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Abstract Introduction The Internet Gaming Disorder Scale – Short Form (IGDS9-SF) assesses the severity, harmful effects and/or consequences of excessive online and offline gaming. Its conciseness and theoretical foundations on current diagnostic criteria of gaming disorders make it a useful resource for clinical and screening settings. Objective To describe the process of cross-cultural adaptation of the IGDS9-SF to the Brazilian context. Methods The cross-cultural adaptation involved the steps of independent translation of the instrument, synthesis version, back-translation, pre-test and elaboration of the final version. Content validity assessment was conducted by a multidisciplinary committee of experts and consisted of both a quantitative analysis (calculation of content validity coefficients – CVC) and a qualitative analysis (assessment of the experts’ comments and suggestions). The pre-test sample consisted of 30 gamers with variable sociodemographic characteristics. Results The cross-cultural adaptation of the scale followed the proposed protocol, and the CVC was satisfactory (≥ 0.83) for all the structures and equivalences assessed. Most of the suggestions made by the experts were accepted (mainly adjustments and language standardization). The gamers who participated in the pre-test judged the scale easy to understand and did not suggest changes. Discussion The Brazilian version of the IGDS9-SF showed adequate content validity and is available for researchers and clinicians, as well as for the investigation of additional psychometric characteristics.

https://doi.org/10.1590/2237-6089-2019-0032 505 downloads

Study of the effect of solvent on acetylate cashew gum-based nanoparticles properties and antimicrobial activity
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Macedo, Karolina Carneiro Morais

; Chaves, Luíse Lopes

; Vieira, Alexandre Couto Carneiro

; Nadvorny, Daniela

; Paula, Regina Célia Monteiro de

; Silva, Durcilene Alves

; Veiga, Francisco

; Ribeiro, António José

; Silva-Filho, Edson Cavalcanti

Matéria (Rio de Janeiro)

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2020, Volume 25 N. 4 elocation e-12848

Abstract: En | Text: En | PDF: En

ABSTRACT The aim of this work was to investigate the influence of acetone and dimethyl sulfoxide (DMSO) on acetylated cashew gun (aCG) nanoparticles parameters and to assess their antimicrobial activity. C1 nanoparticles presented smaller size (81.3 nm) than compared to C2 (115.7 nm). Although, acetone formed particles with lower PDI value. Both C1 and C2 presented negative zeta potential (-39.8 and -31.7 respectively). Particle tracking analysis showed that C1 was slightly more concentrated than C2. No statistical differences (p < 0.05) between the same samples after 5 months were found. Both samples did not exert inhibitory effect on E. coli, on the contrary S. aureus, in which both C1 (36.9%) and C2 (19.9%) provided important inhibitory effect. C1 presented a more pronounced antifungal effect (81.2%), compared to C2 (18.8%), indicating a promising platform to be used in several biomedical application.

https://doi.org/10.1590/s1517-707620200004.1148 408 downloads

Mating system analysis of Açaí-do-Amazonas (Euterpe precatoria Mart.) using molecular markers
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Ramos, Santiago Linorio Ferreyra

; Lopes, Maria Teresa Gomes

; Lopes, Ricardo

; Dequigiovanni, Gabriel

; Macêdo, Jeferson Luis Vasconcelos de

; Sebbenn, Alexandre Magno

; Silva, Edson Barcelos da

; Garcia, José Nivaldo

Crop Breeding and Applied Biotechnology

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jan 2019, Volume 19 N. 1 Pages 126 - 130

Abstract: En | Text: En | PDF: En

Abstract Euterpe precatoria (Açaí-do-Amazonas) produces fruits of which the fresh pulp is consumed. It is almost exclusively collected by extractivist farmers, because no selected genotypes are available for the establishment of plantations. For the domestication and breeding of the species, mating system studies are needed for strategy formulation. This study evaluated the mating system of a natural population of E. precatoria. Thirteen progenies were genotyped with 13 microsatellite loci by capillary electrophoresis in an automated DNA sequencer. Estimates of single-locus and multilocus outcrossing rates were 1.0, and paternity correlation was low ( r ^ p ( m )>= 0.293). Euterpe precatoria families consist mainly of half-sibs and the reproductive strategy of the species is allogamy.

https://doi.org/10.1590/1984-70332019v19n1n17 1262 downloads

Identification of Anti-Inflammatory and Anti-Hypertensive Drugs as Inhibitors of Bacterial Diguanylate Cyclases
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Wiggers, Helton J.

; Crusca, Edson

; Silva, Éverton E. D.

; Cheleski, Juliana

; Torres, Naiara U.

; Navarro, Marcos V. A. S.

Journal of the Brazilian Chemical Society

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feb 2018, Volume 29 N. 2 Pages 297 - 309

Abstract: En | Text: En | PDF: En

Biofilms are widely present in many human chronic infections, often more resistant to treatment with antibiotics. Bacterial diguanylate cyclases (DGCs) synthesize cyclic dimeric guanosine monophosphate (c-di-GMP) from two guanosine-5'-triphosphate (GTP) molecules. c-di-GMP is a central second messenger controlling biofilm formation, turning this class of enzymes an attractive target to prevent and disrupt biofilms of pathogenic bacteria. Here, we apply an in silico ligand- and target-based hybrid method to screen potential DGC inhibitors from an FDA-approved drug databank. Mass spectrometry assays confirmed that seven screened compounds selectively bound to the GTP active site of P. aeruginosa WspR GGDEF domain. Four out of those, including the anti-inflammatory sulfasalazine and the anti-hypertensive eprosartan, inhibited distinct DGCs (P. aeruginosa WspR and E. coli YdeH) in the micromolar range. Sulfasalazine and eprosartan reduced aggregation in solution of E. coli overexpressing WspR or YdeH. Similar anti-aggregation effects were also observed for sulfasalazine-related anti-inflammatory drugs sulfadiazine and sulfathiazole, the latter a previously described anti-biofilm agent. The optimized pharmacokinetic properties and toxicological profiles of the DGC inhibitors could be promising candidates for new anti-microbial agents based on the drug reposition strategy.

https://doi.org/10.21577/0103-5053.20170141 1091 downloads

End Functionalization by Ring Opening Polymerization: Influence of Reaction Conditions on the Synthesis of End Functionalized Poly(lactic Acid)
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Icart, Luis P.

; Fernandes, Edson

; Agüero, Lissette

; Cuesta, Maelia Z.

; Silva, Dionisio Z.

; Rodríguez-Fernández, Daniel E.

; Souza Jr., Fernando G.

; Lima, Luis Maurício T. R.

; Dias, Marcos L.

Journal of the Brazilian Chemical Society

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jan 2018, Volume 29 N. 1 Pages 99 - 108

Abstract: En | Text: En | PDF: En

In this paper, chemical functionalization of poly(lactic acid) (PLA) was carried out by using of salicyl aldehyde (SAl) and salicylic acid (SAc) as co-initiators of ring opening polymerization (ROP). Two factorial designs (22) were performed to evaluate the effects of the lactide/catalyst and co-initiator/catalyst molar ratios on the content of aldehyde or carboxylic acid end groups, thermal properties and molecular weight (Mw) of PLA. Tin(II) 2-ethylhexanoate was used as a catalyst. The co-initiator/catalyst molar ratio has a statistically significant influence on the polymer functionalization. The highest co-initiator/catalyst molar ratio of 12/1 allows the best aldehyde or carboxylic acid functionalization, independent on the lactide/catalyst molar ratio. On the other hand, the used lactide/catalyst and co-initiator/catalyst molar ratios did not show a statistically significant influence on the polymer thermal properties. Besides, co-initiator/catalyst molar ratio has a statistically significant influence on the polymer molecular weight. So, the highest co-initiator/catalyst molar ratio used (12/1) in combination with the highest lactide/catalyst ratio (125/1) produced functionalized PLA with higher molecular weights.

https://doi.org/10.21577/0103-5053.20170118 1520 downloads

Plasmid-mediated mcr-1 in carbapenem-susceptible Escherichia coli ST156 causing a blood infection: an unnoticeable spread of colistin resistance in Brazil?
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Rossi, Flavia

; Girardello, Raquel

; Morais, Carlos

; Cury, Ana Paula

; Martins, Layla Farage

; da Silva, Aline Maria

; Abdala, Edson

; Setubal, João Carlos

; da Silva Duarte, Alberto José

Clinics

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oct 2017, Volume 72 N. 10 Pages 642 - 644

Abstract: En | Text: En | PDF: En

OBJECTIVE: We describe an IncX4 pHC891/16mcr plasmid carrying mcr-1 in a colistin-resistant and carbapenem-susceptible E. coli isolate (HC891/16), ST156, which caused a blood infection in a Brazilian patient with gallbladder adenocarcinoma. METHODS: Strain HC891/16 was subjected to whole genome sequencing using the MiSeq Platform (Illumina, Inc., USA). Assembly was performed using Mira and ABACAS. RESULTS: The isolates showed resistance only to ciprofloxacin, ampicillin and cefoxitin, and whole-genome sequencing revealed the presence of aac(6’)Ib-cr and blaTEM1. CONCLUSION: Our findings warn of the possible silent dissemination of colistin resistance by carbapenem-susceptible mcr-1 producers, as colistin susceptibility is commonly tested only among carbapenem-resistant isolates.

https://doi.org/10.6061/clinics/2017(10)09 1031 downloads

Botanical secondary metabolites as alternatives for pest management in Cuba
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Pino, Oriela

; Sánchez, Yaíma

; Rojas, Miriam M.

; Jorge, Fanny

; Buzzi, Ana

; González, Cecil

; Turtos, Daylen

; Acosta, Nerdys

; Rodríguez, Mayra

; Hernández, Dainé

; Regalado, Roberto E.

; López, Lidia

; Corzo, Mylene

; Yglesia, Aleika

; Martínez, María A.

; Baños, Heyker L

; Suris, Moraima

; Ramírez, Susana

; Sánchez, Adayakni

; Rodríguez, Héctor

; Pérez, Yanebis

; Chico, Reinaldo

; Arias, Yailen

; González, Ivonne

; Hernández, Yusely

; Martínez, Benedicto

; Duarte, Yanisisa

; Infante, Danay

; Correa, Teresa M.

; Martínez, Dayamín

; Montes de Oca, Rodney

; Berroa, Georgina

; Cotilla, Lázaro

; Peteira, Belkis

; das Graças Fernandes da Silva, Maria Fátima

; Rodrigues Filho, Edson

; Akhtar, Yasmin

; Isman, Murray B.

Revista de Protección Vegetal

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dec 2015, Volume 30 Pages 36 - 36

Abstract: En | Text: En | PDF: En

Genetic variability in progenies of Eucalyptus dunnii Maiden for resistance to Puccinia psidii
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Pinto, Cleber da Silva

; Costa, Rodolfo Manoel Lemes da

; Moraes, Cristiano Bueno de

; Pieri, Cristiane de

; Tambarussi, Evandro Vagner

; Furtado, Edson Luiz

; Mori, Edson Seizo

Crop Breeding and Applied Biotechnology

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oct 2014, Volume 14 N. 3 Pages 187 - 193

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Avaliou-se a variabilidade genética em progênies de Eucalyptus dunnii Maiden para resistência à ferrugem (Puccinia psidii). Experimentos de campo foram instalados em duas regiões edafoclimáticas.Progênies de polinização aberta foram estabelecidas em um delineamento emblocos casualizados. Em condições de campo foram avaliadas 60 e 48 progênies emdois locais, com seis repetições e oito plantas por parcela. Instalou-se tambémum experimento em ambiente controlado, com 53 progênies, em blocoscasualizados, com seis repetições e nove plantas por parcela. Foram avaliadas altura da planta e a severidade de ataque que determinam a fase mais suscetível à doença foliar. A população de E. dunnii estudada apresentou altavariabilidade genética para resistência à ferrugem, com coeficiente de variaçãogenética de 36, 07% e 70% das progênies avaliadas foram imunes a ferrugem. Istoindica alto potencial para seleção e melhoramento da espécie.

This study investigated the genetic variability in progenies of Eucalyptus dunnii Maiden for resistance against rust (Puccinia psidii). Field experiments were installed in two regions with differentsoil-climatic conditions. Open-pollinated progenies were established in arandomized complete block design. Sixty and 48 progenies were evaluated underfield conditions at two sites, respectively, with six replications and eight trees per plot. In another experiment in a controlled environment, 53 progenies were evaluated in randomized blocks with six replications and nine plants perplot. The following traits were evaluated: plant height, severity of pestattack and the most susceptible stage to the leaf disease. The genetic variability for rust resistance in the E. dunnii population under studywas high, with a genetic coefficient of variation of 36.07%; 7% of thee valuated progenies were rust-resistant. It indicates a high potential for selection and breeding of the species.

https://doi.org/10.1590/1984-70332014v14n3a28 1417 downloads

The effects of soil fumigation on the growth and mineral nutrition of weeds and crops
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Santos, Edson Aparecido dos

; Ferreira, Lino Roberto

; Costa, Mauricio Dutra

; Santos, José Barbosa dos

; Silva, Marliane de Cássia Soares da

; Aspiazu, Ignacio

Acta Scientiarum. Agronomy

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jun 2012, Volume 34 N. 2 Pages 207 - 212

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Plantas daninhas e microrganismos do solo se interagem na interface solo/raiz promovendo vantagens para o desenvolvimento e estabelecimento de ambos. Objetivou-se com este trabalho avaliar o crescimento e o acúmulo de nutrientes em oito espécies de plantas daninhas (Ageratum conyzoides L., Bidens pilosa L., Cenchrus echinatus L., Conyza bonariensis L., Echinochloa crus-galli L., Eleusine indica L., Ipomoea grandifolia L. e Lolium multiflorum L.) e nas culturas de feijão e milho, cultivadas, por 50 dias, em substrato fumigado com brometo de metila. Avaliações referentes à altura, área foliar, número de folhas, matéria seca da parte aérea e das raízes e teor relativo dos nutrientes, foram realizados aos 50 dias após emergência das plântulas. Observou-se efeito positivo da fumigação do substrato no crescimento, número de folhas, área foliar, altura de plantas e acúmulo de nutrientes nas plantas daninhas gramíneas em relação às dicotiledôneas. Conyza bonariensis foi a mais afetada pela fumigação do solo, apresentando índices de matéria seca, número de folhas, área foliar, altura e acúmulo de nutrientes em torno de 50% menores em relação às plantas crescidas em solo normal. A fumigação influenciou também o ciclo vegetativo das plantas, sendo este menor para as espécies B. pilosa, E. indica e C. echinatus. Observou-se, ainda, acúmulo de fósforo 20 e 30% menor em plantas de Bidens pilosa e Conyza bonariensis, respectivamente, quando cultivadas em solo esterilizado. As culturas de feijão e milho foram menos afetadas pela fumigação do solo em comparação às plantas daninhas.

Weeds and soil microorganisms interact with each other in the soil/root interface, promoting the development and establishment of both. The objective of this study was to evaluate the growth and nutrient accumulation in eight species of weeds (Ageratum conyzoides L., Bidens pilosa L., Cenchrus echinatus L., Conyza bonariensis L., Echinochloa crus-galli L., Eleusine indica L. Ipomoea grandifolia L. and Lolium multiflorum L.) and in bean and corn crops grown for 50 days in a substrate fumigated with methyl bromide. Assessments relating to the height, leaf area, leaf number, dry weight of shoots and roots and relative content of nutrients were carried out 50 days after seedling emergence. A positive effect of soil fumigation was observed on the growth, leaf number, leaf area, plant height and accumulation of nutrients in monocot weeds in relation to dicots. Conyza bonariensis was the most affected by soil fumigation, with levels of dry matter, leaf number, leaf area, height and accumulation of nutrients approximately 50% lower than plants grown in normal soil. Fumigation also influenced the growth cycle of the plants, which was lower for B. pilosa, E. indica and C. echinatus. We also observed a 20 and 30% lower phosphorus accumulation in Bidens pilosa and Conyza bonariensis, respectively, when grown in the sterilized soil. Overall, the bean and corn crops were less affected by soil fumigation than the weeds.

https://doi.org/10.4025/actasciagron.v34i2.12971 2640 downloads

10.

Attenuated total reflectance with Fourier transform infrared spectroscopy (ATR/FTIR) and different PLS Algorithms for simultaneous determination of clavulanic acid and amoxicillin in powder pharmaceutical formulation
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Müller, Aline L. H.

; Flores, Érico M. M.

; Müller, Edson I.

; Silva, Fabiana E. B.

; Ferrão, Marco F.

Journal of the Brazilian Chemical Society

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oct 2011, Volume 22 N. 10 Pages 1903 - 1912

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Um método para determinação simultânea de ácido clavulânico (CA) e amoxicilina (AMO) foi desenvolvido utilizando a técnica de espectroscopia no infravermelho médio com transformada de Fourier acoplada ao acessório de reflexão total atenuada (ATR/FTIR). Utilizaram-se 27 e 8 amostras para os conjuntos de calibração e previsão, respectivamente. Os modelos de calibração foram desenvolvidos utilizando os algoritmos por mínimos quadrados parciais (PLS), PLS por intervalo (iPLS), PLS por sinergismo (siPLS) e PLS por exclusão (biPLS). Os melhores modelos foram aqueles que utilizaram o algoritmo biPLS. Obtiveram-se erro padrão relativo de previsão (RSEP) de 3,8 e 5,1% para CA e AMO, respectivamente. Os resultados obtidos pela metodologia proposta foram comparados com os obtidos por cromatografia líquida de alta eficiência (HPLC) e nenhuma diferença significativa foi observada. O método proposto utilizando ATR/FTIR associado a métodos de análise multivariados foi satisfatório para determinação de CA e AMO em produtos farmacêuticos.

A method for simultaneous determination of clavulanic acid (CA) and amoxicillin (AMO) was developed using Fourier transform mid infrared technique coupled with attenuated total reflectance (ATR/FTIR) accessory. 27 samples were used as calibration set and 8 samples were used for prediction set. Calibration models were developed using partial least squares (PLS), interval PLS (iPLS), synergy PLS (siPLS) and backward PLS (biPLS). Multiplicative scatter correction and the mean centering were used and produced the best models. Relative standard error of prediction (RSEP) of 3.8% for CA and 5.1% for AMO were obtained using biPLS algorithm for ATR/FTIR data. Results obtained by the proposed methodology were compared with those using high performance liquid chromatography (HPLC) and no significant differences were obtained. The proposed method using ATR/FTIR combined to multivariate analysis methods was suitable for the simultaneous determination of CA and AMO in commercial pharmaceutical products.

5591 downloads

11.

Tolerância ao déficit hídrico em genótipos de feijão-caupi
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Nascimento, Sebastião P. do

; Bastos, Edson A.

; Araújo, Eugênio C. E.

; Freire Filho, Francisco R.

; Silva, Everaldo M. da

Revista Brasileira de Engenharia Agrícola e Ambiental

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aug 2011, Volume 15 N. 8 Pages 853 - 860

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

Objetivou-se, neste trabalho, avaliar o efeito do déficit hídrico sobre as características fisiológicas e produtivas do feijão-caupi e selecionar genótipos tolerantes à seca. Avaliaram-se a condutância estomática, o potencial hídrico foliar, a temperatura das folhas e a produtividade de grãos de 20 genótipos de feijão-caupi nas condições de solo e clima de Teresina, Piauí, no ano de 2008 e se conduziram dois experimentos em delineamento de blocos ao acaso com 20 tratamentos e quatro repetições, um sob déficit hídrico durante a fase reprodutiva e outro sob irrigação plena, para fins de comparação. O déficit hídrico, que foi obtido aplicando-se aproximadamente metade da lâmina requerida pelo feijão-caupi, reduziu em 72% a condutância estomática, 62% o potencial de água nas folhas, 60% a produção de grãos e aumentou em 11,7% a temperatura foliar. Nas condições de déficit hídrico treze genótipos produziram acima da média (466 kg ha-1), com destaque para o BRS-Paraguaçu, Pingo-de-ouro-1-2 e Pingo-de-ouro-2, que produziram 712 kg ha-1, 667 kg ha-1 e 642 kg ha-1, respectivamente. Em média, a produtividade de grãos dos genótipos sob irrigação plena foi 150% superior.

The objective of this study was to evaluate physiological and productive characteristics of cowpea under water deficit and total irrigation, under soil and climate conditions of Teresina, Piauí State, in 2008. The stomatal conductance, leaf water potential, leaf temperature and grain yield of twenty cowpea cultivars were evaluated. Two experiments were carried out in a randomized block design with 20 treatments and four replications, one under water deficit during the reproductive phase and another one under total irrigation. The water deficit was obtained applying half of the water depth required by cowpea. The water deficit reduced 72% of the stomatal conductance, 40% the leaf transpiration, 62% of the leaf water potential, 60% of the grain yield and increased 11.7% the leaf temperature. Under water deficit, 13 genotypes produced above average (466 kg ha-1), and BRS-Paraguaçu, Pingo-de-ouro-1-2 and Pingo-de-ouro-2 presented the best grain yield with712 kg ha-1, 667 kg ha-1 and 642 kg ha-1, respectively. The average grain yield of the experiment under total irrigation was 150% higher.

12948 downloads

12.

Spatio-temporal modelling of the duration of the cotton cycle in the State Of Goiás, Brazil
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Antonini, Jorge C. dos A.

; Silva, Euzebio M. da

; Griebeler, Nori P.

; Sano, Edson E.

Engenharia Agrícola

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2011, Volume 31 N. 4 Pages 652 - 662

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

O objetivo deste trabalho foi desenvolver e validar um modelo matemático para estimar a duração do ciclo do algodoeiro (Gossypium hirsutum L. r. latifolium hutch) no Estado de Goiás, aplicando o método de graus-dia (GD) e considerando sua variação espaçotemporal. O modelo foi desenvolvido por meio de combinação linear entre altitude, latitude, longitude e a variação temporal, representada pela série trigonométrica incompleta de Fourier. Os parâmetros do modelo foram ajustados, por meio de regressão linear múltipla, aos dados de GD para o algodoeiro, acumulados entre 15°C e 40°C. Os dados utilizados de temperaturas máxima e mínima foram obtidos de séries históricas de 21 estações meteorológicas, com períodos de observações variando entre 8 e 24 anos. A validação do modelo foi feita comparando-se a duração da fase entre a emergência e 90% de capulhos abertos de cultivares de algodoeiros plantados em lavouras comerciais. O coeficiente de determinação resultante do ajuste do modelo aos dados observados foi de 0,84. Os resultados dessa comparação mostraram que o modelo proposto teve um desempenho muito bom, conforme indicado pelo coeficiente de correlação de Pearson de 0,90 e o índice de concordância de Willmott de 0,94, que resultaram em um índice de desempenho de 0,85.

The objective of this work was to develop and validate a mathematical model to estimate the duration of cotton (Gossypium hirsutum L. r. latifolium hutch) cycle in the State of Goiás, Brazil, by applying the method of growing degree-days (GD), and considering, simultaneously, its time-space variation. The model was developed as a linear combination of elevation, latitude, longitude, and Fourier series of time variation. The model parameters were adjusted by using multiple-linear regression to the observed GD accumulated with air temperature in the range of 15°C to 40°C. The minimum and maximum temperature records used to calculate the GD were obtained from 21 meteorological stations, considering data varying from 8 to 20 years of observation. The coefficient of determination, resulting from the comparison between the estimated and calculated GD along the year was 0.84. Model validation was done by comparing estimated and measured crop cycle in the period from cotton germination to the stage when 90 percent of bolls were opened in commercial crop fields. Comparative results showed that the model performed very well, as indicated by the Pearson correlation coefficient of 0.90 and Willmott agreement index of 0.94, resulting in a performance index of 0.85.

1605 downloads

13.

Comparing stochastic optimization methods to solve the medium-term operation planning problem
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Gonçalves, Raphael E. C.

; Finardi, Erlon C.

; Silva, Edson L. da

; Santos, Marcelo L. L. dos

Computational & Applied Mathematics

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2011, Volume 30 N. 2 Pages 289 - 313

Abstract: En | Text: En | PDF: En

The Medium-Term Operation Planning (MTOP) of hydrothermal systems aims to define the generation for each power plant, minimizing the expected operating cost over the planning horizon. Mathematically, this task can be characterized as a linear, stochastic, large-scale problem which requires the application of suitable optimization tools. To solve this problem, this paper proposes to use the Nested Decomposition, frequently used to solve similar problems (as in Brazilian case), and Progressive Hedging, an alternative method, which has interesting features that make it promising to address this problem. To make a comparative analysis between these two methods with respect to the quality of the solution and the computational burden, a benchmark is established, which is obtained by solving a single Linear Programming problem (the Deterministic Equivalent Problem). An application considering a hydrothermal system is carried out.

3695 downloads

14.

Qualidade de águas subterrâneas captadas em fontes em função da presença de proteção física e de sua posição na paisagem
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Rheinheimer, Danilo dos S.

; Gonçalves, Celso S.

; Bortoluzzi, Edson C.

; Pellegrini, João B. R.

; Silva, José L. S. da

; Petry, Cláudia

Engenharia Agrícola

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oct 2010, Volume 30 N. 5 Pages 948 - 957

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

No meio rural, a água de consumo humano é frequentemente captada por meio de sistemas precários. O objetivo do trabalho foi o de monitorar parâmetros físicos, químicos e microbiológicos da qualidade de água subterrânea captada em fontes para uso doméstico, relacionando suas posições na paisagem e à presença de proteção física. Trinta e cinco fontes de água subterrânea, localizadas na pequena bacia hidrográfica-PBH do Arroio Lino, área rural do Município de Agudo - RS, foram amostradas e classificadas quanto à proteção física e à posição na paisagem. Monitoraram-se, de janeiro a agosto de 2002, os seguintes parâmetros da água: pH, cor, carbono orgânico solúvel total (COST), N-NO3, N-NH3 e fósforo total (PT), Escherichia coli e coliformes totais. Em geral, os parâmetros variaram com a época de coleta, ficando ora acima, ora abaixo dos Valores Máximos Permissíveis previstos pelo Ministério da Saúde do Brasil. A posição das fontes nas cotas mais altas da paisagem da PBH mostrou-se determinante unicamente para a cor e o PT. A proteção rudimentar mostrou-se eficaz para o PT nas fontes posicionadas em cotas altas, no entanto apresentou respostas discrepantes na parte baixa da paisagem, considerando-se os parâmetros COST e N-NO3. A fonte drenada coletiva, sistema recomendado pela assistência técnica oficial, mostrou-se a mais eficaz em evitar a contaminação por Escherichia coli, restringindo também coliformes totais, fósforo total e N-NO3 em relação à fonte individual. A posição das fontes na paisagem e a presença de proteção física rudimentar podem ser utilizadas como critério parcial ao uso de fontes para captação de água.

In rural areas, water for human consumption is often captured by insecure systems. The objective of this work was monitoring some parameters of the quality of groundwater taken from sources, pointing out their position in the landscape and the presence of physical protection. For this , 36 sources in the watershed of Arroio Lino, a rural area of Agudo, RS, Brazil, were sampled and classified according their physical protection and position in the landscape. A monitoring program, from January to August 2002, was carried out to analyze the following parameters: pH, color, total soluble organic carbon - TSOC, N-NO3, N-NH3 and total phosphorus, E. coli and total coliforms. The parameters values changed with the time of collection and were often above the Maximum Allowable values provided by the Brazilian Ministry of Health. A rudimentary protection was efficient to the PT of the sources located in high levels; however it has present discrepant results for the low part of the landscape, considering the parameters TSOC e N-NO3. The collective drained source, system recommended by the official technical assistance, was the most efficient to avoid contamination by Escherichia coli, restricting also the levels of total coliforms, total phosphorus and N-NO3 as compared to the individual sources. The sources position in the landscape and the presence of a rudimentary physical protection can be employed as a partial criterion to accept that a water source be used for collecting water.

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15.

Sequential cloud point extraction of trace elements from biological samples and determination by inductively coupled plasma mass spectrometry
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- SciELO Analytics

Giné, Maria Fernanda

; Patreze, Aparecida F.

; Silva, Edson L.

; Sarkis, Jorge E. S.

; Kakazu, Maurício H.

Journal of the Brazilian Chemical Society

Journal Metrics
- Sobre o periódico
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2008, Volume 19 N. 3 Pages 471 - 477

Abstract: Pt En | Text: Pt En | PDF: Pt | PDF: En

A extração no ponto nuvem (CPE) foi realizada em duas etapas seqüenciais para a determinação de elementos traço em soro humano, sangue animal e dieta alimentar por espectrometria de massas com fonte de plasma indutivamente acoplado. A primeira CPE foi realizada adicionando dietil-ditiofosfato, Triton® X-114 seguida de aquecimento a 40 ºC, centrifugação e esfriamento a 0 ºC. A fase rica em surfactante foi separada para determinar Cd, Pb e Cu pela técnica de quantificação por diluição isotópica. As medidas das razões isotópicas foram caracterizadas por RSD < 0.7%. O pH da solução empobrecida em surfactantante foi ajustado entre 4 e 5 antes da adição de 4-(2-pirilidazo)resorcinol, Triton® X-114 e seguiram-se os procedimentos para atingir o ponto nuvem. Na segunda fase rica em surfactante extraída foram quantificados Co e Ni pelo método de adições de padrão com RSD < 2%. Recuperações entre 85 a 96% foram obtidas para todos os elementos. A exatidão foi aferida pela análise de materiais de referência com valores recomendados e certificados.

A two-step sequential cloud point extraction (CPE) of trace elements from small sample volumes of human serum, animal blood, and food diet is proposed to gain analytical information in the analysis by inductively coupled plasma mass spectrometry. The first CPE was attained by adding O,O-diethyldithiophosphate, the non ionic surfactant Triton® X-114 followed by heating at 40 ºC, centrifugation and cooling at 0 ºC. The resulting surfactant-rich phase was separated to determine Cd, Pb and Cu by isotope dilution. Isotope ratio measurements presented RSD < 0.7%. The residual surfactant-poor phase solution had the pH adjusted in the range 4 to 5 before the chelating reagent, 4-(2-pyridylazo) resorcinol plus surfactant Triton® X-114 were added followed by the sequence to attain the CPE. Co and Ni were quantified in the second extracted surfactant-rich phases by standard additions method with RSD < 2%. Recoveries from 85 to 96% were obtained for all elements. Analyzing reference materials with certified and recommended values assessed accuracy.

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