930 resultados para Spot sizes


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This paper describes the development and application of a simple, cheap, and clean method for the quantification of furosemide in urine samples from athletes, to detect doping, using a combined spot test/diffuse reflectance spectroscopy procedure. The method is based on the complexation reaction of furosemide (5-(aminosulfonyl)-4-chloro-2-((furanylmethyl)amino)benzoic acid, dissolved in ethanol, with FeCl3 and the surfactant dodecyltrimethylammonium bromide (DTAB) in aqueous solution, yielding a colored compound on the surface of a filter paper. The reagent concentrations were optimized using a chemometric experimental design. The reflectometric measurements of the complex formed were carried out at 477nm. The linear range obtained was 1.65-9.00×10-3molL-1 of furosemide (R=0.997), and the detection and quantification limits were 4.9×10-4 and 1.62×10-3molL-1, respectively. The proposed method was successfully applied in the analysis of furosemide in spiked urine, demonstrating that it is a reliable alternative method for the detection of furosemide doping in sport. © 2012 Elsevier B.V..

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The aim of this study was to evaluate the stress distribution in implants of regular platforms and of wide diameter with different sizes of hexagon by the 3-dimensional finite element method. We used simulated 3-dimensional models with the aid of Solidworks 2006 and Rhinoceros 4.0 software for the design of the implant and abutment and the InVesalius software for the design of the bone. Each model represented a block of bone from the mandibular molar region with an implant 10 mm in length and different diameters. Model A was an implant 3.75 mm/regular hexagon, model B was an implant 5.00 mm/regular hexagon, and model C was an implant 5.00 mm/ expanded hexagon. A load of 200 N was applied in the axial, lateral, and oblique directions. At implant, applying the load (axial, lateral, and oblique), the 3 models presented stress concentration at the threads in the cervical and middle regions, and the stress was higher for model A. At the abutment, models A and B showed a similar stress distribution, concentrated at the cervical and middle third; model C showed the highest stresses. On the cortical bone, the stress was concentrated at the cervical region for the 3 models and was higher for model A. In the trabecular bone, the stresses were less intense and concentrated around the implant body, and were more intense for model A. Among the models of wide diameter (models B and C), model B (implant 5.00 mm/regular hexagon) was more favorable with regard to distribution of stresses. Model A (implant 3.75 mm/regular hexagon) showed the largest areas and the most intense stress, and model B (implant 5.00 mm/regular hexagon) showed a more favorable stress distribution. The highest stresses were observed in the application of lateral load.

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This study analyzed the spatial distribution of Yellow Sigatoka Leaf Spot relative to soil fertility and plant nutritional status using geostatistics. The experimental area comprised 1.2 ha, where 27 points were georeferenced and spaced on a regular grid 18 × 18 m. The severity of Yellow Sigatoka, soil fertility and plant nutritional status were evaluated at each point. The spherical model was adjusted for all variables using restricted maximum likelihood. Kriging maps showed the highest infection rate of Sigatoka occurred in high areas of the field which had the highest concentration of sand, while the lowest disease was found in lower areas with lower silt, organic matter, total exchangeable bases, effective cation exchange capacity, base saturation, Ca and Mg in soil, and foliar sulfur (S). These results may help farmers manage Yellow Sigatoka disease more effectively, with balanced fertilization and reduced fungicide application. This practice minimizes the environmental impact and cost of production while contributing to production sustainability.

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A plant’s nutritional balance can influence its resistance to diseases. In order to evaluate the effect of increasing doses of N and K on the yield and severity of the maize white spot, two experiments were installed in the field, one in the city of Ijaci, Minas Gerais, and the other in the city of Sete Lagoas, Minas Gerais. The experimental delimitation was in randomized blocks with 5 x 5 factorial analysis of variance, and four repetitions. The treatments consisted of five doses of N (20; 40; 80; 150; 190 Kg ha-1 of N in the experiments 1 and 2) and five doses of K (15; 30; 60; 120; 180 Kg ha-1 of K in experiment 1 and 8.75; 17.5; 35; 50; 100 Kg ha-1 of K in experiment 2). The susceptible cultivar 30P70 was planted in both experiments. The plot consisted of four rows 5 meters long, with a useful area consisting of two central rows 3 meters each. Evaluations began 43 days after emergence (DAE) in the first experiment and 56 DAE in the second one. There was no significant interaction between doses of N and K and the disease progress. The effect was only observed for N. The K did not influence the yield and the severity of the disease in these experiments. Bigger areas below the severity progress curve of the white spot and better yield were observed with increasing doses of N. Thus, with increasing doses of N, the white spot increased and also did the yield.

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O objetivo deste trabalho foi avaliar os efeitos do aumento da concentração de CO2 do ar sobre o crescimento de plantas e sobre a mancha foliar causada por Cylindrocladium candelabrum em Eucalyptus urophylla. As mudas foram cultivadas durante 30 dias, a 451, 645, 904, 1.147 µmol mol-1 de CO2 ; em seguida, elas foram inoculadas com o patógeno e mantidas nas mesmas condições por sete dias. O aumento da concentração de CO2 aumentou a altura de plantas e a massa de matéria seca da parte aérea, e diminuiu a incidência e a severidade da doença. O diâmetro do caule não foi afetado pelos tratamentos. O aumento das concentrações de CO2 atmosférico afeta favoravelmente o crescimento de plântulas de eucalipto e reduz a severidade da mancha foliar.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The desert locust (Schistocerca gregaria) has been used as material for numerous cytogenetic studies. Its genome size is estimated to be 8.55 Gb of DNA comprised in 11 autosomes and the X chromosome. Its X0/XX sex chromosome determinism therefore results in females having 24 chromosomes whereas males have 23. Surprisingly, little is known about the DNA content of this locust's huge chromosomes. Here, we use the Feulgen Image Analysis Densitometry and C-banding techniques to respectively estimate the DNA quantity and heterochromatin content of each chromosome. We also identify three satellite DNAs using both restriction endonucleases and next-generation sequencing. We then use fluorescent in situ hybridization to determine the chromosomal location of these satellite DNAs as well as that of six tandem repeat DNA gene families. The combination of the results obtained in this work allows distinguishing between the different chromosomes not only by size, but also by the kind of repetitive DNAs that they contain. The recent publication of the draft genome of the migratory locust (Locusta migratoria), the largest animal genome hitherto sequenced, invites for sequencing even larger genomes. S. gregaria is a pest that causes high economic losses. It is thus among the primary candidates for genome sequencing. But this species genome is about 50 % larger than that of L. migratoria, and although next-generation sequencing currently allows sequencing large genomes, sequencing it would mean a greater challenge. The chromosome sizes and markers provided here should not only help planning the sequencing project and guide the assembly but would also facilitate assigning assembled linkage groups to actual chromosomes.

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In this work, crystalline titanium dioxide (TiO2) nanoparticles with variable average crystallite sizes (e.g., 8 nm) and surface areas (e.g., 192 m² g-1) were synthesized in pure anatase phase using H2O2 to reduce the hydrolysis rate of the titanium ions. An isopropanol (IP) solution was employed as the reaction medium. The TiO2 nanoparticles were characterized by powder X-ray diffraction analysis (XRD), Raman spectroscopy and transmission electron microscopy (TEM). By changing the synthesis parameters it was possible to control nanoparticle size and avoid the coalescence process. A dependence of the Raman wavenumber on the nanocrystal sizes was determined, which is quite useful for a quick check of the size of TiO2 nanocrystals.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Adult specimens of the spot. Leiostomus xanthurus, were collected from bayou, Mississippi Sound, and barrier island locations along the Gulf Coast of Mississippi from November 1982 to July 1989. 7he mean total length of all spot sampled in comparable gill net sets was 219 mm (± 14 standard deviation, n=4,338). Ninety-five percent of the spot were collected in the island and sound areas, where the salinity was higher than in the bayous. Catch per unit effort was high at island and sound stations in spring and autumn, with relatively few fish caught during the winter spawning season and summer. The relatively high frequency of spot observed at the island stations in the autumn was probably influenced by spawning migrations, and the high spring values may represent a combination of two abundant year classes. The two greatest yearly collections, in 1983 and 1986, may have been influenced by sampling conditions or by environmental conditions favorable to survival either during those years or earlier when those fish were postlarvae. The smallest yearly catch occurred in 1985 and may have reflected the harsh weather conditions that year.

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Factor analysis was used to develop a more detailed description of the human hand to be used in the creation of glove sizes; currently gloves sizes are small, medium, and large. The created glove sizes provide glove designers with the ability to create a glove design that can provide fit to the majority of hand variations in both the male and female populations. The research used the American National Survey (ANSUR) data that was collected in 1988. This data contains eighty-six length, width, height, and circumference measurements of the human hand for one thousand male subjects and thirteen hundred female subjects. Eliminating redundant measurements reduced the data to forty-six essential measurements. Factor analysis grouped the variables to form three factors. The factors were used to generate hand sizes by using percentiles along each factor axis. Two different sizing systems were created. The first system contains 125 sizes for male and female. The second system contains 7 sizes for males and 14 sizes for females. The sizing systems were compared to another hand sizing system that was created using the ANSUR database indicating that the systems created using factor analysis provide better fit.

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The 3PL model is a flexible and widely used tool in assessment. However, it suffers from limitations due to its need for large sample sizes. This study introduces and evaluates the efficacy of a new sample size augmentation technique called Duplicate, Erase, and Replace (DupER) Augmentation through a simulation study. Data are augmented using several variations of DupER Augmentation (based on different imputation methodologies, deletion rates, and duplication rates), analyzed in BILOG-MG 3, and results are compared to those obtained from analyzing the raw data. Additional manipulated variables include test length and sample size. Estimates are compared using seven different evaluative criteria. Results are mixed and inconclusive. DupER augmented data tend to result in larger root mean squared errors (RMSEs) and lower correlations between estimates and parameters for both item and ability parameters. However, some DupER variations produce estimates that are much less biased than those obtained from the raw data alone. For one DupER variation, it was found that DupER produced better results for low-ability simulees and worse results for those with high abilities. Findings, limitations, and recommendations for future studies are discussed. Specific recommendations for future studies include the application of Duper Augmentation (1) to empirical data, (2) with additional IRT models, and (3) the analysis of the efficacy of the procedure for different item and ability parameter distributions.