14 resultados para Education, Adult and Continuing|Language, Rhetoric and Composition|Education, Higher

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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To assess the impact and fate of the summer phytoplankton bloom on Antarctic benthos, we evaluated temporal and spatial patterns in macrofaunal abundance and taxonomic composition along a transect crossing the West Antarctic Peninsula (WAP) continental shelf As part of the FOODBANCS project, we sampled three sites at 550-625 m depths during five cruises occurring in November 1999, February-March 2000, June 2000, October 2000 and March 2001. We used a combination of megacore and box-core samplers to take 81 samples, and collected over 30,000 macrofaunal individuals, one of the largest sampling efforts on the Antarctic shelf to date. Comparison of the two sampling methodologies (box core and megacore) indicates similar macrofaunal densities, but with significant differences in taxonomic composition, a reflection of the different spatial scales of sampling. Macrorfaunal abundances on the WAP shelf were relatively high compared to other Antarctic shelf settings. At two of the three sampling sites, macrofaunal abundance remained constant throughout the year, which is consistent with the presence of a sediment `food bank`. Differences were observed in taxonomic composition at the site closest to the coast (Station A), driven by higher abundances of subsurface-deposit feeders. A significant temporal response was observed in the ampharetid polychaetes at Station A, with an abundance peak in the late fall post-bloom period; this may have resulted from juvenile recruitment during the summer bloom. Familial composition of macrofaunal polychaetes on the WAP shelf is more closely related to deep-sea abyssal fauna than to other shelf regions, and we hypothesize that this is a result of both local ecological conditions (low temperatures) and a reflection of historical processes such as extinctions on the Antarctic shelf during previous glacial maxima followed by recolonization from the deep sea. (C) 2008 Elsevier Ltd. All rights reserved.

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The West Antarctic Peninsula (WAP) shelf experiences intense seasonal and interannual variability in phytoplankton production and particulate-organic-carbon flux to the seafloor. To explore the response of the megabenthic community to this production variability, we conducted video surveys of epibenthic megafauna at three stations on the WAP shelf in Nov-Dec 1999, Mar 2000, Jun 2000, Oct-Nov 2000, and Feb-Mar 2001. The epibenthic megafauna was dominated (>90%) by elasipod holothurians, irregular urchins and anthozoans, with total abundances ranging from 19 to 152 ind. 1 00 m(-2). The abundance of three of the dominant taxa (Protelpidia murrayi, Peniagone vignomi, and Amphipneustes spp.) varied significantly across seasons (p <0.05), although variations were not tightly correlated with the summer bloom cycle. The irregular urchins in the genus Amphipneustes varied 5-fold in abundance at single stations, with maximum densities (an average of 10.1 ind. 100 m(-2)) attained in Jun 2000. Abundances of the elasipod holothurians P. murrayi (1-121 ind. 100 m(-2)) and P. vignoni (0.7-27.5 ind. 100 m(-2)) fell within the range for elasipod holothurians from other bathyal regions measured using image analysis. The abundance of P. murrayi increased up to 6-fold from a single Jun-Oct recruitment pulse, while changes in the abundance of P. vignoni (over 2-fold higher in Feb-Mar 2001) apparently resulted from immigration during the presence of a 1-2 cm thick carpet of fresh phytocletritus. Based on the ratio of the number of fecal casts per individual, elasipod holothurians increased surface-deposit feeding rates by >= 2-fold while phytocletritus was present at the seafloor. Nonetheless, these surface-deposit feeders appeared to feed and egest sediments throughout the winter, which is consistent with year-round persistence of a labile food bank in surficial sediments on the deep WAP shelf.

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OBJECTIVE: To analyze major histocompatibility complex expression in the muscle fibers of juvenile and adult dermatomyositis. METHOD: In total, 28 untreated adult dermatomyositis patients, 28 juvenile dermatomyositis patients (Bohan and Peter's criteria) and a control group consisting of four dystrophic and five Pompe's disease patients were analyzed. Routine histological and immunohistochemical (major histocompatibility complex I and II, StreptoABComplex/HRP, Dakopatts) analyses were performed on serial frozen muscle sections. Inflammatory cells, fiber damage, perifascicular atrophy and increased connective tissue were analyzed relative to the expression of major histocompatibility complexes I and II, which were assessed as negatively or positively stained fibers in 10 fields (200X). RESULTS: The mean ages at disease onset were 42.0 +/- 15.9 and 7.3 +/- 3.4 years in adult and juvenile dermatomyositis, respectively, and the symptom durations before muscle biopsy were similar in both groups. No significant differences were observed regarding gender, ethnicity and frequency of organ involvement, except for higher creatine kinase and lactate dehydrogenase levels in adult dermatomyositis (p<0.050). Moreover, a significantly higher frequency of major histocompatibility complex I (96.4% vs. 50.0%, p<0.001) compared with major histocompatibility complex II expression (14.3% vs. 53.6%, p = 0.004) was observed in juvenile dermatomyositis. Fiber damage (p = 0.006) and increased connective tissue (p<0.001) were significantly higher in adult dermatomyositis compared with the presence of perifascicular atrophy (p<0.001). The results of the histochemical and histological data did not correlate with the demographic data or with the clinical and laboratory features. CONCLUSION: The overexpression of major histocompatibility complex I was an important finding for the diagnosis of both groups, particularly for juvenile dermatomyositis, whereas there was lower levels of expression of major histocompatibility complex II than major histocompatibility complex I. This finding was particularly apparent in juvenile dermatomyositis.

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This study evaluated the effects of the organic loading rate (OLR) and pH buffer addition on hydrogen production in two anaerobic fluidized bed reactors (AFBRs) operated simultaneously. The AFBRs were fed with glucose, and expanded clay was used as support material. The reactors were operated at a temperature of 30 degrees C, without the addition of a buffer (AFBR1) and with the addition of a pH buffer (AFBR2, sodium bicarbonate) for OLRs ranging from 19.0 to 140.6 kg COD m(-3) d(-1) (COD: chemical oxygen demand). The maximum hydrogen yields for AFBR1 and AFBR2 were 2.45 and 1.90 mol H-2 mol(-1) glucose (OLR of 84.3 kg COD m(-3) d(-1)), respectively. The highest hydrogen production rates were 0.95 and 0.76 L h(-1) L-1 for AFBR1 and AFBR2 (OLR of 140.6 kg COD m(-3) d(-1)), respectively. The operating conditions in AFBR1 favored the presence of such bacteria as Clostridium, while the bacteria in AFBR2 included Clostridium, Enterobacter, Klebsiella, Veillonellaceae, Chryseobacterium, Sporolactobacillus, and Burkholderiaceae. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

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This work is part of a study that focused on analyzing the contributions of didactic activities related to scientific language rhetoric characteristics aimed at developing students' abilities to identify such characteristics in chemistry scientific texts and critical reading of those texts. In this study, we present the theoretical basis adopted to determine the scientific discourse characteristics and for the production of the didactic material used in those activities. Latour, Coracini and Campanario studies on persuasive rhetorical strategies present in scientific articles aided the production of such material.

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Rice bran oil was obtained from rice bran by solvent extraction using ethanol. The influence of process variables, solvent hydration (0-24% of water, on mass basis), temperature (60-90 degrees C), solvent-to-rice bran mass ratio (2.5:1 to 4.5:1) and stirrer speed (100-250 rpm) were analysed using the response surface methodology. The extraction yield was highly affected by the solvent water content, and it varied from 8.56 to 20.05 g of oil/100 g of fresh rice bran (or 42.7-99.9% of the total oil available) depending on the experimental conditions. It was observed that oryzanol and tocols behave in different ways during the extraction process. A larger amount of tocols is extracted from the solid matrix in relation to gamma-oryzanol. It was possible to obtain values from 123 to 271 mg of tocols/kg of fresh rice bran and 1527 to 4164 mg of oryzanol/kg of fresh rice bran, indicating that it is feasible to obtain enriched oil when this renewable solvent is used. No differences in the chemical composition of the extracted oils were observed when compared to the data cited in the literature. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

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Clinical and experimental evidence suggest that estrogens have a major impact on cognition, presenting neurotrophic and neuroprotective actions in regions involved in such function. In opposite, some studies indicate that certain hormone therapy regimens may provoke detrimental effects over female cognitive and neurological function. Therefore, we decided to investigate how estrogen treatment would influence cognition and depression in different ages. For that matter, this study assessed the effects of chronic 17 beta-estradiol treatment over cognition and depressive-like behaviors of young (3 months old), adult (7 months old) and middle-aged (12 months old) reproductive female Wistar rats. These functions were also correlated with alterations in the serotonergic system, as well as hippocampal BDNF. 17 beta-Estradiol treatment did not influence animals' locomotor activity and exploratory behavior, but it was able to improve the performance of adult and middle-aged rats in the Morris water maze, the latter being more responsive to the treatment. Young and adult rats displayed decreased immobility time in the forced swimming test, suggesting an effect of 17 beta-estradiol also over such depressive-like behavior. This same test revealed increased swimming behavior, triggered by serotonergic pathway, in adult rats. Neurochemical evaluations indicated that 17 beta-estradiol treatment was able to increase serotonin turnover rate in the hippocampus of adult rats. Interestingly, estrogen treatment increased BDNF levels from animals of all ages. These findings support the notion that the beneficial effects of 17 beta-estradiol over spatial reference memory and depressive-like behavior are evident only when hormone therapy occurs at early ages and early stages of hormonal decline. (C) 2011 Elsevier B.V. All rights reserved.

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The present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (Zn), copper (Cu) and selenium (Se) on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. Nineteen Holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9) or inorganic (n = 10) sources of Zn, Cu and Se from 60 days before the expected date of calving to 80 days of lactation. Samples of feed, orts and milk were collected for analysis. Body condition score (BCS) was determined and blood samples were collected for analysis of Zn, Cu and Se concentrations, as well as for metabolic profile. Supplying organic or inorganic sources of Zn, Cu, and Se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and BCS or change the BCS in cows from 60 days before the expected date of calving to 80 days of lactation. An effect of time was observed on all feed intake variables, plasma concentrations of Zn and Se, milk yield, milk protein content, BCS and change in BCS.

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The aim of this study was to analyze the rat temporomandibular joint (TMJ) synovial membrane at different ages using light, scanning, and transmission electron microscopy. Under light microscopic analysis, the TMJ structures were observed such as condyle, capsule, disk, the synovial membrane collagen type, and cells distribution. In the scanning electron microscopy, the synovial membrane surface exhibited a smooth aspect in young animals and there was an increase with ageing in the number of folds. The transmission electron microscopic analysis showed more synoviocytes in the synovial layer in the young group and still a great number of vesicles and cisterns dilation of rough endoplasmic reticulum in the aged group. In the three groups, a dense layer of collagen fibers in the synovial layer and cytoplasmic extensions were clearly seen. It was possible to conclude that synovial membrane structures in aged group showed alterations contributing to the decrease in joint lubrication and in the sliding between disk and joint surfaces. These characteristic will reflect in biomechanics of chewing, and may cause the TMJ disorders, currently observed in clinical processes. Microsc. Res. Tech. (c) 2012 Wiley Periodicals, Inc.

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Background: A recent microarray study identified a set of genes whose combined expression patterns were predictive of poor outcome in a cohort of adult adrenocortical tumors (ACTs). The difference between the expression values measured by qRT-PCR of DLGAP5 and PINK1 genes was the best molecular predictor of recurrence and malignancy. Among the adrenocortical carcinomas, the combined expression of BUB1B and PINK1 genes was the most reliable predictor of overall survival. The prognostic and molecular heterogeneity of ACTs raises the need to study the applicability of these molecular markers in other cohorts. Objective: To validate the combined expression of BUB1B, DLGAP5, and PINK1 as outcome predictor in ACTs from a Brazilian cohort of adult and pediatric patients. Patients and methods: BUB1B, DLGAP5, and PINK1 expression was assessed by quantitative PCR in 53 ACTs from 52 patients - 24 pediatric and 28 adults (one pediatric patient presented a bilateral asynchronous ACT). Results: DLGAP5 PINK1 and BUB1B PINK1 were strong predictors of disease-free survival and overall survival, respectively, among adult patients with ACT. In the pediatric cohort, these molecular predictors were only marginally associated with disease-free survival but not with overall survival. Conclusion: This study confirms the prognostic value of the combined expression of BUB1B, DLGAP5, and PINK1 genes in a Brazilian group of adult ACTs. Among pediatric ACTs, other molecular predictors of outcome are required.

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The hydroponic cultivation of vegetables has increased markedly in recent years, however, little is known about its chemical composition, which is of extreme importance in view of changing food habits of a considerable fraction of the population seeking food quality. For this reason, cultivation of watercress, chicory, rocket and lettuce American (Lucy Brown) and smooth (cv. Regina) were grown in hydroponics, NFT system, aiming to evaluate the yield, nitrate content and chemical composition. The experiment was conducted in a greenhouse at the Universidade Federal de Santa Catarina, Florianopolis city in the Santa Catarina State (Brazil), from may to july 2004 under a completely randomized design with four replications. The spacing used was 25 x 25 cm for the crops of watercress, chicory and lettuce (cv. Lucy Brown and cv. Regina) and 5 x 5 cm to the rocket. The traits were: number of leaves, nitrate content and chemical composition of vegetables. The lettuce cv. Regina and chicory had higher number of leaves per plant. The watercress had lower water content and higher dry mass of shoots. The largest increase in fresh weight was obtained in chicory, lettuce, cv. Regina. Higher levels of lipids, protein, ash, carbohydrates, calories, fiber and nitrate were obtained from the watercress. The rocket had lower values for the variables fresh and dries the whole plant, shoot and root and leaf number per plant. All cultures showed good visual appearance, low calorie and nitrate levels suitable for human consumption.

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The purpose of this study was to evaluate the antioxidant activity of honey from different entomological sources which were harvested in the dry season of 2008-2009 from distinct mesoregions of the State of Alagoas in the North East of Brazil. Honey produced by five different species of bees, even from the same region and season, showed a statistically significant difference (p <0.05) in the content of phenols, flavonoids and antioxidants, with higher levels of these compounds found in honey produced by Plebeia spp. and A. mellifera. Honey from stingless bees was quite different from that of A. mellifera, especially from the Plebeia spp. A dendrogram of the five species of bees showed the formation of 3 groups, one being formed by Apis mellifera, one by the genus Melipona (M. subnitida, M. quadrifasciata and M. scutellaris) and another formed by Plebeia spp.

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Abstract Background Gyr cows are well adapted to tropical conditions, resistant to some tropical diseases and have satisfactory milk production. However, Gyr dairy herds have a high prevalence of subclinical mastitis, which negatively affects their milk yield and composition. The objectives of this study were (i) to evaluate the effects of seasonality, mammary quarter location (rear x front), mastitis-causing pathogen species, and somatic cell count (SCC) on milk composition in Gyr cows with mammary quarters as the experimental units and (ii) to evaluate the effects of seasonality and somatic cell count (SCC) on milk composition in Gyr cows with cows as the experimental units. A total of 221 lactating Gyr cows from three commercial dairy farms were selected for this study. Individual foremilk quarter samples and composite milk samples were collected once a month over one year from all lactating cows for analysis of SCC, milk composition, and bacteriological culture. Results Subclinical mastitis reduced lactose, nonfat solids and total solids content, but no difference was found in the protein and fat content between infected and uninfected quarters. Seasonality influenced milk composition both in mammary quarters and composite milk samples. Nevertheless, there was no effect of mammary quarter position on milk composition. Mastitis-causing pathogens affected protein, lactose, nonfat solids, and total solids content, but not milk fat content. Somatic cell count levels affected milk composition in both mammary quarters and composite samples of milk. Conclusions Intramammary infections in Gyr cows alter milk composition; however, the degree of change depends on the mastitis-causing pathogen. Somatic cell count is negatively associated with reduced lactose and nonfat solids content in milk. Seasonality significantly affects milk composition, in which the concentration of lactose, fat, protein, nonfat solids and total solids differs between dry and wet seasons in Gyr cows.

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Intense phytoplankton blooms were observed along the Patagonian shelf-break with satellite ocean color data, but few in situ optical observations were made in that region. We examine the variability of phytoplankton absorption and particulate scattering coefficients during such blooms on the basis of field data. The chlorophyll-a concentration, [Chla], ranged from 0.1 to 22.3 mg m−3 in surface waters. The size fractionation of [Chla] showed that 80% of samples were dominated by nanophytoplankton (N-group) and 20% by microphytoplankton (M-group). Chlorophyll-specific phytoplankton absorption coefficients at 440 and 676 nm, a*ph(440) and a*ph(676), and particulate scattering coefficient at 660 nm, b*p(660), ranged from 0.018 to 0.173, 0.009 to 0.046, and 0.031 to 2.37 m2 (mg Chla)−1, respectively. Both a*ph(440) and a*ph(676) were statistically higher for the N-group than M-group and also considerably higher than expected from global trends as a function of [Chla]. This result suggests that size of phytoplankton cells in Patagonian waters tends to be smaller than in other regions at similar [Chla]. The phytoplankton cell size parameter, Sf, derived from phytoplankton absorption spectra, proved to be useful for interpreting the variability in the data around the general inverse dependence of a*ph(440), a*ph(676), and b*p(660) on [Chla]. Sf also showed a pattern along the increasing trend of a*ph(440) and a*ph(676) as a function of the ratios of some accessory pigments to [Chla]. Our results suggest that the variability in phytoplankton absorption and scattering coefficients in Patagonian waters is caused primarily by changes in the dominant phytoplankton cell size accompanied by covariation in the concentrations of accessory pigments.