Sensitivity of the marine benthic copepod Tisbe biminiensis (copepoda, harpacticoida) to potassium dichromate and sediment particle size

For the future use of the marine benthic copepod Tisbe biminiensis in solid-phase sediment toxicological bioassays, the present study investigated the effect of muddy sediment from the Maracaípe estuary (northeastern Brazil), sediment particle size and the reference toxicant potassium dichromate on the species. Muddy sediment from Maracaípe can be used as control sediment, since it does not interfere in the copepod life-cycle and has metal contamination levels that are unlikely to produce any detrimental biological effects on benthic invertebrates. Neither survival nor fecundity was affected by grain size, suggesting that this species can be used with any kind of sediment from muddy to sandy. The sensitivity of T. biminiensis to K2Cr2O7 in acute tests was similar to that of other organisms. The LC50 (lethal concentration to 50% of the test organisms) medium values for T. biminiensis were 7.51, 4.68 and 3.19 mg L-1 for Cr in 48, 72 and 96 h, respectively. These results suggest that T. biminiensis is a promising organism for use in solid-phase sediment toxicity assessments.Visando o uso futuro do copépodo marinho bentônico Tisbe biminiensis em bioensaios toxicológicos de sedimentos na fase sólida, o presente estudo investigou o efeito do sedimento lamoso do estuário de Maracaípe (Nordeste do Brasil). Foram considerados a granolometria e o tóxico de referência dicromato de potássio sobre a espécie. O sedimento lamoso de Maracaípe pode ser usado como controle, uma vez que não interfere no ciclo de vida do copépodo e possui níveis de contaminação de metais que não causariam efeitos biológicos em invertebrados bentônicos. Nem a sobrevivência ou fecundidade foi afetada pelo tamanho do grão, sugerindo que esta espécie pode ser usada com qualquer tipo de sedimento, de lama a areia. A sensibilidade de T. biminiensis ao K2Cr2O7 em testes agudos foi similar a de outros organismos. Os valores de CL50 (concentração letal a 50% dos organismos) para T. biminiensis foram em média 7,51, 4,68 e 3,19 mg L-1 para o Cr em 48, 72 e 96h, respectivamente. Estes resultados sugerem que T. biminiensis é um organismo promissor para uso em avaliações de toxicidade com a fase sólida do sedimento

A Monte Carlo Methodology for Environmental Assessment Applied toOffshore Processing of Natural Gas with High Carbon Dioxide Content

Offshore production of oil and natural gas with high carbon dioxide content and high gas-to-oil ratio entail stringent processing conditions that require innovations and first-of-a-kind designs, which bear uncertainties derived from the scarcity of commercial-scale projects, hindering to move along technology learning curves. Consequently, unpredicted scenarios and unachieved specifications cause economic and environmental losses. Such uncertainties force offshore plants to be designed under stochastic factors seeking best statistical performance. The Monte Carlo Method is suitable to such finality. This work proposes a computer-aided engineering framework ‘MCAnalysis’ automatically applying a probabilistic environmental assessment of offshore gas processing. ‘MCAnalysis’ integrates HYSYS simulator with ‘Waste Reduction Algorithm’ to assess potential environmental impacts, whose most relevant categories were identified via Principal Component Analysis. An offshore plant processing natural gas with high carbon dioxide content was submitted to probabilistic raw gas flow rate under two scenarios of carbon dioxide content. The higher carbon dioxide content scenario presented the highest probabilistic potential environmental impacts, being the atmospheric category the most relevant

High molecular weight polystyrene particles by cationic miniemulsion polymerization catalyzed by an iron-containing imidazolium-based ionic liquid

Cationic styrene polymerizations in aqueous media were conducted using the miniemulsion polymerization technique with the ionic liquid 1-N-butyl-3-N-methylimidazolium heptachloro diferrate (BMI.Fe2Cl7) as catalyst, hexadecyltrimethylammonium bromide (CTAB) as surfactant and hexadecane as costabilizer. The ionic liquid was effective to initiate styrene miniemulsion polymerization at a BMI.Fe2Cl7:styrene molar ratios as low as 1:1000. Increasing the reaction temperature from 70 °C to 90 °C led to an increase in both, conversion and molecular weight. And polystyrene with much higher molecular weight (viscosity average molecular weights of up to 2231 kDa) than those usually obtained in cationic polymerizations was produced. Furthermore, while particle sizes remained almost constant around 150 nm during polymerizations, an almost linear increase of conversion with reaction time was observed. In addition, molecular weight increased steadily with conversion approaching the behavior of living cationic polymerization. Please click Additional Files below to see the full abstrac

Avaliação do bacharelado em Turismo no Brasil à luz do Exame Nacional de Desempenho dos Estudantes (ENADE)

O presente artigo tem como objetivo avaliar o curso de bacharelado em Turismo no Brasil com base nos indicadores dos cursos no Exame Nacional de Desempenho dos Estudantes (Enade), no período de 2006 a 2012, bem como conhecer a visão que as Instituições de Ensino Superior (IES) e as associações/entidades profissionais da área de turismo têm a respeito do referido exame. Para construção deste trabalho foram realizadas pesquisas bibliográfica, documental e de campo, nas quais foram aplicados questionários a docentes e coordenadores de cursos, bem como a representantes de associações e entidades de classe. Foi possível observar que o Enade é um instrumento de avaliação relevante que impacta na formação do estudante, bem como na atuação de coordenadores e professores de IES, ainda que a relevância desse processo e a infinidade de possibilidades de aprimoramento educacionais apresentadas pelo referido exame não estejam totalmente claras para esses acadêmicos e profissionais

Synthesis, anti-toxoplasma gondii and antimicrobial activities of 2-hydrazolyl-3-phenyl-5-(4-nitrobenzylidene)-4-thiazolidinone substituted derivatives

A novel series of 2-hydrazolyl-3-phenyl-5-(4-nitrobenzylidene)-4-thiazolidinone substituted (3a-p) has been synthesized. The intermediates 2-hydrazolyl-3-phenyl-4-thiazolidinone substituted (2a-p) were prepared by condensation of benzaldehyde 4-phenyl-3-thiosemicarbazone substituted (1a-p) with ethyl chloroacetate. Theses intermediates were submitted to reaction with ethyl 2-cyano-3-(4-nitrophenyl)-acetate to give the title compounds. The 4-thiazolidinones were screened for their anti-Toxoplasma gondii, and all derivatives promoted decrease of percentage of infection of Vero cells, with elimination of intracellular tachyzoites. The LD50 ranged around 0.5 mM for the intracellular parasites and were higher than 10 mM for Vero cells. According to results of antimicrobial activity, only two compounds showed significant inhibition against M. luteus, but demonstrated higher values of MIC and MBC when compared with standard drug.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Avaliação sorológica, clínica e epidemiológica da toxocaríase em áreas urbanas do sul do Brasil

Toxocariasis is a worldwide public-health problem that poses major risks to children who may accidentally ingest embryonated eggs of Toxocara. The objectives of this study were to investigate the occurrence of anti-Toxocara spp. antibodies in children and adolescents and the variables that may be involved, as well as environmental contamination by Toxocara spp. eggs, in urban recreation areas of north central mesoregion, Paraná State, Brazil. From June 2005 to March 2007. a total of 376 blood samples were collected by the Public Health Service from children and adolescents one to 12 years old, of both genders. Samples were analyzed by the indirect ELISA method for detection of anti-Toxocara antibodies. Serum samples were previously absorbed with Ascaris suum antigens, and considered positive with a reagent reactivity index >;1. Soil samples from all of the public squares and schools located in the four evaluated municipalities that had sand surfaces (n = 19) or lawns (n = 15) were analyzed. Of the 376 serum samples, 194 (51.6%) were positive. The seroprevalence rate was substantially higher among children aging one to five years (p = 0.001) and six to eight years (p = 0.022). The clinical signs and symptoms investigated did not show a statistical difference between seropositive and seronegative individuals (p >; 0.05). In 76.5% of the investigated recreation places, eggs of Toxocara were detected in at least one of the five collected samples. Recreation areas from public schools were 2.8 times more contaminated than from public squares. It is important to institute educational programs to inform families and educators, as well as to improve sanitary control of animals and cleaning of the areas intended for recreation in order to prevent toxocariasis.A toxocaríase é um problema de saúde pública mundial, com maior risco para crianças que podem, acidentalmente, ingerir ovos embrionados de Toxocara spp.. Os objetivos deste estudo foram avaliar a ocorrência de anticorpos anti-Toxocara spp. em crianças e adolecentes e as variáveis que podem estar envolvidas, bem como a contaminação ambiental por ovos de Toxocara spp., em locais de recreação, em áreas urbanas da mesorregião norte central, Paraná, Brasil. De junho de 2005 a março de 2007 foram coletadas 376 amostras de sangue de crianças e adolescentes de um a doze anos, de ambos os sexos, atendidas pelo Sistema Único de Saúde. As amostras foram analisadas pelo método de ELISA indireto para detecção de IgG anti-Toxocara e previamente absorvidas com antígeno de Ascaris suum. Foram consideradas reagentes as amostras com índice de reatividade >; 1. A análise das amostras de areias (n = 19) e gramados (n = 15) de cada município foi realizada em todas as praças e escolas públicas. Das 376 amostras de soro, 194 (51,6%) foram positivas. A taxa de soroprevalência foi substancialmente mais elevada entre as crianças na faixa etária de até um a cinco (p = 0.001) e de seis a oito anos de idade (p = 0,022). Os sinais e sintomas clínicos investigados não mostraram diferenças estatísticas entre soropositivos e soronegativos (p >; 0,05). Em 76,5% dos locais de recreação investigados, ovos de Toxocara foram detectados em pelo menos uma das cinco amostras. Os locais de recreação das escolas públicas estavam 2,8 vezes mais contaminados do que as praças. É importante a realização de programas educativos junto às famílias e educadores, o controle sanitário de animais e a higienização dos locais destinados à recreação para prevenção da toxocaríase

Synthesis, anti-toxoplasma gondii and antimicrobial activities of 2-hydrazolyl-3-phenyl-5-(4-nitrobenzylidene)-4-thiazolidinone substituted derivatives

A novel series of 2-hydrazolyl-3-phenyl-5-(4-nitrobenzylidene)-4-thiazolidinone substituted (3a-p) has been synthesized. The intermediates 2-hydrazolyl-3-phenyl-4-thiazolidinone substituted (2a-p) were prepared by condensation of benzaldehyde 4-phenyl-3-thiosemicarbazone substituted (1a-p) with ethyl chloroacetate. Theses intermediates were submitted to reaction with ethyl 2-cyano-3-(4-nitrophenyl)-acetate to give the title compounds. The 4-thiazolidinones were screened for their anti-Toxoplasma gondii, and all derivatives promoted decrease of percentage of infection of Vero cells, with elimination of intracellular tachyzoites. The LD50 ranged around 0.5 mM for the intracellular parasites and were higher than 10 mM for Vero cells. According to results of antimicrobial activity, only two compounds showed significant inhibition against M. luteus, but demonstrated higher values of MIC and MBC when compared with standard drug.Colegio de Farmacéuticos de la Provincia de Buenos Aire