432 resultados para Northeastern Backlands of Brazil


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This work describes the relative condition factor of the Hypostomus strigaticeps, Astyanax altiparanae, Astyanax scabripinnis, Astyanax fasciatus, Astyanax sp1., Characidium aff. zebra, Piabina argentea, Hypostomus ancistroides, Hypostomus sp1., Parodon tortuosus, Serrapinus heterodon, and Bryconamericus sp., of the APA of São Pedro and Analândia (22°-23°S and 47°30'-48°30'W). The condition factor provides information about the physical state of the animal in the environment. In order to compare different species, the relative condition factor was used. Variations in this factor were correlated with variations through the year and with subsequent alterations in the physiological state of the fishes. The relative condition factor was shown to be efficient in indicating changes in fish condition throughout the year.

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Amphibians, and especially the anurans (frogs and toads), exhibit a greater diversity of reproductive modes than other tetrapod vertebrates. Twenty-nine reproductive modes have been recognized for the anurans; we propose 10 more, elevating by more than 34% the number of reproductive modes known for anurans worldwide. These newly recognized reproductive modes for the frogs elevate by almost 48% the number of anuran reproductive modes known for the Neotropics. The highly complex topography of the Atlantic forest, breaking up the biome into many small microhabitats, and the high humidity, which reduces desiccation risks, have enabled the evolution of reproductive specializations such as eggs or tadpoles that develop out of water. Nearly 90% of the Atlantic forest has been cleared, and because several anurans are endemic to this region or have specialized reproductive modes dependent on the forest, this partly explains the generalized population declines and large numbers of species that have disappeared in the last few decades. © 2005 American Institute of Biological Sciences.

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A study on the presence of herbicides, namely simazine, metribuzin, metolachlor, trifluralin, atrazine and two metabolites, deisopropylatrazine (DIA) and deethylatrazine (DEA), was performed in ground and surface waters from Primavera do Leste region, Mato Grosso state (Middle West of Brazil). The analytical procedure was based on solid-phase extraction (SPE) with Sep-Pak C18 disposable cartridges and ethyl acetate for elution solvent. Residue levels were determined by gas chromatography with nitrogen-phosphorus detection. For most of the pesticides average recoveries at different fortification levels were >with relative standard deviation < The recoveries of DIA and trifluralin in water were 25% and 56%, respectively, which were attributed to the incomplete retention of DIA and strong retention on the sorbing material and high volatility of trifluralin. Detection limits ranged from 0.023 to 0.088 μg L-1. This method was applied for the analysis of 5 superficial water samples and 28 groundwater samples, in places used for human consumption without previous treatment, collected in Primavera do Leste, Mato Grosso, Brazil. Results indicated that the highest level of contamination in a water sample was 1.732 μg L-1 for metolachlor, while metribuzin was the most frequently detected herbicide with maximum concentration of 0.351 μg L-1. ©2006 Sociedade Brasileira de Química.

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Noise is the most frequent type of occupational exposure and can lead to both auditory and extra-auditory dysfunction as well as increasing the risk of work accidents. The purpose of this study was to estimate the attributable fraction of work accidents related to occupational noise exposure in a medium-sized city in Southeast Brazil. In this hospital-based case-control study, including 600 cases and 822 controls, the odds ratio of work accidents (controlled for several covariables) was obtained classifying occupational noise exposure into four levels and determining the prevalence at each level. Based on these data, the calculated attributable fraction was 0.3041 (95%CI: 0.2341-0.3676), i.e., 30% of work accidents in the study area were statistically associated with occupational noise exposure. The authors discuss the causes of this association and the implications for the prevention of work accidents.

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To highlight the transmission and major phylogenetic clades of Mycobacterium tuberculosis, a retrospective study was carried out at two health facilities in a small agro-industrial area in São Paulo, Brazil, that has a low tuberculosis incidence rate. IS6110-RFLP and spoligotyping were performed on the isolates, with the former revealing that 31.3% (35/112) of strains were clustered. Epidemiological links were found in 16 of the 35 clustered patients and were associated with transmission among patients living in public housing. Spoligotyping grouped 62.8% of the strains. The T genetic family predominated among the isolates. Of interest is that five strains had a pattern characteristic of African or Asian origin (ST535), and two others were of the rare localized type ST1888 (BRA, VEN). In addition, three new types-1889, 1890, and 1891-were identified. Spoligotyping showed that some ST may be circulating to or from Brazil, and RFLP revealed ongoing transmission in inadequately ventilated public-housing buildings. This may point to a failure in tuberculosis control policy.

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The aim of this study was to evaluate the urinary fluoride excretion of 2- to 7-year-old children exposed to different water fluoride concentrations in the city of Catolé do Rocha, PB, Brazil. Forty-two children were allocated to 3 groups according to the concentration of fluoride in the water: G1 (n=10; 0.5-1.0 ppm F), G2 (n=17; 1.1-1.5 ppm F) and G3 (n= 15; >1.51 ppm F). The study was carried out in two 1-week phases with 1-month interval between the moments of data collection: in the first phase, the children used a fluoride toothpaste (FT) (1,510 ppm F) for 1 week, whereas in the second phase a non-fluoride toothpaste (NFT) was used. The urine was collected in a 24-h period in each week-phase according to Marthaler's protocol. The urinary fluoride excretion data expressed as mean (SD) in ì g/24 h were: G1-FT= 452.9 (290.2); G1-NFT= 435.1 (187.0); G2-FT= 451.4 (224.0); G2-NFT= 430.3 (352.5); G3-FT=592.3 (390.5); and G3-NFT=623.6 (408.7). There was no statistically significant difference between the water fluoride groups, and regardless of the week phase (ANOVA, p>0.05). The use of fluoride toothpaste (1,510 ppmF) did not promote an increase in urinary fluoride excretion. There was a trend, though not significant, as to the increase of urine fluoride concentration in relation to fluoride concentrations in the water. The excretion values suggest that some children are under risk to develop dental fluorosis and information about the appropriate use of fluoride is necessary in this area.

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This study aims to inventory and assess the aquatic macroinvertebrates fauna in two artificial reservoirs into conservation units with differences regarding conservation level and to anthropogenic impacts. The samplings were carried out in Caetetus Ecological Station and Bauru City Zoological Park, where some physical and chemical variables also were measured. The results obtained indicated that the Caetetus Ecological Station is more effective in the conservation of the diversity of aquatic macroinvertebrates compared to Bauru City Zoological Park. These results can be attributed to the strong anthropogenic impact suffered by the reservoir in Bauru and demonstrate the importance of these areas in maintaining the diversity of aquatic macroinvertebrates community.

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Guava and araçá, species of the Psidium genus, are important options for Brazilian agribusiness, especially the former species, due to their fruit characteristics, such as appearance, taste and richness in minerals and phenolic compounds. These fruits can be consumed in natura or in several processed forms. The active germplasm bank is an important tool for genetic resource characterization and plant breeding studies. Sixty guava and ten araçá accessions of the Psidium active germplasm, sampled in 44 different Brazilian regions and grown at Embrapa Semiarid, were chemically and biochemically characterized in order to support breeding programs. The accessions were grown in a randomized block design, with two replications and three plants/plot. The sugar, proteins, soluble solids, titratable acidity, calcium, magnesium, iron and phosphorus contents were determined. Large variations were observed in the analyzed compounds, which could be attributed to the diversity of genotypes and also to the environmental conditions, which affect the plant metabolism. The high variability observed in most parameters of the accessions is an important factor for the improvement of these species. Most guava accessions showed higher titratable acidity and soluble solids than those found in commercial cultivars and, in araçá, these levels were even higher, which makes them promising for commercial exploitation. Moreover, fruits of the guava and araçá accessions present good sources of sugars and minerals. Special attention should be given to some guava and araçá accessions from Maranhão and Pernambuco States, respectively, which showed high levels for titratable acidity, soluble solids, SS/TA ratio, total soluble sugars, calcium, magnesium and iron, should be targets of breeding programs for new Psidium cultivars. © ISHS.

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Nowadays, L1 SBAS signals can be used in a combined GPS+SBAS data processing. However, such situation restricts the studies over short baselines. Besides of increasing the satellite availability, SBAS satellites orbit configuration is different from that of GPS. In order to analyze how these characteristics can impact GPS positioning in the southeast area of Brazil, experiments involving GPS-only and combined GPS+SBAS data were performed. Solutions using single point and relative positioning were computed to show the impact over satellite geometry, positioning accuracy and short baseline ambiguity resolution. Results showed that the inclusion of SBAS satellites can improve the accuracy of positioning. Nevertheless, the bad quality of the data broadcasted by these satellites limits their usage. © Springer-Verlag Berlin Heidelberg 2012.

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In the Nilo Coelho irrigation scheme, Brazil, the natural vegetation has been replaced by irrigated agriculture, bringing importance for the quantification of the effects on the energy exchanges between the mixed vegetated surfaces and the lower atmosphere. Landsat satellite images and agro-meteorological stations from 1992 to 2011 were used together, for modelling these exchanges. Surface albedo (α0), NDVI and surface temperature (T0) were the basic remote sensing retrieving parameters necessary to calculate the latent heat flux (λE) and the surface resistance to evapotranspiration (rs) on a large scale. The daily net radiation (Rn) was obtained from α0, air temperature (Ta) and short-wave transmissivity (τsw) throughout the slob equation, allowing the quantification of the daily sensible heat flux (H) by residual in the energy balance equation. With a threshold value for rs, it was possible to separate the energy fluxes from crops and natural vegetation. The averaged fractions of Rn partitioned as H and λE, were in average 39 and 67%, respectively. It was observed an increase of the energy used for the evapotranspiration process inside irrigated areas from 51% in 1992 to 80% in 2011, with the ratio λE/Rn presenting an increase of 3 % per year. The tools and models applied in the current research, can subsidize the monitoring of the coupled climate and land use changes effects in irrigation perimeters, being valuable when aiming the sustainability of the irrigated agriculture in the future, avoiding conflicts among different water users. © 2012 SPIE.

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We evaluated the population dynamics of Acetes americanus Ortmann, 1893 focusing on sex ratio, individual growth, longevity, and the juvenile recruitment period. Samples were collected monthly from January 2006 to June 2007 in the bay of Ubatuba, Brazil. Specimen growth was identified for each gender, and the chosen cohorts were fitted in a von Bertalanffy Growth Model (VBGM); longevity was estimated by the von Bertalanffy inverse equation, considering 99% of the asymptotic length. A total of 6881 individuals (2343 males and 4538 females) were captured. On average the body size (total length) was greater in females (14.64 ± 3.34 mm) than in males (12.27 ± 1.86 mm). The mean growth curves (obtained by grouping the cohorts for each sex), provided estimates of TL∞ = 19.33 mm, k = 0.02 and t0 = -0.12 days for females and TL∞ = 15.13 mm, k = 0.03 and to = -0.07 days for males, where TL∞ is the asymptotic length, k is coefficient of growth and to is the theorical age when the size is equal to 0. Longevity was estimated at 0.61 years for females and 0.50 years for males. The sex ratio tended to favor females, which corroborates with others studies of sergestids. Our finding that males of A. americanus have higher values of k and therefore achieve a smaller size relative to females has been observed in other penaeids. We concluded that this differential growth pattern between the sexes is found across Dendrobranchiata. The life cycles of penaeids have an average duration of approximately 1-2 years, but our results corroborate other studies that estimate a shorter longevity for Acetes, as species of this genus are typically smaller in size. We found continuous recruitment with two main peaks observed during the study period, corroborating previous studies of Acetes. © The Crustacean Society, 2013. Published by Brill NV, Leiden.

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The objective of this study was to define production environments by grouping different environmental factors and, consequently, to assess genotype by production environment interactions on weaning weight (WW) in the Angus populations of Brazil and Uruguay. Climatic conditions were represented by monthly temperature means (°C), minimum and maximum temperatures in winter and summer respectively and accumulated rainfall (mm/year). Mode in month of birth and weaning, and calf weight (kg) and age (days) at weaning were used as indicators of management conditions of 33 and 161 herds in 13 and 34 regions in Uruguay and Brazil, respectively. Two approaches were developed: (a) a bi-character analysis of extreme sub-datasets within each environmental factor (bottom and top 33% of regions), (b) three different production environments (including farms from both countries) were defined in a cluster analysis using standardized environmental factors. To identify the variables that influenced the cluster formation, a discriminant analysis was previously carried out. Management (month, age and weight at weaning) and climatic factors (accumulated rainfalls and winter and summer temperatures) were the most important factors in the clustering of farms. Bi or trivariate analyses were performed to estimate heritability and genetic correlations for WW in extreme sub-datasets within environmental factor or between clusters, using MTDFREML software. Heritability estimates of WW in the first approach ranged from 0.27 to 0.54, and genetic correlations between top and bottom sub-datasets within environmental factors, from -0.29 to 0.70. In the cluster approach, heritabilities were 0.58±0.04 for cluster 1, 0.31±0.01 for Cluster 2 and 0.40±0.02 for Cluster 3. Genetic correlations were 0.27±0.08, 0.32±0.09 and 0.33±0.09, between clusters 1 and 2, 1 and 3, and 2 and 3, respectively. Both approaches suggest the existence of genotype x environment interaction for weaning weight in Angus breed of Brazil and Uruguay. © 2012 Elsevier B.V.

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Ninety-five specimens from 13 species of lizard collected during a herpetofaunal monitoring programme of the Faxinal II power plant, municipality of Aripuanã, state of Mato Grosso, Brazil (southern Amazon region) were examined for helminths. A total of 21 helminth species (16 Nematoda, 1 Cestoda and 4 Trematoda) were recovered, with an overall prevalence of 67.37%. Seventeen new host records and seven new locality records are reported. A low number of specialists and core helminth species were found. Lizard body size was positively correlated with both the total number of helminth species and individuals. Active foragers exhibited higher helminth diversity. However, sit-and-wait foragers, especially Plica plica, had similar diversity values as active foragers and harboured more helminth species. The degree of similarity in helminth fauna was higher among closely related host species. Copyright © 2011 Cambridge University Press.

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We describe herein the design and development of an innovative tool called the NuBBE database (NuBBEDB), a new Web-based database, which incorporates several classes of secondary metabolites and derivatives from the biodiversity of Brazil. This natural product database incorporates botanical, chemical, pharmacological, and toxicological compound information. The NuBBEDB provides specialized information to the worldwide scientific community and can serve as a useful tool for studies on the multidisciplinary interfaces related to chemistry and biology, including virtual screening, dereplication, metabolomics, and medicinal chemistry. The NuBBEDB site is at http://nubbe.iq.unesp.br/nubbeDB.html. © 2013 The American Chemical Society and American Society of Pharmacognosy.

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This investigation aimed to study the relative growth, morphological sexual maturity and fecundity of the swimming crab Achelous spinicarpus in a tropical region, on the south-eastern continental shelf of Brazil (25°S). Biometry of all specimens was conducted, including measurements of the cephalothorax, cheliped, abdomen and gonopods. Relative growth was described based on the equation for allometry (y = axb), and size at sexual maturity was determined from inflections in relations involving the cheliped, gonopods (males), and abdomen (females), as dependent variables, related to the cephalothorax width (independent variable). Fecundity was estimated by the gravimetric method. The relations of the length of the chelar propodus and carpal spine to the carapace width without the lateral spines (CW) showed positive allometry in both sexes, with a significant variation in the constant 'b' for males between the developmental stages (juvenile and adult) and the size at maturity estimated at 37 mm CW. In females, the abdomen was most appropriate for the estimate of morphological maturity, which occurred at a smaller size (32 mm CW), with a change in the growth pattern between the stages, passing from isometric (juveniles) to positive allometric (adults). The gonopods also showed different growth rates between developmental stages, in synchrony with the variables of the cheliped. Mean fecundity for the species was 53,984 eggs, with a positive correlation between the number of eggs exteriorized and the size of the female; the equations allowed interconversion between these variables, due to the adjustment of the power function (r2 ≥ 86%). © 2012 Marine Biological Association of the United Kingdom.