10 resultados para Folcculation of mud bank seidments
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Thermal Characteristics of the Mud Nests of the Social Wasp Polybia spinifex (Hymenoptera; Vespidae)
Resumo:
The thermal characteristics of mud nests of Polybia spinifex were investigated by measuring internal and surface temperatures of the nests. The nests had a layer of mud envelope and consisted of mud with fine sand particles. The envelope had a vertically long slit-like entrance hole. The mud nests had high thermal conductivities (0.51-0.67 W/(m degrees C)) comparable to brick, rather than insulation materials of wasps` nests such as paper and wood. It was revealed that the long entrance radiated more heat from the thereto-image. The rate of thermal radiation (emissivity) of the nest surface was 0.80, and the value was similar to that of sand. The internal temperatures of the nests were high from top (T(n1), temperature difference between ambient temperature (T(a)) was 10 degrees C) to bottom (T(n3), difference, 5 degrees C) at noon. On the other hand, the temperature distributions were reversed during the night. Temperature T(n1) was lower by 1 degrees C than T(a), possibly from nightly dew on the top surface, whereas, at the middle point (T(n2),) and T(n3), temperatures were higher by 1 degrees C compared to T(a). Temperature fluctuations (ranges between maximum and minimum temperature) at T(n2) and T(n3) were similar to that of T(a), whereas the values at T(n1) and T(s) were higher than that of T(a).
Resumo:
Due to the effect of catabolite repression, sugar mixtures cannot be metabolized in a rapid and efficient way implicating in lower productivity in bioprocesses using lignocellulosic hydrolysates. In gram-negative bacteria, this mechanism is mediated by the phosphotransferase system (PTS), which concomitantly internalizes and phosphorylates sugars. In this study, we isolated a UV mutant of Burkholderia sacchari, called LFM828, which transports hexoses and pentoses by a non-PTS uptake system. This mutant presented released glucose catabolite repression over the pentoses. In mixtures of glucose, xylose, and arabinose, specific growth rates and the specific sugar consumption rates were, respectively, 10 and 23% higher in LFM828, resulting in a reduced time to exhaust all sugars in the medium. However, in polyhydroxybutyrate (PHB) biosynthesis experiments it was necessary the supplementation of yeast extract to maintain higher values of growth rate and sugar consumption rate. The deficient growth in mineral medium was partially recovered by replacing the ammonium nitrogen source by glutamate. It was demonstrated that the ammonium metabolism is not defective in LFM828, differently from ammonium, glutamate can also be used as carbon and energy allowing an improvement on the carbohydrates utilization for PHB production in LFM828. In contrast, higher rates of ammonia consumption and CO(2) production in LFM828 indicate altered fluxes through the central metabolism in LFM828 and the parental. In conclusion, PTS plays an important role in cell physiology and the elimination of its components has a significant impact on catabolite repression, carbon flux distribution, and PHB biosynthesis in B. sacchari.
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Cancellation tasks have been largely used to evaluate visuospatial function and attention. Cognitive evaluation of low literacy subjects remains a challenge in developing countries, when it becomes necessary to distinguish between what is pathological and what is biased by low education. Performance of river bank dwellers of the Amazon region was studied, in a structured nonverbal cancellation task, verifying their searching strategies (randomized/organized), time of completion, number of correct cancelled targets and number of false-positive targets. A difference was observed in performance and searching strategies between illiterates and literates with only a few years of schooling (mean= 0.8, S.D.=1.6 years of education) across all measures. There was a significant difference between literate groups in the searching strategy, as well as between illiterates who had never attended school and those who had, showing that a minimal contact with graphic presentations and organization of writing was able to modify this cognitive function. (C) 2007 National Academy of Neuropsychology. Published by Elsevier Ltd. All rights reserved.
Resumo:
FAPESP n. 03/04061-2
Resumo:
Focusing on the therapeutic and cosmetic potentials of the thermal water, several processes were developed to achieve a raw material known as fango which presents in its constitution water, clay and organic soil. This research work aimed at characterizing turf, sulphur mud and fango from Araxa, MG, Brazil, through physical, physicochemical, inorganic and organic assessments for cosmetic and topical product proposes. The characterization permitted the determination of relevant parameters to suggest the efficacy (presence, of ions) and safety (absence of toxic metals) of those raw materials for cosmetic and pharmaceutical utilization.
Resumo:
The distribution and density of a population of the narrowback mud crab Panopeus americanus were evaluated, with emphasis on the different developmental stages (juveniles and adults) and sexes. Specimens were collected in a remnant human-impacted mangrove at Araca on the northern coast of Sao Paulo, Brazil, at two-month intervals from January through July 2006, using 1m x 1m sample plots randomly distributed in the intertidal zone. The population was abundant, with a mean density of 14.3 +/- 9.3 individuals/m(2). Larger individuals were more abundant in the upper and middle intertidal zones, whereas smaller crabs were predominant in the lower intertidal and thus remained submerged longer. Males and juveniles were homogeneously distributed. Females preferred regions farther from the waterline. A clustered distribution pattern suggested gregarious behaviour and settling of juveniles in the vicinity of the adults` habitats, in an adaptive process as a function of tidal rhythms.
Resumo:
A number of contemporary studies rightly emphasize the notion that policy outcomes result from institutional determinants. But as a growing literature on institutional development notes, these institutions are themselves impermanent. Sometimes, in crisis moments, institutions are replaced wholesale. More frequently, institutions evolve gradually over time. Using the Brazilian Central Bank as a case study, this article illustrates that the policy-making process itself can be a central driver of gradual institutional development, with institutions evolving through the accumulation of policy choices made over many years and under different policymakers in response to contemporaneous events and unforeseeable economic and political challenges.
Resumo:
Deforestation in southeast Brazil has led to the extinction of Hymenaea courbaril var. stilbocarpa and ex situ conservation has been established. In this study, the levels of genetic diversity and the effective population size of H. courbaril in a germplasm bank were investigated using six nuclear microsatellite loci. A total of 79 and 91 alleles were found in 65 seed-trees and their 176 offspring, respectively. Offspring have a higher average number of alleles per locus (A = 15.2) than seed-trees (A = 13.2), but lower observed heterozygosity (offspring: H (o) = 0.566; seed-trees: H (o) = 0.607). The estimate of outcrossing rate shows that the study population is perfectly outcrossed (t (m) = 0.978, P > 0.05). Significant deviations from random mating were detected through mating among relatives and correlated matings. The average variance in effective population size for each family was 2.63, with a total effective population size retained in the bank of 170.1. These results confirm that the preserved population of H. courbaril retains substantial genetic variability.
Resumo:
The aim of this study was to evaluate the relationship between iron concentration in mature breast milk and characteristics of 136 donors of a Brazilian milk bank. Iron, vitamin A, zinc, and copper concentrations were assessed in human milk and maternal blood. Data were collected on maternal anthropometrics, obstetric, socioeconomic, demographic, and lifestyle factors. Iron, zinc, and copper in milk and zinc and copper in blood were detected by spectrophotometry. Vitamin A in milk and blood was determined by high-performance liquid chromatography. Hemoglobin was measured by electronic counting and serum iron and ferritin by colorimetry and chemoluminescence, respectively. Transferrin and ceruloplasmin were determined by nephelometry. According to multivariate linear regression analysis, iron in milk was positively associated with vitamin A in milk and with smoking but negatively associated with timing of breast milk donation (P < .001). These results indicate that iron concentration in milk of Brazilian donors may be influenced by nutritional factors and smoking. J Hum Lact. 26(2):175-179