Metal transport parameters of a gneiss saprolitic silty soil for liner design

Diffusion coefficients and retardation factors of two metal cations (Cd2+ and Pb2+) were measured for a compacted Brazilian saprolitic soil derived from gneiss, aiming to assess its geoenvironmental performance as a liner for waste disposal sites. This soil occurs extensively all over the country in very thick layers, but has not been used in liners because of its hydraulic conductivity, higher than 10(-9) m/s when compacted at optimum water content of standard Proctor energy, but which can be reduced by means of appropriate compaction techniques or additives. Batch, column, and diffusion tests were carried out with monospecies synthetic solutions at pH 1, 3, and 5.5. Measured diffusion coefficients varied between 0.5 and 4 X 10(-10) m(2)/s. Retardation factors show that cadmium, a very mobile cation, is not adsorbed at pH I but is significantly retained at pH 3 and pH 5.5, whereas lead is retained at all tested pH values though slightly at pH 1. Estimated retardation factors from batch tests were 1.3-2.3 times those resulting from column tests and at its highest when obtained by diffusion tests; whereas batch tests allow a more complete exposure of the soil grains to the solution, time-dependent nonspecific adsorption may take longer to occur. The importance of contact time was observed and should be considered in further investigations. Its significant retention of metals suggests a promising utilization of this soil as a bottom liner for wastes landfills.

Quantification of N-acetylcysteine in pharmaceuticals using cobalt phthalocyanine modified graphite electrodes

Flow injection analysis (FIA) with amperometric detection was employed for the quantification of N-acetylcysteine (NAC) in pharmaceutical formulations, utilizing an ordinary pyrolytic graphite (OPG) electrode modified with cobalt phthalocyanine (CoPc). Cyclic voltammetry was used in preliminary studies to establish the best conditions for NAC analysis. In FIA-amperometric experiments the OPG-CoPc electrode exhibited sharp and reproducible current peaks over a wide linear working range (5.0 x 10(-5)-1.0 x 10(-3) mol L(-1)) in 0.1 mol L(-1) NaOH solution. High sensitivity (130 mA mol(-1) cm(2)) and a low detection limit (9.0 x 10(-7) mol L(-1)) were achieved using the sensor. The repeatability (R.S.D.%) for 13 successive flow injections of a solution containing 5.0 x 10(-4) mol L(-1) NAC was 1.1%. The new procedure was applied in analyses of commercial pharmaceutical products and the results were in excellent agreement with those obtained using the official titrimetric method. The proposed amperometric method is highly suitable for quality control analyses of NAC in pharmaceuticals since it is rapid, precise and requires much less work than the recommended titrimetric method. (C) 2010 Elsevier B.V. All rights reserved.

Determination of carbaryl in tomato ""in natura"" using an amperometric biosensor based on the inhibition of acetylcholinesterase activity

This work reports the utilization of two methodologies for carbaryl determination in tomatoes. The measurements were carried out using an amperometric biosensor technique based on the inhibition of acetylcholinesterase activity due to carbaryl adsorption and a HPLC procedure. The electrochemical experiments were performed in 0.1 mol L-1 phosphate buffer solutions at pH 7.4 with an incubation time of 8 min. The analytical curve obtained in pure solutions showed excellent linearity in the 5.0 x 10(-5) to 75 x 10(-5) mol L-1 range, with the limit of detection at 0.4 x 10(-3) gL(-1). The application of such a methodology in tomato samples involved solely liquidising the samples, which were spiked with 6.0 x 10(-6) and 5.0 x 10(-5) mol L-1 carbaryl. Recovery in such samples presented values of 99.0 and 92.4%, respectively. In order to obtain a comparison, HPLC experiments were also conducted under similar conditions. However, the tomato samples have to be manipulated by an extraction procedure (MSPD), which yielded much lower recovery values (78.3 and 84.8%, respectively). On the other hand, the detection limit obtained was much lower than that for the biosensor, i.e., 3.2 x 10(-6) g L-1. Finally, the biosensor methodology was employed to analyze carbaryl directly inside the tomato, without any previous manipulation. In this case, the biosensor was immersed in the tomato pulp, which had previously been spiked with the pesticide for 8 min, removed and inserted in the electrochemical cell. A recovery of 83.4% was obtained, showing very low interference of the matrix constituents. (C) 2007 Elsevier B.V. All rights reserved.

Electroanalytical Method for the Analysis of Methyldopa In Pharmaceutical Tablets Using a Crude Extract of Laccase from Pycnoporus sanguineus as Oxidizing Agent

Several colorimetric and chromatographic methods have been used for the identification and quantification of methyldopa (MA) in pharmaceutical formulations and clinical samples. However, these methods are time- and reagent-consuming, which stimulated our efforts to develop a simple, fast, and low-cost alternative method. We carried out an electroanalytical method for the determination of MA in pharmaceutical formulations using the crude enzymatic extract of laccase from Pycnoporus sanguineus as oxidizing agent. This method is based on the biochemical oxidation of MA by laccase (LAC), both in solution, followed by electrochemical reduction on glassy carbon electrode surface. This method was employed for the determination of MA in pure and pharmaceutical formulations and compared with the results obtained using the official method. A wide linear curve from 23 x 10(-5) to 1 x 10(-4) mol L(-1) was found with a detection limit calculated from 43 x 10(-6) mol L(-1).

"Selling/Buying"

The article belongs to the field of lexical semantics studies, associated with describing the Russian linguistic world-image. The work focuses on the universal situation of purchase and sale as reflected in the Russian language.

Efeito da idade sobre as principais características andrológicas de touros Brangus- Efeito da idade sobre as principais características andrológicas de touros BrangusIbagé criados extensivamente no estado do Mato Grosso do Sul - Brasil Ibagé criados extensivamente no estado do Mato Grosso do Sul - Brasil

Background: Bull fertility is extremely important for beef cattle production systems and has a multiplier impact on the economical and zootechnical indexes of the herd. Bulls raised in tropical conditions may present varied seminal characteristics due to, among other causes, different management practices and quality of pastures. Another factor that influences the semen characteristics is the age of the sire. The reproductive potential of bull evaluated through the andrological exam aims to ensure the semen quality and to improve the herd reproductive efficiency. The aim of this study was to evaluate the main semen parameters of Brangus-Ibage bulls extensively reared in eastern Mato Grosso do Sul state and to verify the effect of age on the andrological characteristics analyzed. It was also evaluated the correlation between age, scrotal circumference, and physical and morphological sperm characteristics produced by the Brangus bulls.Materials, Methods & Results: The study took place in the month of July 2010, during the routine andrological examination of 168 synthetic Brangus-Ibage bulls (5/8 Angus x 3/8 Nelore), belonging to the same property. For data analysis the animals were divided by age groups: animals younger than 4 years (Age I), animals between 4 and 8 years of age (Age II), and animals between 8 and 15 years of age (Age III). In another analysis, the animals were grouped according to the sperm motility pattern obtained from the semen collection: sperm motility lower than 40% (Motility I), sperm motility between 40 and 70% (Motility II) and sperm motility between 70 and 90% (Motility III). The results of the present study demonstrated an effect of age (P < 0.05) on the following androgical characteristics: scrotal circumference, ejaculate volume, sperm vigor, major defects, minor defects and total defects. It was also observed that the animals with higher sperm motility presented higher (P < 0.05) scrotal circumference, and lower (P < 0.05) percentages of major and total defects. Among the andrological characteristics evaluated in the present work, it was observed positive correlations between age and scrotal circumference (R =0.299; P =0.000), age and volume of ejaculate (R =0.161; P =0.037), age and major defects (R =0.188; P =0.015), sperm motility and scrotal circumference (R =0.245; P =0.001), sperm motility and sperm vigor (R =0.483; P =0.000), and between major defects and total defects (R =0.946; P =0.000). Also, negative correlations were observed between sperm motility and total defects (R =-0.372; P =0.000), sperm vigor and major defects (R =-0.498; P =0.000), and sperm vigor and total defects (R =-0.432; P =0.000).Discussion: Based on the results of this study it was concluded that the Brangus-Ibage bulls utilized for natural breeding in eastern Mato Grosso do Sul, Brazil, presented satisfactory semen quality taking into account the quality of the pastures where the animals were located. In addition, the scrotal circumference, the ejaculate volume, the sperm vigor, and the percentage of morphological characteristics were influenced by the age of the bulls. Therefore, considering the production system and the environmental conditions, the animals with age between 4 and 8 years were superior regarding the sperm parameters evaluated.

Omissão de macronutrientes no crescimento e no estado nutricional de plantas de repolho cultivado em solução nutritiva

Given the importance of heart, especially among the high brassica consumption, coupled with the scarcity of studies that report symptoms of nutritional disorders in the culture, the work was carried out to evaluate the effect of the omission of macronutrients in the development and nutritional status of cabbage, and describe visual symptoms of nutritional deficiency. The experiment was conducted under greenhouse conditions in the UNESP, Jaboticabal, SP. The experiment was arranged in completely randomized design with three replications and seven treatments, corresponding to complete nutritive solution (macro and micronutrients) and individual N, P, K, Ca, Mg and S omission. Plant height, number of leaves, leaf area, shoot, root and whole plant dry mass and macronutrient levels were determined and nutritional deficiency symptoms were described. Individual omissions of N, P, K or Ca were limiting for cabbage growth, considerably reducing plant height, number of leaves, and shoot, root and whole plant dry mass. Nutritional deficiency symptoms were observed for each element. Shoot macronutrient levels in control and nutrient omission treatments were, respectively: N = 31.0-11.9; P = 5.3-0.60; K = 63.5-4.8; Ca = 25.9-4.8; Mg = 5.2-0.5; S = 10.3-1.4 g kg(-1).

Desempenho agronômico da cultura do milho e espécies forrageiras em sistema de Integração Lavoura-Pecuária no Cerrado

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

Influência do tamanho e da forma da semente de milho sobre o desenvolvimento da planta e a produtividade de grãos

Due to the small and the round seeds represent a rather high proportion of an ear, this experiment viewed to study the effects of those factors on seed germinative performance in the field as well as on the plant traits related to grain yield. Six treatment combinations replicated five times were sown in Votuporanga/SP on 08/22/2008. Flat shaped (C) and round shaped (R) seeds were made to go through flat round and oblong hole screens which resulted in the following treatments: 1. C1: seeds remaining on the top of a 23/64 '' round hole screen, 2. C2G: 21/64 '', 3. C3M: 17/64 '' or 16/64 '', 4. R2GM: medium length seeds remaining on the top of 13 x 3/4 '' oblong hole screen, 5. R3M: medium length seeds remaining on a 12 x 3/4 '' (from 1 to 2 mm bigger than R3), and 6. R3: 12 x 3/4 ''. The soil of the experimental area was submitted to a no-till cultivation system and the rows were set 0.6 m apart from one another. Fifteen days after emergence (DAE), the plants were thinned to a population of 66,000 plants/ha. Harvest took place 115 DAE and the mean yield was of 12,498 kg ha(-1). Based on the results it was concluded that only the initial growth of the plants is significantly affected by seed size. Plant traits such as plant height, ear insertion height, culm diameter, number of grains per year, grain weight and size as well as grain yield evaluated 40 or more DAE are not significantly affected by seed size or seed shape.

Resposta da crotalária a épocas e subdoses de aplicação de glifosato

The use of glyphosate sub-lethal rates can be an alternative to reduce the plant height of sunn hemp, facilitating its mechanical harvest. However, little known on the other effects that its application can result in this culture. This work aimed to evaluate the influence of application times (10; 20 and 30 days after the emergence) and glyphosate sub-lethal rates (0; 30; 60; 90 and 120 g ha(-1)), on the vegetative and reproductive development of Crotalaria juncea cultivated in no-tillage system. The experiment was conducted between the january and june months of year 2010, in Selviria, Mato Grosso do Sul State, Brazil, on a clayey Rhodic Haplustox (20 degrees 20' S and 51 degrees 24' W). The experiment design was randomized blocks in factorial arrangement 3 x 5 (application times x glyphosate rates), with four replicates. Were measured agronomic characters and productivity and the results undergone to the test F, being the times averages compared by Tukey test (P<0.05) and of rates by regression analysis. The stem diameter, seeds number per pod and mass of one thousand seeds not were affected by glyphosate application. Despite the glyphosate have provided reduction in plant height and increase of the branches number in Crotalaria juncea, not recommended the sub-lethal rates application of product per of affect straightly the culture productivity.

Uma investigação de algoritmos exatos e metaheurísticos aplicados ao nonograma

Nonogram is a logical puzzle whose associated decision problem is NP-complete. It has applications in pattern recognition problems and data compression, among others. The puzzle consists in determining an assignment of colors to pixels distributed in a N  M matrix that satisfies line and column constraints. A Nonogram is encoded by a vector whose elements specify the number of pixels in each row and column of a figure without specifying their coordinates. This work presents exact and heuristic approaches to solve Nonograms. The depth first search was one of the chosen exact approaches because it is a typical example of brute search algorithm that is easy to implement. Another implemented exact approach was based on the Las Vegas algorithm, so that we intend to investigate whether the randomness introduce by the Las Vegas-based algorithm would be an advantage over the depth first search. The Nonogram is also transformed into a Constraint Satisfaction Problem. Three heuristics approaches are proposed: a Tabu Search and two memetic algorithms. A new function to calculate the objective function is proposed. The approaches are applied on 234 instances, the size of the instances ranging from 5 x 5 to 100 x 100 size, and including logical and random Nonograms

Regular and Platform Switching: Bone Stress Analysis Varying Implant Type

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

Quartz Crystal Microbalance monitoring the real-time binding of lectin with carbohydrate with high and low molecular mass

Quartz Crystal Microbalance (QCM) was used to monitor the mass changes on a quartz crystal surface containing immobilized lectins that interacted with carbohydrates. The strategy for lectin immobilization was developed on the basis of a multilayer system composed of Au-cystamine-glutaraldehyde-lectin. Each step of the immobilization procedure was confirmed by FTIR analysis. The system was used to study the interactions of Concanavalin A (ConA) with maltose and Jacalin with Fetuin. The real-time binding of different concentrations of carbohydrate to the immobilized lectin was monitored by means of QCM measurements and the data obtained allowed for the construction of Langmuir isotherm curves. The association constants determined for the specific interactions analyzed here were (6.4 +/- 0.2) X 10(4) M-1 for Jacalin-Fetuin and (4.5 +/- 0.1) x 10(2) M-1 for ConA-maltose. These results indicate that the QCM constitutes a suitable method for the analysis of lectin-carbohydrate interactions, even when assaying low molecular mass ligands such as disaccharides. Published by Elsevier B.V.

Eletrodo modificado com filme de poli aminoácido para determinação de hidrazina em água de caldeira

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

Determinação espectrofotométrica de citrato de sildenafil em formulações farmacêuticas

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