71 resultados para Time in narrative
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Rangel EM, Mendes IA, Carnio EC, Marchi Alves LM, Godoy S, Crispim JA. Development, implementation, and assessment of a distance module in endocrine physiology. Adv Physiol Educ 34: 70-74, 2010; doi: 10.1152/advan.00070.2009.-This study aimed to develop, implement, and assess a distance module in endocrine physiology in TelEduc for undergraduate nursing students from a public university in Brazil, with a sample size of 44 students. Stage 1 consisted of the development of the module, through the process of creating a distance course by means of the Web. Stage 2 was the planning of the module's practical functioning, and stage 3 was the planning of student evaluations. In the experts' assessment, the module complied with pedagogical and technical requirements most of the time. In the practical functioning stage, 10 h were dedicated for on-site activities and 10 h for distance activities. Most students (93.2%) were women between 19 and 23 yr of age (75%). The internet was the most used means to remain updated for 23 students (59.0%), and 30 students (68.2%) accessed it from the teaching institution. A personal computer was used by 23 students (56.1%), and most of them (58.1%) learned to use it alone. Access to a forum was more dispersed (variation coefficient: 86.80%) than access to chat (variation coefficient: 65.14%). Average participation was 30 students in forums and 22 students in the chat. Students' final grades in the module averaged 8.5 (SD: 1.2). TelEduc was shown to be efficient in supporting the teaching- learning process of endocrine physiology.
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The present work evaluated rickettsial infection in dogs and their ticks in an area endemic for Brazilian spotted fever (BSF) in the metropolitan area of Sao Paulo, Brazil, where the tick Amblyomma aureolatum was presumed to be the vector of the disease. Ticks were collected on dogs from 185 houses, encompassing single infestations by Rhipicephalus sanguineus, Amblyomma aureolatum, Amblyomma longirostre, or Amblyomma sp. in dogs from 60 (32.4%), 77 (41.6%), 2 (1.1%), and 25 (13.5%) houses, respectively; 19 (10.3%) houses had dogs with mixed infestations by R. sanguineus and A. aureolatum; 1 (0.5%) house had dogs with infestations by A. aureolatum and A. longirostre; and 1 (0.5%) house had dogs with infestations by R. sanguineus and Amblyomma sp. Overall, A. aureolatum was present in dogs from 97 (52.4%) houses, and R. sanguineus in dogs from 80 (43.2%) houses. A total of 287 ticks (130 A. aureolatum and 157 R. sanguineus) infesting dogs from 98 houses were selected for testing by polymerase chain reaction (PCR) targeting rickettsial genes. Overall, 3.1% of the A. aureolatum ticks were infected by Rickettsia bellii, and 1.3% of the R. sanguineus were infected by Ricketttsii rickettsii. For serology, we selected 23 dogs living in and in the vicinity of the house where the R. rickettsii-infected ticks were collected. The indirect fluorescent antibody (IFA) test detected antibodies reactive with R. rickettsii in sera from 16 (69.6%) dogs, with titers ranging from 256 to 32,768. It is established that Amblyomma aureolatum is a vector of R. rickettsii in the Sao Paulo metropolitan area, but our results highlight for the first time in Brazil, a possible role of R. sanguineus in the epidemiology of R. rickettsii, corroborating previous findings in Mexico and the United States, where R. sanguineus has been implicated in the transmission of R. rickettsii to humans.
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Background: The establishment of an in vitro production (IVP) of embryo in swine allows the generation of embryos with the same quality as in vivo produced embryos with less costs and time. In order to achieve successful fertilization under normal circumstances in vivo, mammalian spermatozoa must first undergo capacitation and then acrosome reaction. The purpose of this study was compared the efficacious of IP/CFDA fluorescence and Coomassie Blue G (CB) staining to detect capacitated sperm cells in refrigerated and fresh semen. Morever, it was investigated the efficacious of caffeine and chondroitin sulphate to promote in vitro sperm capacitation and in vitro embryo produced (IVP) of swine embryos. Materials, Methods & Results: A sperm-rich fraction from ejaculate was obtained using the gloved-hand method and the gel-free fraction was separated using sterile gauze. The semen was diluted in BTS at a final concentration of 1.5 x 10(8) cells/mL. The sperm suspension was incubated for 2 h at 25 degrees C, refrigerated and maintained for 1 h at 15-18 degrees C (refrigerated group) or used immediately (fresh group). Sperm capacitation was assessed by IP/CFDA fluorescence and CB staining for both fresh and refrigerated semen. For PI/CFDA evaluation, a final solution containing 1.7 mM formaldehyde, 7.3 mM PI and 20 mM CFDA in 950 mu L saline was prepared. In the dark, 40 mu L PI/CFDA final solution was added to 10 mu L semen and after 8 min, slides were analyzed on epifluorescence microscopy. For CB evaluation, sperm cells were fixed in 4% paraformaldehyde for 10 min and centrifuged twice at 320 x g in ammonium acetate pH 9 for 8 min. A smear was made and stained with 2.75 mg/mL CB in solution containing 12.5% methanol, 25% glacial acetic acid and 62.5% water, for 2 min. The smear was washed in running water, air dried and sealed with Permount (R), diluted 2:1 in xilol to avoid staining oxidation. Our results showed that refrigeration did not affect sperm capacitation and comparing staining methods, the PI/CFDA combination was more efficient to detect capacitated sperm, when compared to CB staining. In experiment 2, we evaluated the effect of different incubation time (1 - 5 h) with chondroitin sulfate and caffeine on sperm capacitation. For in vitro fertilization, oocytes were obtained from slaughterhouse ovaries. Oocytes with a thick and intact cumulus oophurus layer and cytoplasm with homogenous granules were selected for in vitro maturation for 44 h. According to the results of experiment 2, it was used for in vitro fertilization refrigerated semen was capacitated with 50 mu g/mL chondroitin sulfate for 2 h or capacitated with 5 mu g/mL caffeine for 3 h. Six hours after insemination, cumulus oophorus cells were mechanically removed and oocytes were washed and incubated in microdrops of culture medium. Embryo development after fertilization with sperm capacitated with caffeine or chondroitin sulfate was evaluated on days 3, 5 and 7 of culture. No differences were observed in days 3 or 5 of in vitro culture. However, it was observed an increase on blastocyst rate on Day 7 of culture when caffeine was used as the capacitor agent. Discussion: Molecular basis of sperm capacitation is still poor understood. Sperm capacitation can occur in vitro spontaneously in defined media without addition of biological fluids. We observed that sperm capacitation increased as incubation period enlarged and it was observed using Coomassie blue G and PI/CFDA for fresh semen and for refrigerated semen. It can be concluded that the cooling of semen did not change their pattern of sperm capacitation and this is best assessed by IP/CFDA than by CB. In addition to the use of caffeine in sperm capacitation produces more blastocysts than the chondroitin sulfate after in vitro fertilization.
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The purpose of this study was to assess the benefits of using e-learning resources in a dental training course on Atraumatic Restorative Treatment (ART). This e-course was given in a DVD format, which presented the ART technique and philosophy. The participants were twenty-four dentists from the Brazilian public health system. Prior to receiving the DVD, the dentists answered a questionnaire regarding their personal data, previous knowledge about ART, and general interest in training courses. The dentists also participated in an assessment process consisting of a test applied before and after the course. A single researcher corrected the tests, and intraexaminer reproducibility was calculated (kappa=0.89). Paired t-tests were carried out to compare the means between the assessments, showing a significant improvement in the performance of the subjects on the test taken after the course (p<0.05). A linear regression model was used with the difference between the means as the outcome. A greater improvement on the test results was observed among female dentists (p=0.034), dentists working for a shorter period of time in the public health system (p=0.042), and dentists who used the ART technique only for urgent and/or temporary treatment (p=0.010). In conclusion, e-learning has the potential of improving the knowledge that dentists working in the public health system have about ART, especially those with less clinical experience and less knowledge about the subject.
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Synoptic spectroscopic observations of the U Sco 2010 outburst from maximum light to quiescence as well as a contemporaneous X-ray observation are presented and analyzed. The X-ray spectrum 52 days after outburst indicates a hot source ( kT(bb) similar to 70 eV). Narrow-line components from the irradiated companion atmosphere were observed in hydrogen and helium optical recombination lines. The formation of a nebular spectrum is seen for the first time in this class of recurrent novae, allowing a detailed study of the ejecta using photoionization models. Unusual [O III] auroral-to-nebular line ratios were found and possible scenarios of their origin are discussed. The modeling of the emission line spectrum suggests highly heterogeneous ejecta with masses around or above 3 x 10(-6) M(sun).
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The longitudinal spin transfer, D(LL), from high energy polarized protons to Lambda and Lambda hyperons has been measured for the first time in proton-proton collisions at s=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. The measurements cover pseudorapidity, eta, in the range |eta|< 1.2 and transverse momenta, p(T), up to 4 GeV/c. The longitudinal spin transfer is found to be D(LL)=-0.03 +/- 0.13(stat)+/- 0.04(syst) for inclusive Lambda and D(LL)=-0.12 +/- 0.08(stat)+/- 0.03(syst) for inclusive Lambda hyperons with <
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This study investigated the energy system contributions of rowers in three different conditions: rowing on an ergometer without and with the slide and rowing in the water. For this purpose, eight rowers were submitted to 2,000 m race simulations in each of the situations defined above. The fractions of the aerobic (W(AER)), anaerobic alactic (W(PCR)) and anaerobic lactic (W([La-])) systems were calculated based on the oxygen uptake, the fast component of excess post-exercise oxygen uptake and changes in net blood lactate, respectively. In the water, the metabolic work was significantly higher [(851 (82) kJ] than during both ergometer [674 (60) kJ] and ergometer with slide [663 (65) kJ] (P <= 0.05). The time in the water [515 (11) s] was higher (P < 0.001) than in the ergometers with [398 (10) s] and without the slide [402 (15) s], resulting in no difference when relative energy expenditure was considered: in the water [99 (9) kJ min(-1)], ergometer without the slide [99.6 (9) kJ min(-1)] and ergometer with the slide [100.2 (9.6) kJ min(-1)]. The respective contributions of the WAER, WPCR and W[La-] systems were water = 87 (2), 7 (2) and 6 (2)%, ergometer = 84 (2), 7 (2) and 9 (2)%, and ergometer with the slide = 84 (2), 7 (2) and 9 (1)%. (V) over dotO(2), HR and lactate were not different among conditions. These results seem to indicate that the ergometer braking system simulates conditions of a bigger and faster boat and not a single scull. Probably, a 2,500 m test should be used to properly simulate in the water single-scull race.
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Recent findings have indicated that creatine supplementation may affect glucose metabolism. This study aimed to examine the effects of creatine supplementation, combined with aerobic training, on glucose tolerance in sedentary healthy male. Subjects (n = 22) were randomly divided in two groups and were allocated to receive treatment with either creatine (CT) (similar to 10g .day over three months) or placebo (PT) (dextrose). Administration of treatments was double blind. Both groups underwent moderate aerobic training. An oral glucose tolerance test (OGTT) was performed and both fasting plasma insulin and the homeostasis model assessment (HOMA) index were assessed at the start, and after four, eight and twelve weeks. CT demonstrated significant decrease in OGTT area under the curve compared to PT (P = 0.034). There were no differences between groups or over time in fasting insulin or HOMA. The results suggest that creatine supplementation, combined with aerobic training, can improve glucose tolerance but does not affect insulin sensitivity, and may warrant further investigation with diabetic subjects.
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An accurate estimate of machining time is very important for predicting delivery time, manufacturing costs, and also to help production process planning. Most commercial CAM software systems estimate the machining time in milling operations simply by dividing the entire tool path length by the programmed feed rate. This time estimate differs drastically from the real process time because the feed rate is not always constant due to machine and computer numerical controlled (CNC) limitations. This study presents a practical mechanistic method for milling time estimation when machining free-form geometries. The method considers a variable called machine response time (MRT) which characterizes the real CNC machine`s capacity to move in high feed rates in free-form geometries. MRT is a global performance feature which can be obtained for any type of CNC machine configuration by carrying out a simple test. For validating the methodology, a workpiece was used to generate NC programs for five different types of CNC machines. A practical industrial case study was also carried out to validate the method. The results indicated that MRT, and consequently, the real machining time, depends on the CNC machine`s potential: furthermore, the greater MRT, the larger the difference between predicted milling time and real milling time. The proposed method achieved an error range from 0.3% to 12% of the real machining time, whereas the CAM estimation achieved from 211% to 1244% error. The MRT-based process is also suggested as an instrument for helping in machine tool benchmarking.
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Many lab-scale studies have been carried out regarding the effect of feed strategy on the performance of anaerobic sequencing batch reactors (ASBR); however, more detailed pilot-scale studies should be performed to assess the real applicability of this type of operation. Therefore, the objective of this work was to assess the effect of feed strategy or fill time in a 1-m(3) mechanically stirred pilot-scale sequencing batch reactor, treating 0.65 m(3) sanitary wastewater in 8-h cycles at ambient temperature. Two reactor configurations were used: one containing granular biomass (denominated ASBR) and the other immobilized biomass on polyurethane foam as inert support (denominated anaerobic sequencing batch biofilm reactor (AnSBBR)). The reactors were operated under five distinct feed strategies, namely: typical batch and fed-batch for 25%, 50%, 75%, and 100% of the cycle length. Stirring frequency in the ASBR was 40 rpm with two flat-blade turbine impellers and 80 rpm in the AnSBBR with two helix impellers. The results showed that both the ASBR and AnSBBR when operated under typical batch, fed-batch for 50% and 75% of the cycle length, presented improved organic matter removal efficiencies, without significant differences in performance, thus showing important operational flexibility. In addition, the reactors presented operation stability under all conditions.
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This paper aims to investigate the influence of some dissolved air flotation (DAF) process variables (specifically: the hydraulic detention time in the contact zone and the supplied dissolved air concentration) and the pH values, as pretreatment chemical variables, on the micro-bubble size distribution (BSD) in a DAF contact zone. This work was carried out in a pilot plant where bubbles were measured by an appropriate non-intrusive image acquisition system. The results show that the obtained diameter ranges were in agreement with values reported in the literature (10-100mm), quite independently of the investigated conditions. The linear average diameter varied from 20 to 30mm, or equivalently, the Sauter (d(3,2)) diameter varied from 40 to 50mm. In all investigated conditions, D(50) was between 75% and 95%. The BSD might present different profile (with a bimodal curve trend), however, when analyzing the volumetric frequency distribution (in some cases with the appearance of peaks in diameters ranging from 90-100mm). Regarding volumetric frequency analysis, all the investigated parameters can modify the BSD in DAF contact zone after the release point, thus potentially causing changes in DAF kinetics. This finding prompts further research in order to verify the effect of these BSD changes on solid particle removal efficiency by DAF.
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In all-optical networks, management of physical layer restrictions should collaborate in lightpath establishment. Label-Switched Path validation in Generalized MultiProtocol Label Switching on Dense Wavelength Division Multiplexing network requires the treatment of the physical impairment-related parameters along the provisioned route. In this paper we propose, for the first time in our view, the generation of an optical layer database by simulation that specifically characterizes the dynamic FWM impairments for the lightpaths provisioned in a GMPLS/DWDM network.
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In contrast with the abundance of anatomical studies of secretory structures on aerial vegetative organs of Asteraceae species, the information about secretory structures on thickened subterranean organs is sparse. The aim of this study was to investigate the occurrence of secretory structures on thickened and nonthickened subterranean organs of seven Asteraceae species from three tribes: Eupatorieae (Chromolaena squalida and Gyptis lanigera), Vernonieae (Chresta sphaerocephala, Lessingianthus bardanoides, L. glabratus and Orthopappus angustifolius), and Plucheeae (Pterocaulon angustifolium). The specimens were collected in areas of cerrado, from the State of Sao Paulo, Brazil. All species of the tribe Vernonieae studied exhibited endodermic cells, other than the epithelial cells of the canal, with secretory activity in the roots. In C. sphaerocephala roots, two types of endodermic cell were found, but only one had secretory activity. Secretory canals were found in the tuberous and nontuberous roots of all studied species. These data agree with the results from the literature for Asteraceae species. Here, we describe for the first time in Asteraceae the presence of secretory idioblasts in C. sphaerocephala. Secretory trichomes are present in the Orthopappus angustifolius rhizophore. Histochemical tests have shown that all types of secretory structure possess substances containing lipids. (C) 2008 The Linnean Society of London.
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Sorption-desorption interactions of pesticides with soil determine their availability for transport, plant uptake, and microbial degradation. These interactions are affected by the physical-chemical properties of the pesticide and soil, and for some pesticides, their residence time in the soil. This research evaluated changes in sorption/availability of nicosulfuron (2-[[[[(4,6-dimethoxy-2-pyrimidinyl]aminolcarbonyl]amino]sulfonyl]-N,N-dimethyl-3-pyridinecarboxamide) herbicide with aging in different soils, using a radiolabeled (C-14) tracer. Aging significantly increased sorption. For instance, after the 41-day incubation, calculated K-d,K-app increased by a factor of 2 to 3 in Mollisols from the Midwestern United States and by a factor of 5 to 9 in Oxisols from Brazil and Hawaii, as compared to freshly treated soils. In view of this outcome, potential transport of nicosulfuron would be overpredicted if freshly treated soil Kd values were used to predict transport. The fact that the nicosulfuron solution concentration decreased faster than the soil concentration with time suggested that the increase in sorption was because the rate of degradation in solution and on labile sites was faster than the rate of desorption of the neutral species from the soil particles. It may have also been due to nicosulfuron anion diffusion to less accessible sites with time, leaving the more strongly bound neutral molecules for the sorption characterization. Regardless of the mechanism, these results are further evidence that increases in sorption during pesticide aging should be taken into account during the characterization of the sorption process for mathematical models of pesticide degradation and transport.
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Pseudocercospora griseola (Sacc.) Crous &. Braun is a widespread fungal phytopathogen that is responsible for angular leaf spot in the common bean (Phaseolus vulgaris L.). A number of fungal phytopathogens have been shown to harbour mycoviruses, and this possibility was investigated in populations of Pseudocercospora griseola. The total nucleic acid extracts of 61 fungal isolates were subjected to agarose gel electrophoresis. Small fragments (800-4800 bp) could be identified in 42 of the samples. The presence of dsRNA in isolate Ig838 was confirmed by treatment of total nucleic acid with DNase, RNase A, and nuclease S I. Transmission electron microscopy revealed the presence of viral-like particles 40 nm in diameter in the mycelia of 2 fungal isolates, namely 29-3 and Ig838. The transmission of dsRNA by means of conidia was 100% for isolate 29-3, but there was loss of 1-6 fragments of dsRNA in monosporic colonies of isolate Ig848. Cycloheximide treatment failed to inhibit the mycovirus in isolate 29-3, but proved efficient in the elimination of the 2.2, 2.0, 1.8, 1.2 and 1.0 kb fragments in 2 colonies of isolate Ig848. The occurrence of a mycovirus in Pseudocercospora griseola was demonstrated for the first time in the present study.