Development and validation of a HPLC method for the determination of aldicarb, aldicarb sulfoxide and aldicarb sulfone in liquid samples from anaerobic reactors

This study describes the development and validation of a high-performance liquid chromatography (HPLC) method for detecting aldicarb and its residues in liquid samples without pretreatment. The HPLC system was equipped with a C-18 column and the mobile phase was composed of a mixture of water and acetonitrile using a linear gradient elution. The UV detector was utilized at 210 nm. Methomyl was used as an internal standard. Water and synthetic medium were used as solvents. The method was linear from 0.49-15.0 mg L-1 (r² > 0.9985), 0.1-5.0 mg L-1 (r² > 0.9974) and 0.1-5.0 mg L-1 (r² > 0.9987) for aldicarb, aldicarb sulfoxide and aldicarb sulfone, respectively. The linearity of the method was confirmed by the ANOVA F-test through adjustment of the linear model, validity of the regression and efficiency of the regression tests. The limit of detection in water and synthetic medium were of 0.391/0.440 mg L-1, 0.069/0.192 mg L-1 and 0.033/0.068 mg L-1 for aldicarb, aldicarb sulfoxide and aldicarb sulfone, respectively. Total time of analysis was of 22 min. In the application of the method, the aldicarb degradation in horizontal-flow anaerobic immobilized biomass (HAIB) reactor was evaluated under different conditions (methanogenic, sulfidogenic and denitrifying).Este trabalho descreve o desenvolvimento e validação de um método de detecção de aldicarbe e seus metabólitos por cromatografia líquida de alta eficiência (HPLC) em amostras líquidas sem pré-tratamento. O sistema HPLC foi equipado com coluna C-18 e fase móvel composta de água e acetonitrila empregando gradiente de eluição linear. O detector UV foi operado em 210 nm. Metomil foi utilizado como padrão interno. Água e meio sintético foram utilizados como solventes. O método foi linear de 0,49-15,0 mg L-1 (r² > 0,9985), 0,1-5,0 mg L-1 (r² > 0,9974) e 0,1-5,0 mg L-1 (r² > 0,9987) para o aldicarbe, sulfóxido de aldicarbe e sulfona de aldicarbe, respectivamente. A linearidade do método foi confirmada pelo teste F (ANOVA) através dos testes de ajuste do modelo linear, validade da regressão e eficiência da regressão. Os limites de detecção na água e em meio sintético foram de 0,391/0,440 mg L-1, 0,069/0,192 mg L-1 e 0,033/0,068 mg L-1 para o aldicarbe, sulfóxido de aldicarbe e sulfona de aldicarbe, respectivamente. O tempo total de análise foi de 22 minutos. Na aplicação do método, avaliou-se a degradação do aldicarbe no reator anaeróbio horizontal de leito fixo (RAHLF) em diferentes condições operacionais (metanogênese, sulfetogênese e desnitrificação).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Young Women and Consumer Culture

This article is presented as an intervention in the field of feminist media and cultural studies with particular reference to consumer culture. It is concerned with the seeming evasion of critique which can be detected in a number of recent feminist responses to the way in which modalities of ‘popular feminism’ have found themselves incorporated into women's genres of television, such as, in particular, the US series Sex in the City. This usage or instrumentalization of feminism (in its most conventionally liberal feminist guise) also provides corporate culture with the means of presenting itself to young women as their ally and even champion of ‘girls’ while at the same time earning seeming approval for adopting the mantle of social responsibility, which makes the concept of popular feminism more problematic than it first appeared. Such appropriation of popular feminist discourse by the commercial domain prompts a self-critique on the part of the author alongside an analysis of recent approaches toward consumer culture in cultural studies. The article continues by presenting a schematic account of how the commercial domain increasingly supplants state and public sector institutions in the intensity and dedication of its address to girls and young women. Whilst some may argue that the intersection of youthful femininity and the commercial sphere is not a new phenomenon, what is being explored here is the connection between this intensification of attention and the logic of current neo-liberal economic rationalities. The argument is, therefore, that it is by these means including the instrumentalization of a specific modality of ‘feminism’ that there emerges into existence a neo-liberal culture, with global aspirations, which has as its ideal subject the category of ‘girl’

Bacterial diversity from environmental sample applied to bio-hydrogen production

Environmental from tropical climate countries as sediments in standing waters are complex habitats which are able to provide favorable living conditions for manifold microbial species. The aim of this study was to evaluate the diversity of the anaerobic bacteria present in the sediment of the reservoir and its application in biological production of hydrogen gas. The anaerobic batch reactors showed a xylose consumption of 63.5% at 72 h of operation with yield of H-2 production of 0.3 (mol H-2/mol xylose) at 37 degrees C, pH 5.5. Molecular biology techniques used for genomic DNA extraction, cloning, sequencing and phylogenetic analyses of the sediment sampling revealed clones similar to the phyla Proteobacteria, Chloroflexi, Firmicutes, Deferribacteres, Fusobacteria, Cyanobacteria and uncultured bacteria, The analysis of DGGE revealed changes in microbial populations from the sediment and the anaerobic consortia of bacteria from the reactors fed with xylose. Anaerobic bacteria coming from the sediment, mainly rods forming endospores from Phylum Firmicutes were favored by the experimental conditions imposed and they were probably involved in the biologic process of the H-2 production. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Fermentative hydrogen production by microbial consortium

Heat pre-treatment of the inoculum associated to the pH control was applied to select hydrogen-producing bacteria and endospores-forming bacteria. The source of inoculum to the heat pre-treatment was from a UASB reactor used in the slaughterhouse waste treatment. The molecular biology analyses indicated that the microbial consortium presented microorganisms affiliated with Enterobacter cloacae (97% and 98%), Clostridium sp. (98%) and Clostridium acetobutyricum (96%), recognized as H, and volatile acids` producers. The following assays were carried out in batch reactors in order to verify the efficiencies of sucrose conversion to H-2 by the microbial consortium: (1) 630.0 mg sucrose/L, (2) 1184.0 mg sucrose/L, (3) 1816.0 mg sucrose/L and (4) 4128.0 mg sucrose/L. The subsequent yields were obtained as follows: 15% (1.2 mol H-2/mol sucrose), 20% (1.6 mol H-2/mol sucrose), 15% (1.2 mol H-2/mol sucrose) and 4% (0.3 mol H-2/mol sucrose), respectively. The intermediary products were acetic acid, butyric acid, methanol and ethanol in all of the anaerobic reactors. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Pesquisa e Desenvolvimento (CNPq

Terpenoids and Steroids from Trichilia Species

The methanol extract of stems of Trichilia claussenii yielded three new sesquiterpenoids: 14-hydroxyelemol, germacra-10(14)-en-9,11,15-triol and germacra-3,10(14)-dien-9,11-diol-4-carbaldehyde. Two known sesquiterpenoids beta-eudesmol, cryptomeridiol and the triterpenoid 22,25-dihydroxy-9beta,19-cyclolanost-23-en-3-one were also isolated. The dichloromethane extract from the leaves of T. lepidota afforded a mixture of hydrocarbons (C29H60, C31H64 and C33H68), a mixture of the sesquiterpenes caryophyllene and humulene epoxides, spathulenol, and a series of sterols: 24-methylene-12b-hydroxycholesterol, 24-methyl-12beta-hydroxycholest-4-en-3-one, 24-methylene-12beta-hydroxycholest-5-ene-3-palmitate; a mixture of 24-methylenecholesterol, campesterol, stigmasterol and beta-sitosterol; besides alpha-tocoferol and phytol. From the methanol extract it was isolated N-methyl-4-hydroxyproline. The structures of the isolated compounds were determined on the basis of spectroscopic analysis