision exit potential were -60 (V), -26 (eV) and -5 (V), respectively. The method had a chromatographic run time of 2.5min and a linear calibration curve over the range 20-5000ng/mL. The limit of quantification was 20ng/mL. The stability tests indicated no significant degradation. This HPLC-MS/MS procedure was used to assess the bioequivalence of two propylthiouracil 100mg tablet formulations in healthy volunteers of both sexes in fasted and fed state. The geometric mean and 90% confidence interval CI of Test/Reference percent ratios were, without and with food, respectively: 109.28% (103.63-115.25%) and 115.60% (109.03-122.58%) for Cmax, 103.31% (100.74-105.96%) and 103.40% (101.03-105.84) for AUClast. This method offers advantages over those previously reported, in terms of both a simple liquid-liquid extraction without clean-up procedures, as well as a faster run time (2.5min). The LOQ of 20ng/mL is well suited for pharmacokinetic studies. The assay performance results indicate that the method is precise and accurate enough for the routine determination of the propylthiouracil in human plasma. The test formulation with and without food was bioequivalent to reference formulation. Food administration increased the Tmax and decreased the bioavailability (Cmax and AUC).

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In Brazil, malaria remains a disease of major epidemiological importance because of the high number of cases in the Amazonian Region. Plasmodium spp infections during pregnancy are a significant public health problem with substantial risks for the pregnant woman, the foetus and the newborn child. In Brazil, the control of malaria during pregnancy is primarily achieved by prompt and effective treatment of the acute episodes. Thus, to assure rapid diagnosis and treatment for pregnant women with malaria, one of the recommended strategy for low transmission areas by World Health Organization and as part of a strategy by the Ministry of Health, the National Malaria Control Program has focused on integrative measures with woman and reproductive health. Here, we discuss the approach for the prevention and management of malaria during pregnancy in Brazil over the last 10 years (2003-2012) using morbidity data from Malaria Health Information System. Improving the efficiency and quality of healthcare and education and the consolidation of prevention programmes will be challenges in the control of malaria during pregnancy in the next decade.

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Passiflora species are distributed throughout Latin America, and Brazil and Colombia serve as the centers of diversity for this genus. We performed cross-species amplification to evaluate 109 microsatellite loci in 14 Passiflora species and estimated the diversity and genetic structure of Passiflora cincinnata, Passiflora setaceae and Passiflora edulis. A total of 127 accessions, including 85 accessions of P. edulis, a commercial species, and 42 accessions of 13 wild species, were examined. The cross-species amplification was effective for obtaining microsatellite loci (average cross-amplification of 70%). The average number of alleles per locus (five) was relatively low, and the average diversity ranged from 0.52 in P. cincinnata to 0.32 in P. setacea. The Bayesian analyses indicated that the P. cincinnata and P. setacea accessions were distributed into two groups, and the P. edulis accessions were distributed into five groups. Private alleles were identified, and suggestions for core collections are presented. Further collections are necessary, and the information generated may be useful for breeding and conservation.

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This text offers some contributions to the debate on the changes proposed to the National Curricular Directives to reform secondary education in Brazil. In the first part, the political and economic scene is evaluated as the context which generated the last stage of reforms in the educational field in the 90s. It questions the option for a model of structural reform (in the Brazilian case more restricted to the Program for Reform of Professional Education - PROEP) and of the curriculum, whose themes find their justification in the contemporary economic, social cultural and political context. It discusses the use of a model that bases itself on experiences developed in other countries and takes the international orientation of the multilateral organizations as its theoretical methodological reference, leaving out the peculiarities and injunctions of the Brazilian political administrative system. Such a policy measure can increase the tension and distance normally existing between government programs and the possibility of their real implementation in the school network. In the second part, it discusses the Resolution of the National Education Council, the Congress on Basic Education, no.3, of 16.698 that instituted the National Curricular Directives for secondary education, as well as the Legal Bases - Part I - of the National Curricular Parameters for secondary education. The analysis of official discourse takes Bardin's (1977, p. 209) proposals as its methodological reference for the models of structural analysis, seeking to make the implicit values and the connotations of the legal texts explicit

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The goals of this study are to identify the potencialities avaiable in elementary public schools for the development of an educational process wich includes environmental issues helpping to find its integration with university in order to contribuite raises teaching levels for a better comprehension of regional environmental problems. Research data were collected through questionnaires and interviews with geography teachers analyising theirs activities and perspectives on the environmental crisis and environmental education. The study also offers sugestions for the devellopment of interdisciplinaires programs trying to contibute for the construction of citizenship showing the importance of better comprehension from environmental problems which includes physical, economics, social, political and cultural aspects.

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This reaserch analysed the developmental stage of fourth grade (primary school) children in ability of writting argumentative texts joint with their context. The reason of this reaserch is the lack of new studies in linguistical area and high ratio of unable students to make this kind of text. It will be showed the analysis of making text by public schools children for three months. These data were analysed trying identify argumentative operators, the kinds of arguments used and the stage of the argumentative ability of these children. The study showed that the introduction of argumentative text in first grades give them more chances of succeed, preparing these pupils in their finishing high school. This fact obviously will make easier the development of their critical point of view, helping the students to think about their living social reality.

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In this work a simple and sensitive procedure to extract organic mercury from water and sediment samples, using methylene chloride in acidic media followed by CVAFS quantification has been developed. The method was evaluated for possible interferents, using different inorganic mercury species and humic acid, no effects being observed. The detection limit for organic mercury was 160 pg and 396 pg for water and sediment samples respectively. The accuracy of the method was evaluated using a certified reference material of methylmercury (BCR-580, estuarine sediment). Recovery tests using methylmercury as surrogate spiked with 1.0 up to 30.0 ng L-1 ranged from 90 up to 109% for water samples, whereas for sediments, recoveries ranged from 57 up to 97%.

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The objective of this study was to evaluate the horizontal and vertical structures of tree community in regeneration in a fragment of a secondary riparian forest at approximately 30 years of age and to identify the most abundant species in each fragment of the forest to determine the sucessional stage. An area of 800 m² was subdivided into 16 samples of 10 x 5 m and all individuals with DBH ≥ 1 cm were sampled and identified for the following analyzes: horizontal parameters (DR, FR, DoR, IVC and IVI), vertical parameters (PSR and RNR) and mixed parameters, from of value of increased importance index (IVIa). The survey measured 689 individuals, belonging to 38 families, 74 genus and 109 species. The total density was 8,614 individuals/ha. The index of Shannon´s diversity was 3.99 and the index of Pielou´s equability was 0.85. Tibouchina pulchra, Psychotria suterella and Endlicheria paniculata obtained high values of IVIa. Guarea macrophylla, Gomidesia anacardiaefolia, Xylopia langsdorffiana and Endlicheria paniculata achieved high values of RNT, indicating adequate natural regeneration in the plot. The initial secondary and umbrophylous species showed the highest ecological importance in this fragment of the forest, with the highest values of sociologic position and importance index. Furthermore, the presence of late secondary species in all layers suggest that the studied fragment is in intermediate succession degree.

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The use of technology to protect and produce vegetables and ornamental plants was developed over several adaptation phases that supported the demand for quality and amount of products. These developments also reduced production costs and climate damage to the crops. Many of these adaptations were carried out by farmers on their own initiative, using different materials and devices to solve their problems. This study was carried out at Agricultural Engineering College - Campinas University/UNICAMP, from December 2002 to January 2003, with the objective of evaluating the deformations of the constructive system of bamboo structure for greenhouses, submitted to different spacing among columns, and different vertical strains. It was tested the use of beams and columns built with bamboo stems from the specie Bambusa tuldoides Munro. The beams and columns were tied together with plastic spacing parts, specially designed to facilitate and standardize the construction of the building, providing more resistance and stability. Three column spaces (2.0, 2.5 and 3.0 m) were evaluated under different load strains. The best result was obtained with a spacing of 2.5 m.

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Quality traits of boneless rib cut (L. dorsi muscle) from Nelore young bulls. To study the meat quality traits of Nelore breed young bulls, and the effect of age (690-780 days) on them, 113 animals were slaughtered after 109 days of intensive feeding with 20% concentrate and 80% roughage. All the carcasses were graded at the slaughter floor by the Federal Inspection and chilled for 24 hours (Tinitial=5°C, Tfinal=2°C). Fifty one half carcasses (right side), type B - B R A S I L `s grading system - from animals of 23 to 26 months were boned and separated into commercial cuts. Two steaks (2.5cm thick) were removed from each boneless rib cut (m. L. dorsi), vacuum packaged and aged for 7 days (0-2°C). The pH varied from 5.44 to 5.83 and only two samples had pH ³ 5.70. The L* (brightness) average value was 34.85. The water and fat content were 75.65% and 1.71%, respectively. The average WB shear force was 6.70kg, and it was not affected by age (690-734 days), but presented a trend (t test, p=0.22) for increasing values between 735 and 780 days. Animal age did not affect other quality traits (t test, p>0.20). It was concluded that the rib cut from Nelore young bulls may not have a good acceptability in exigent markets, and that carcasses graded B, presumed to be the best grade, do not necessarily present the best meat quality characteristics.