Optimal subdivision of land in agrarian reform projects: an analysis using genetic algorithms

J.A. Ferreira Neto, E.C. Santos Junior, U. Fra Paleo, D. Miranda Barros, and M.C.O. Moreira. 2011. Optimal subdivision of land in agrarian reform projects: an analysis using genetic algorithms. Cien. Inv. Agr. 38(2): 169-178. The objective of this manuscript is to develop a new procedure to achieve optimal land subdivision using genetic algorithms (GA). The genetic algorithm was tested in the rural settlement of Veredas, located in Minas Gerais, Brazil. This implementation was based on the land aptitude and its productivity index. The sequence of tests in the study was carried out in two areas with eight different agricultural aptitude classes, including one area of 391.88 ha subdivided into 12 lots and another of 404.1763 ha subdivided into 14 lots. The effectiveness of the method was measured using the shunting line standard value of a parceled area lot`s productivity index. To evaluate each parameter, a sequence of 15 calculations was performed to record the best individual fitness average (MMI) found for each parameter variation. The best parameter combination found in testing and used to generate the new parceling with the GA was the following: 320 as the generation number, a population of 40 individuals, 0.8 mutation tax, and a 0.3 renewal tax. The solution generated rather homogeneous lots in terms of productive capacity.

Statistical analysis of the Doppler broadening coincidence spectrum of electron-positron annihilation radiation in silicon

We report a statistical analysis of Doppler broadening coincidence data of electron-positron annihilation radiation in silicon using a (22)Na source. The Doppler broadening coincidence spectrum was fit using a model function that included positron annihilation at rest with 1s, 2s, 2p, and valence band electrons. In-flight positron annihilation was also fit. The response functions of the detectors accounted for backscattering, combinations of Compton effects, pileup, ballistic deficit, and pulse-shaping problems. The procedure allows the quantitative determination of positron annihilation with core and valence electron intensities as well as their standard deviations directly from the experimental spectrum. The results obtained for the core and valence band electron annihilation intensities were 2.56(9)% and 97.44(9)%, respectively. These intensities are consistent with published experimental data treated by conventional analysis methods. This new procedure has the advantage of allowing one to distinguish additional effects from those associated with the detection system response function. (C) 2009 Elsevier B.V. All rights reserved.

Detection of microwaves using the organic semiconductor poly(p-phenylenevinylene)

We report a new procedure to convert the polymer precursor poly(xylylidene tetrahydrothiophenium chloride) (PTHT) into poly(p-phenylenevinylene) (PPV) using microwave irradiation. Spin-coated PTHT films were irradiated at room temperature under ambient conditions in a commercial microwave oven, with varying power from 20W to 100W. Complete conversion was reached within only 5 min of irradiation for powers above 50W, yielding PPV films with absorption and photoluminescence spectra that are practically indistinguishable from the spectra of thermally converted PPV films, which require ca. 2 h of a high temperature (similar to 200 degrees C) thermal treatment. In addition to a much faster conversion procedure, the irradiation with microwaves led to a red shift in the absorption spectrum of a PTHT film, which varied linearly with the time of irradiation. These films can then be used as low-cost, easy-to-use detectors of microwaves. (C) 2010 Elsevier B.V. All rights reserved.

Ca(2+)-mediated thiolysis of peptide-resin linkage as an option for preparing protected peptide thioesters

A mild new procedure for preparing protected peptide thioesters, based oil Ca(2+)-assisted thiolysis of peptide-Kaiser oxime resin (KOR) linkage, is described. Ac-Ile-Ser(Bzl)-Asp(OcHx)-SR (Ac: acetyl; Bzl: benzyl; cHx: cyclohexyl), model peptide, was readily released from the resin by incubating the peptide-KOR at 60 degrees C in mixtures of DMF with n-butanethiol [R = (CH(2))(3)CH(3)] or ethyl 3-mercaptopropionate [R = (CH(2))(2)COOCHCH(3)] containing Ca(CH(3)COO)(2). After serine and aspartic acid side-chain deprotection under acid conditions, Ac-Ile-Ser-Asp-S(CH(2))(2)COOCH(2)CH(3) was successfully obtained with good quality and high yield. This type of C-terminal modified peptide may act as an excellent acyl donor in peptide segment condensation by the thioester method, native chemical ligation and enzymatic methods. (c) 2008 Elsevier Ltd. All rights reserved.

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.

Integração de dados em ambiente SIG para mapeamento de favorabilidade mineral de ouro na ilha cristalina de Rivera (Uruguai)

Guias para exploração mineral são normalmente baseados em modelos conceituais de depósitos. Esses guias são, normalmente, baseados na experiência dos geólogos, em dados descritivos e em dados genéticos. Modelamentos numéricos, probabilísticos e não probabilísticos, para estimar a ocorrência de depósitos minerais é um novo procedimento que vem a cada dia aumentando sua utilização e aceitação pela comunidade geológica. Essa tese utiliza recentes metodologias para a geração de mapas de favorablidade mineral. A denominada Ilha Cristalina de Rivera, uma janela erosional da Bacia do Paraná, situada na porção norte do Uruguai, foi escolhida como estudo de caso para a aplicação das metodologias. A construção dos mapas de favorabilidade mineral foi feita com base nos seguintes tipos de dados, informações e resultados de prospecção: 1) imagens orbitais; 2) prospecção geoquimica; 3) prospecção aerogeofísica; 4) mapeamento geo-estrutural e 5) altimetria. Essas informacões foram selecionadas e processadas com base em um modelo de depósito mineral (modelo conceitual), desenvolvido com base na Mina de Ouro San Gregorio. O modelo conceitual (modelo San Gregorio), incluiu características descritivas e genéticas da Mina San Gregorio, a qual abrange os elementos característicos significativos das demais ocorrências minerais conhecidas na Ilha Cristalina de Rivera. A geração dos mapas de favorabilidade mineral envolveu a construção de um banco de dados, o processamento dos dados, e a integração dos dados. As etapas de construção e processamento dos dados, compreenderam a coleta, a seleção e o tratamento dos dados de maneira a constituírem os denominados Planos de Informação. Esses Planos de Informação foram gerados e processados organizadamente em agrupamentos, de modo a constituírem os Fatores de Integração para o mapeamento de favorabilidade mineral na Ilha Cristalina de Rivera. Os dados foram integrados por meio da utilização de duas diferentes metodologias: 1) Pesos de Evidência (dirigida pelos dados) e 2) Lógica Difusa (dirigida pelo conhecimento). Os mapas de favorabilidade mineral resultantes da implementação das duas metodologias de integração foram primeiramente analisados e interpretados de maneira individual. Após foi feita uma análise comparativa entre os resultados. As duas metodologias xxiv obtiveram sucesso em identificar, como áreas de alta favorabilidade, as áreas mineralizadas conhecidas, além de outras áreas ainda não trabalhadas. Os mapas de favorabilidade mineral resultantes das duas metodologias mostraram-se coincidentes em relação as áreas de mais alta favorabilidade. A metodologia Pesos de Evidência apresentou o mapa de favorabilidade mineral mais conservador em termos de extensão areal, porém mais otimista em termos de valores de favorabilidade em comparação aos mapas de favorabilidade mineral resultantes da implementação da metodologia Lógica Difusa. Novos alvos para exploração mineral foram identificados e deverão ser objeto de investigação em detalhe.

Model selection, estimation and forecasting in VAR models with short-run and long-run restrictions

We study the joint determination of the lag length, the dimension of the cointegrating space and the rank of the matrix of short-run parameters of a vector autoregressive (VAR) model using model selection criteria. We consider model selection criteria which have data-dependent penalties for a lack of parsimony, as well as the traditional ones. We suggest a new procedure which is a hybrid of traditional criteria and criteria with data-dependant penalties. In order to compute the fit of each model, we propose an iterative procedure to compute the maximum likelihood estimates of parameters of a VAR model with short-run and long-run restrictions. Our Monte Carlo simulations measure the improvements in forecasting accuracy that can arise from the joint determination of lag-length and rank, relative to the commonly used procedure of selecting the lag-length only and then testing for cointegration.

Uso da cola de fibrina na anastomose nervosa : estudo comparativo experimental, em ratos

A procura de um método que permita um melhor resultado na anastomose de um nervo completamente seccionado é antiga. Há muitos anos a técnica, dita convencional, para aproximação dos cotos afastados do nervo lesado, é realizada com pontos de fios microcirúrgicos. Mais recentemente, a utilização da cola de fibrina tem permitido a adesão de tecidos, como pele, fáscia e outras estruturas anatômicas. O uso da cola de fibrina, na aproximação das extremidades nervosas, tem sido propagada pela indústria como um fato incontestável. No entanto, somente com a realização de estudos comparativos clínicos e laboratoriais tornou-se possível comparar a eficácia da cola de fibrina como agente de reconstituição em lesões de nervos periféricos. Com o objetivo de comprovar essa afirmação foi realizado um trabalho através de uma mensuração nas bainhas de mielina de cotos regenerados de nervos entre diferentes tipos de anastomose nervosas em nervo isquiático de ratos da raça Wistar. Com esse mesmo escopo, foi mensurado o número de axônios em regeneração após o uso dessa cola. Foi utilizada uma amostra de 35 ratos divididos em 03 grupos (A, B e C). No grupo A, 25 ratos foram submetidos à cirurgia com o uso da cola de fibrina para a anastomose nervosa. No grupo B, 05 ratos foram submetidos ao mesmo procedimento; entretanto, ao reparo nervoso acrescentou-se a utilização de dois pontos opostos de mononylon 9-0, usando-se cola de fibrina no seu interior. No terceiro grupo (C), 05 ratos foram submetidos a neurorrafia com 6 a 8 pontos de mononylon 9-0 sem auxílio da cola de fibrina (anastomose nervosa convencional). Os animais foram submetidos a um novo procedimento após 90 dias, quando o nervo isquiático tratado foi retirado e encaminhado para o estudo. Após esse procedimento, os animais foram sacrificados. Cabe esclarecer que os espécimens foram submetidas a uma preparação histológica, sendo avaliados. Para tanto, foi realizada uma mensuração da espessura média da bainha de mielina das fibras regeneradas. Também foi realizada uma medição do número de axônios regenerados em um milímetro quadrado. Com base nesses achados, foram comparados os resultados.

Responsabilidade tributária de grupos econômicos

A presente pesquisa tem por objetivo investigar a responsabilidade tributária de grupos econômicos. Para tanto, analisa inicialmente o que é grupo econômico a partir da evolução da organização da empresa, verificando as formas de regulação no direito societário, bem como nos demais ramos do direito, especialmente o tributário. Em seguida, se debruça sobre a limitação da responsabilidade, a desconsideração da personalidade jurídica e a responsabilidade tributária. Verifica, então, em quais hipóteses poderia haver a responsabilidade tributária de grupos econômicos, sendo analisadas as possibilidades com fundamento legal no art. 30, IX, da Lei nº 8.212/91; art. 124 da Lei nº 5.172/66; art. 50 da Lei nº 10.406/2002; art. 990 da Lei nº 10.406/02 combinado com o art. 126, III, da Lei nº 5.172/66; e art. 116, §1º, da Lei nº 5.172/66. Por fim, aborda aspectos processuais da responsabilidade de grupos econômicos, com enfoque no incidente de desconsideração da personalidade jurídica previsto no Código de Processo Civil de 2015.

Circulating leukocyte heat shock protein 70 (HSP70) and oxidative stress markers in rats after a bout of exhaustive exercise

A novel method to measure oxidative stress resulting from exhaustive exercise in rats is presented. In this new procedure we evaluated the erythrocyte antioxidant enzymes, catalase ( CAT) and glutathione reductase (GR), the plasma oxidative attack markers, reactive carbonyl derivatives (RCD) and thiobarbituric reactive substances (TBARS). Muscular tissue damage was evaluated by monitoring plasma creatine kinase (CK) and plasma taurine ( Tau) concentrations. Also, we monitored total sulphydryl groups (TSG) and uric acid (UA), and the level of the 70 kDa heat shock protein (HSP70) in leukocytes as a marker of oxidative stress. In the study we found a correspondence between erythrocyte CAT and GR activities and leukocyte HSP70 levels, principally 3 h after the acute exercise, and this suggested an integrated mechanism of antioxidant defense. The increase in levels of plasma Tau was coincident with the increasing plasma levels of CK and TBARS, principally after two hours of exercise. Thus tissue damage occurred before the expression of any anti-oxidant system markers and the monitoring of Tau, CK or TBARS may be important for the estimation of oxidative stress during exhaustive exercise. Furthermore, the integrated analyses could be of value in a clinical setting to quantify the extent of oxidative stress risk and reduce the need to perform muscle biopsies as a tool of clinical evaluation.

Análise in vitro da atividade antifúngica e de toxicidade da anfotericina B pré-aquecida

The aim of this work was to evaluate how an aqueous micellar system containing Amphotericin B (AmB) and sodium deoxycholate (DOC) can be rebuilt after heating treatment. Also a review of the literature about the new physicochemical and biological properties of this new system was carried out. Afterwards, heated (AmB-DOC-H) and unheated (AmB-DOC) micelles were subsequently diluted at four different concentrations (50mg.L-1, 5mg.L-1, 0.5mg.L-1 and 0.05mg.L-1) to perform the physicochemical study and, then, the pharmacotoxicity assay, in which two cell models were used for the in vitro experiments, Red Blood Cells (RBC) from human donors and Candida parapisilosis (Cp). While potassium (K+) and hemoglobin leakage from RBC were the used parameters to evaluate the acute and chronic toxicity, respectively, the efficacy of AmB-DOC and AmB-DOC-H were assessed by K+ leakage and cell survival rate from Cp. The spectral study revealed a slight change on the aggregate peak from 327nm to 323nm for AmB-DOC-H compared to AmB-DOC. Concerning the toxicity, although AmB-DOC and AmB-DOC-H presented different behavior for hemoglobin leakage, AmB-DOC produced higher leakage than AmB-DOC-H at high concentrations (from 5mg.L-1) with values tending to zero. However, concerning K+ leakage, both AmB-DOC and AmB-DOC-H, showed similar profile for both cell models, RBC and Cp (p<0,05). AmB-DOC-H and AmB-DOC also revealed similar profile of activity against Cp with equivalent survival rate. In short, the AmB-DOC-H showed much less toxicity than AmB-DOC, but remained as active as the late one against fungal cell. Therefore, the results highlight the importance of this new procedure as a simple, inexpensive and safe alternative to produce a new kind of micelle system for treatment of systemic fungal infections

How can micelle systems be rebuilt by a heating process?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Position-dependent effective mass Dirac equations with PT-symmetric and non-PT-symmetric potentials

We present a new procedure to construct the one-dimensional non-Hermitian imaginary potential with a real energy spectrum in the context of the position-dependent effective mass Dirac equation with the vector-coupling scheme in 1 + 1 dimensions. In the first example, we consider a case for which the mass distribution combines linear and inversely linear forms, the Dirac problem with a PT-symmetric potential is mapped into the exactly solvable Schrodinger-like equation problem with the isotonic oscillator by using the local scaling of the wavefunction. In the second example, we take a mass distribution with smooth step shape, the Dirac problem with a non-PT-symmetric imaginary potential is mapped into the exactly solvable Schrodinger-like equation problem with the Rosen-Morse potential. The real relativistic energy levels and corresponding wavefunctions for the bound states are obtained in terms of the supersymmetric quantum mechanics approach and the function analysis method.

Approach combining on-line metal exchange and tangential-flow ultrafiltration for in-situ characterization of metal species in humic hydrocolloids

This paper deals with the development and optimization of an analytical procedure using ultrafiltration and a flow-injection system, and its application in in-situ experiments to characterize the lability and availability of metal species in humic-rich hydrocolloids. The on-line system consists of a tangential flow ultrafiltration device equipped with a 3-kDa filtration membrane. The concentration of free ions in the filtrate was determined by atomic-absorption spectrometry, assuming that metals not complexed by aquatic humic substances (AHS) were separated from the complexed species (M-AHS) retained by the membrane. For optimization, exchange experiments using Cu(II) solutions and AHS solutions doped with the metal ions Ni(II), Mn(II), Fe(III), Cd (II), and Zn(II) were carried out to characterize the stability of the metal-AHS complexes. The new procedure was then applied in-situ at a tributary of the Ribeira do Iguape river (Iguape, São Paulo State, Brazil) and evaluated using the ions Fe(III) and Mn(II), which are considered to be essential constituents of aquatic systems. From the exchange between metal-natural organic matter (M-NOM) and the Cu(II) ions it was concluded that Cu(II) concentrations > 485 mu g L(-1) were necessary to obtain maximum exchange of the complexes Mn-NOM and Fe-NOM, corresponding to 100% Mn and 8% Fe. Moreover, the new analytical procedure is simple and opens up new perspectives for understanding the complexation, transport, stability, and lability of metal species in humic-rich aquatic environments.

Bone Spreading and Standardized Dilation of Horizontally Resorbed Bone: Technical Considerations

The uses of a new bone spreading technique with simultaneous implant placement are discussed. The spreading system is an alternative technique to Summers' osteotome. Specific screw designs (spreader) served to laterally compress the bone to increase the cancellous density adjacent to the site. The spreader achieved a controlled and standardized dilation of horizontal bone. The advantages, material selection, and the application of this new procedure are detailed. (Implant Dent 2009; 18:119-125)