10 resultados para Fertilizante granular
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
Due to the major role of Streptococcus mutans and Streptococcus sobrinus in the etiology of dental caries, it is important to use culture media that allow for differentiating these bacterial species. The aim of this study was to evaluate the suitability of a modified SB-20 culture medium (SB-20M) for the isolation and morphological differentiation of S. mutans and S. sobrinus, compared to biochemical identification (biotyping). Saliva samples were collected using the spatula method from 145 children, seeded on plates containing the SB-20M, in which sucrose was replaced by coarse granular cane sugar, and incubated in microaerophilia at 37 degrees C during 72 h. Identification of the microorganisms was performed under stereomicroscopy based on colony morphology of 4904 colonies. The morphological identification was examined by biochemical tests of 94 randomly selected colonies with the macroscopic characteristic of S. mutans and S. sobrinus using sugar fermentation, resistance to bacitracin and production of hydrogen peroxide. There was no statistically significant difference (p> 0.05) between morphological identification in the SB-20M medium and biochemical identification (biotyping). Biotyping confirmed that S. mutans and S. sobrinus colonies were correctly characterized in the SB-20M in 95.8% and 95.5% of the cases, respectively. Of the mutans streptococci detected in the children 98% were S. mutans and 2% S. sobrinus. The SB-20M medium is reliable for detection and direct morphological identification of S. mutans and S. sobrinus. (C) 2010 Elsevier GmbH. All rights reserved.
Resumo:
Amaranth has attracted a great deal of interest in recent decades due to its valuable nutritional, functional, and agricultural characteristics. Amaranth seeds can be cooked, popped, roasted, flaked, or extruded for consumption. This study compared the in vitro starch digestibility of processed amaranth seeds to that of white bread. Raw seeds yielded rapidly digestible starch content (RDS) of 30.7% db and predicted glycemic index (pGI) of 87.2, the lowest among the studied products. Cooked, extruded, and popped amaranth seeds had starch digestibility similar to that of white bread (92.4, 91.2, and 101.3, respectively), while flaked and roasted seeds generated a slightly increased glycemic response (106.0 and 105.8, respectively). Cooking and extrusion did not alter the RDS contents of the seeds. No significant differences were observed among popped, flaked, and roasted RDS contents (38.0%,46.3%, and 42.9%, respectively), which were all lower than RDS content of bread (51.1%). Amaranth seed is a high glycemic food most likely because of its small starch granule size, low resistant starch content (< 1%), and tendency to completely lose its crystalline and granular starch structure during those heat treatments.
Resumo:
In the developing cerebellum, proliferation of granular neuroprogenitor (GNP) cells lasts until the early postnatal stages when terminal maturation of the cerebellar cortex occurs. GNPs are considered cell targets for neoplastic transformation, and disturbances in cerebellar GNP cell proliferation may contribute to the development of pediatric medulloblastoma. At the molecular level, proliferation of GNPs is regulated through an orchestrated action of the SHH, NOTCH, and WNT pathways, but the underlying mechanisms still need to be dissected. Here, we report that expression of the E2F1 transcription factor in rat GNPs is inversely correlated with cell proliferation rate during postnatal development, as opposed to its traditional SHH-dependent induction of cell cycle. Proliferation of GNPs peaked at postnatal day 3 (P3), with a subsequent continuing decrease in proliferation rates occurring until P12. Such gradual decline in proliferating neuroprogenitors paralleled the extent of cerebellum maturation confirmed by histological analysis with cresyl violet staining and temporal expression profiling of SHH, NOTCH2, and WNT4 genes. A time course analysis of E2F1 expression in GNPs revealed significantly increased levels at P12, correlating with decreased cell proliferation. Expression of the cell cycle inhibitor p18 (Ink4c) , a target of E2F1, was also significantly higher at P12. Conversely, increased E2F1 expression did not correlate with either SMAC/DIABLO and BCL2 expression profiles or apoptosis of cerebellar cells. Altogether, these results suggest that E2F1 may also be involved in the inhibition of GNP proliferation during rat postnatal development despite its conventional mitogenic effects.
Resumo:
Ureaplasma diversum infection in bulls may result in seminal vesiculitis, balanoposthitis and alterations in spermatozoids. In cows, it can cause placentitis, fetal alveolitis, abortion and the birth of weak calves. U. diversum ATCC 49782 (serogroups A), ATCC 49783 (serogroup C) and 34 field isolates were used for this study. These microorganisms were submitted to Polymerase Chain Reaction for 16S gene sequence determination using Tact High Fidelity and the products were purified and bi-directionally sequenced. Using the sequence obtained, a fragment containing four hypervariable regions was selected and nucleotide polymorphisms were identified based on their position within the 16S rRNA gene. Forty-four single nucleotide polymorphisms (SNP) were detected. The genotypic variability of the 16S rRNA gene of U. diversum isolates shows that the taxonomy classification of these organisms is likely much more complex than previously described and that 16S rRNA gene sequencing may be used to suggest an epidemiologic pattern of different origin strains. (c) 2011 Elsevier B.V. All rights reserved.
Resumo:
We performed measurements of electrical resistivity as a function of temperature, rho(T), in polycrystalline samples of YBa(2)Cu(3)O(7-delta) (Y-123) subjected to different uniaxial compacting pressures. We observed by using X-ray diffractometry that samples have a very similar composition. Most of the identified peaks are related to the superconducting Y-123 phase. Also, from the X-ray diffraction patterns performed, in powder and pellet samples, we estimated the Lotgering factor along the (00l) direction, F((00l)). The results indicate that F((00l)) increases from 0.13 to 0.16. From electrical resistivity measurements as a function of temperature, we were able to separate contributions arising from both the grain misalignment and microstructural defects. We found appreciable degradation in the normal-state transport properties of samples with an increase in uniaxial compacting pressure. It seems that this type of behavior is associated with an increase in the influence of microstructural defects at the intergranular level. The experimental results are analyzed in the framework of a current conduction model of granular samples.
Resumo:
Bose systems, subject to the action of external random potentials, are considered. For describing the system properties, under the action of spatially random potentials of arbitrary strength, the stochastic mean-field approximation is employed. When the strength of disorder increases, the extended Bose-Einstein condensate fragments into spatially disconnected regions, forming a granular condensate. Increasing the strength of disorder even more transforms the granular condensate into the normal glass. The influence of time-dependent external potentials is also discussed. Fastly varying temporal potentials, to some extent, imitate the action of spatially random potentials. In particular, strong time-alternating potential can induce the appearance of a nonequilibrium granular condensate.
Resumo:
We have studied a Bose-Einstein condensate of (87)Rb atoms under an oscillatory excitation. For a fixed frequency of excitation, we have explored how the values of amplitude and time of excitation must be combined in order to produce quantum turbulence in the condensate. Depending on the combination of these parameters different behaviors are observed in the sample. For the lowest values of time and amplitude of excitation, we observe a bending of the main axis of the cloud. Increasing the amplitude of excitation we observe an increasing number of vortices. The vortex state can evolve into the turbulent regime if the parameters of excitation are driven up to a certain set of combinations. If the value of the parameters of these combinations is exceeded, all vorticity disappears and the condensate enters into a different regime which we have identified as the granular phase. Our results are summarized in a diagram of amplitude versus time of excitation in which the different structures can be identified. We also present numerical simulations of the Gross-Pitaevskii equation which support our observations. (C) 2011 by Astro Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA
Resumo:
Several major iron deposits occur in the Quadrilatero Ferrifero (QF), southeastern region of Brazil, where metamorphosed and heterogeneously deformed banded iron formation (BIF) of the Caue Formation, regionally called itabirite, was transformed into high- (Fe >64%) and lowgrade (30%
Resumo:
Anomalous concentrations of fluoride in groundwater were identified in 19 drilling wells in the Salto-Indaiatuba region, Sao Paulo State, with an average concentration of 3.03 mg dm(-3) and a maximum of 6.95 mg dm(-3), which constitute a restriction for the water`s usage in terms of human consumption. The wells exploit water from the Tubarao Aquifer (sedimentary, granular) and Crystalline Aquifer (granitic, fractured), used for sanitary or industrial purposes. These groundwaters are typically HCO(3) and HCO(3)-SO(4) types, with high concentrations of HCO(3) -and Na(+) and high pH-values between 7.5 and 10.0. The highest concentrations of F-are associated to the Tubarao and Tubarao/Crystalline aquifer drilling wells. The presence of F-in groundwater is controlled by these high pH-values, alkalinity, and fluorine availability. The source of fluoride in the Tubarao and Crystalline Aquifers can be related to the percolation of hydrothermal fluids associated with Mesozoic lava flow, emplaced due to the opening of Atlantic Ocean and/or hydrolysis of fluorine-rich minerals and clay minerals.
Resumo:
This work deals with the structural and vibrational characterization of PANI nanofibers prepared through interfacial polymerization using different concentrations of HCl aqueous solution. The results were compared to those obtained by PANI prepared through the conventional route. X-ray diffraction and small-angle X-ray scattering techniques showed that high concentrations of HCl solutions used in the preparation of the PANI nanofibers reduce their crystallinity. The increase of regions with granular morphology was also observed in the scanning electron microscopy images. The changes in the resonance Raman spectra from 200 to 500 cm(-1), FTIR spectra, and the EPR data of the PANI nanofibers reveal an increase in the torsion angles of C-ring-N-C-ring segments owing the formation of bipolarons in the PANI backbone higher than the PANI samples prepared by conventional route.