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| Registros recuperados: 46 | |
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| Doglioli, Andrea; Nencioli, Francesco; Petrenko, Anne; Rougier, Gilles; Fuda, Jean-luc; Grima, Nicolas. |
| The Lagrangian Transport Experiment (LATEX) was developed to study the influence of coupled physical and biogeochemical dynamics at the meso- and submesoscales on the transfers of matter and heat between the coastal zone and the open ocean. One of the goals of the Latex10 field experiment, conducted during September 2010 in the Gulf of Lion (northwest Mediterranean), was to mark a dynamical mesoscale feature by releasing a passive tracer [sulfur hexafluoride (SF6)] together with an array of Lagrangian buoys. The goal was to release the tracer in an initial patch as homogeneous as possible in the horizontal, and to study its turbulent mixing and dispersion while minimizing the contribution due to advection. For that, it was necessary to continuously adjust... |
| Tipo: Text |
Palavras-chave: Dispersion; Lagrangian circulation; Transport; Ship observations; Tracers; Experimental design; Software. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00155/26590/24719.pdf |
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| Hahn, Jinyong; Hirano, Keisuke; Karlan, Dean S.. |
| Many social experiments are run in multiple waves, or are replications of earlier social experiments. In principle, the sampling design can be modified in later stages or replications to allow for more efficient estimation of causal effects. We consider the design of a two-stage experiment for estimating an average treatment effect, when covariate information is available for experimental subjects. We use data from the first stage to choose a conditional treatment assignment rule for units in the second stage of the experiment. This amounts to choosing the propensity score, the conditional probability of treatment given covariates. We propose to select the propensity score to minimize the asymptotic variance bound for estimating the average treatment... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Experimental design; Propensity score; Efficiency bound; Research Methods/ Statistical Methods; C1; C14; C9; C93; C13. |
| Ano: 2009 |
URL: http://purl.umn.edu/47107 |
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| Donis, Daphne; Holtappels, Moritz; Noss, Christian; Cathalot, Cecile; Hancke, Kasper; Polsenaere, Pierre; Wenzhoefer, Frank; Lorke, Andreas; Meysman, Filip J. R.; Glud, Ronnie N.; Mcginnis, Daniel F.. |
| The quantification of benthic fluxes with the aquatic eddy correlation (EC) technique is based on simultaneous measurement of the current velocity and a targeted bottom water parameter (e.g., O2, temperature). High-frequency measurements (64 Hz) are performed at a single point above the seafloor using an acoustic Doppler velocimeter (ADV) and a fast-responding sensor. The advantages of aquatic EC technique are that 1) it is noninvasive, 2) it integrates fluxes over a large area, and 3) it accounts for in situ hydrodynamics. The aquatic EC has gained acceptance as a powerful technique; however, an accurate assessment of the errors introduced by the spatial alignment of velocity and water constituent measurements and by their different response times is... |
| Tipo: Text |
Palavras-chave: Turbulence; Boundary layer; Fluxes; Instrumentation/sensors; Optimization; Experimental design. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00275/38577/37102.pdf |
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| Molin,Rochele Fernanda; Valduga,Alice Teresa; Di Luccio,Marco; Dartora,Nessana; Cichoski,Alexandre José; Pistore,Mônica; Rigo,Elisandra. |
| This work aimed to study the oxidation of leaves of Ilex paraguariensis St. Hil, in a process similar to the oxidation of Camellia sinensis, with the purpose of developing new products based on yerba maté. So far, no previous systematic study about the oxidation of yerba maté has been found elsewhere. A Plackett-Burman experimental design was used for the screening of the significant parameters that affected the oxidation. The oxidation was indirectly quantified by following the changes in the product color, water activity, and pH with the time of processing. The factors that most influenced the process were the age of the leaves and the relative humidity of the oxidation chamber. The differences between the treatments were more evident after 3, 6 12 and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Physicochemical parameters; Yerba maté; Leave; Extract; Experimental design. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000200016 |
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| Cârcu-Dobrin,Melania; Sabău,Alexandra Georgiana; Hancu,Gabriel; Árpád,Gyéresi; Rusu,Aura; Kelemen,Hajnal; Papp,Lajos Attila; Cârje,Anca. |
| The present work describes the development of a capillary electrophoresis (CE) method for the chiral discrimination of amlodipine (AML) enantiomers using cyclodextrine (CD) derivatives as chiral selectors. A large number of native and derivatized, neutral and ionized CD derivatives were screened to find the optimal chiral selector; and carboximethyl-β-CD (CM-β-CD) was selected for the enantiomeric discrimination. A factorial analysis study was performed by orthogonal experimental design in which several factors were varied at the same time to optimize the separation method. The optimized method (25 mM phosphate buffer, pH = 9.0, 15 mM CM-β-CD, 15 ºC, + 25 kV, 30 mbar/1 second, detection wavelength 230 nm) was successfully applied for the baseline... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amlodipine; Capillary electrophoresis; Chiral separation; Cyclodextrine; Experimental design. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502020000100530 |
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| Carvalho,Agnaldo DF; Silva,Giovani O. |
| ABSTRACT The square lattice 4x4 design was compared to a randomized block design, for carrot F1 hybrids. Sixteen experimental carrot hybrids were evaluated in Brasília, in 2014/15 and 2015/16 agricultural years. A square lattice 4x4 design with three replications was used. The experimental plot consisted of 1.5 m2 useful area. The experimental area was installed on the second half of November 2014 and 2015. Cultural practices were the usually given to the carrot crop in Brazilian savannah region. The incidence of leaf blight was evaluated 90 days after sowing date and, after 100 days, roots were harvested and yield components evaluated. We evaluated the three possible analyses in lattice: 1) as randomized block design; 2) intrablock analysis with adjusted... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Daucus carota; Experimental design; Incomplete block. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000200217 |
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| Papp,Lajos Attila; Gyéresi,Árpád; Hancu,Gabriel; Mircia,Eleonora; Kelemen,Hajnal. |
| A generic capillary zone electrophoresis method was developed for the analysis of four proton pump inhibitors: omeprazole, pantoprazole, lansoprazole and rabeprazole. During preliminary analysis screening of phosphate buffers at different pH levels was performed, in order to determine the optimum pH domain suitable for the simultaneous determination of all studied compounds. A face centered central composite design was employed for the optimization of separation conditions. The effect of buffer concentration, pH and applied voltage was studied; resolution between peaks and migration time of the last compound were considered as responses. Other factors as system temperature, injection parameters, capillary length, were held constant during the optimization... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Capillary electrophoresis; Proton-pump inhibitors; Experimental design. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502019000100534 |
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| Xavier,Marcelo Fonseca; Lopes,Toni Jefferson; Quadri,Mara Gabriela Novy; Quadri,Marintho Bastos. |
| The aim of this work was to extract anthocyanins from the red cabbage. Batch studies under several extraction conditions indicated that acetic acid in aqueous solution (10% V/V) was the best solvent, used in the proportion of 0.25 g of red cabbage mL-1. At this condition, column assays were carried out to evaluate the influence of the ionic force, pH, solvent flow rate, recirculated volume of red cabbage juice and the mass of red cabbage. Results showed that the pH, recirculation and mass of red cabbage had statistically significant effects, where the optimum operation conditions found for the process were pH 2.3, recirculation volume of the solvent 0.83 L and mass of red cabbage 50 g. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anthocyanins; Extraction; Red cabbage; Experimental design; Optimization. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000100018 |
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| Souza,Geraldo da Silva e; Gomes,Eliane Gonçalves; Santos,Sandra Aparecida; Rezende,Adalgiza Souza Carneiro de; Andrade,Débora Roque de Freitas; Nogueira,Márcia Furlan; Trigo,Pablo; Abreu,Urbano Gomes Pinto de. |
| ABSTRACT This study aimed to assess the physical performance of Pantaneiro horses with and without equine infectious anemia (EIA) under functional conditions of cattle management. The horses were subjected to a performance test and split into two groups according to a completely randomized design: animals were chosen from populations testing positive and negative for EIA. Performance was measured as a function of a data envelopment analysis (DEA) model considering four outputs and one unitary input. The output measures were the distance achieved in the performance test, hematocrit as a weighted average over the test duration, respiratory rate as weighted average over the test duration, and the level of lactic acid at the test termination. Weights for the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Covariance analysis; Data envelopment analysis; Equine infectious anaemia; Experimental design; Multivariate analysis. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100502 |
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| Carvalho,Saul Jorge Pinto de; Nicolai,Marcelo; Ferreira,Renato Rodrigues; Figueira,Antonio Vargas de Oliveira; Christoffoleti,Pedro Jacob. |
| Herbicide selectivity is an agricultural technology largely exploited in chemical strategies of weed control. The joint action of several protection mechanisms avoids phytotoxicity from herbicide treatment, maintaining the level of agronomically accepted damage to a minimum, or even totally avoiding them. The major mechanism of herbicide selectivity derives from the differential metabolism between weed and crop plant species, with weeds presenting a limited ability to perform it under agronomically recommended conditions. In this case, phytotoxicity can be interpreted as an overcoming of the maximum protection capacity offered by the mechanisms of selectivity, or when considering metabolism as the main factor, the overcoming of the inherent plant ability... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phytotoxicity; Injuries; Yield; Experimental design; Crop management. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000100020 |
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| Corrêa,Juliana Moço; Christi,Divair; Torre,Carla Lieko Della; Henn,Caroline; Conceição-Silva,José Luis da; Kadowaki,Marina Kimiko; Simão,Rita de Cássia Garcia. |
| ABSTRACT A new strain of Thermomyces lanuginosus was isolated from the Atlantic Forest biome, and its β-xylosidases optimization in response to agro-industrial residues was performed. Using statistical approach as a strategy for optimization, the induction of β-xylosidases activity was evaluated in residual corn straw, and improved so that the optimum condition achieved high β-xylosidases activities 1003 U/mL. According our known, this study is the first to show so high levels of β-xylosidases activities induction. In addition, the application of an experimental design with this microorganism to induce β-xylosidases has not been reported until the present work. The optimal conditions for the crude enzyme extract were pH 5.5 and 60 °C showing better... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Experimental design; Saccharification; Β-Xylosidase; Thermomyces lanuginosus; Atlantic Forest. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822016000300680 |
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| Matei,Gilvani; Benin,Giovani; Storck,Lindolfo; Milioli,Anderson Simionato; Bozi,Antonio Henrique; Dalló,Samuel Cristian; Lucion,Ricardo Antonio. |
| ABSTRACT: The aim of this study was to evaluate the experimental precision of different methods of statistical analysis for trials with large numbers of soybean genotypes, and their relationship with the number of replicates. Soybean yield data (nine trials; 324 genotypes; 46 cultivars; 278 lines; agricultural harvest of 2014/15) were used. Two of these trials were performed at the same location, side by side, forming a trial with six replicates. Each trial was analyzed by the randomized complete block, triple lattice design, and use of the Papadakis method. The selective accuracy, least significant difference, and Fasoulas differentiation index were estimated, and model assumptions were tested. The resampling method was used to study the influence of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Resampling; Experimental precision; Experimental design; Selective accuracy. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017000400202 |
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| Registros recuperados: 46 | |
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