Distribution of T-2 and HT-2 toxins in milling fractions of durum wheat

The effect of processing on mycotoxin content in milling fractions has been investigated in 10 samples of durum wheat contaminated with T-2 and HT-2 toxins at levels ranging from 97 to 5,954 μg/kg (sum of T-2 and HT-2 toxins). Either naturally contaminated samples or samples artificially inoculated with Fusarium sporotrichioides under field conditions were used. A method based on liquid chromatography-tandem mass spectrometry coupled with immunoaffinity column cleanup was validated in-house for the simultaneous analysis of both toxins in a variety of matrices, including uncleaned wheat, cleaned wheat, screenings, bran, red dog, fine middlings, and semolina. Mean recoveries from samples spiked with T-2 and HT-2 toxins at levels of 100 μg/kg ranged from 85 to 107%, with relative standard deviations (RSDs) lower than 14%. The milling process led to an increase of T-2 and HT-2 toxin contents up to 13- and 5-fold in screenings and bran, respectively, compared with occurrence in the uncleaned wheat; however, an overall reduction of T-2 and HT-2 toxins by 54% (RSD, 20%) and 89% (RSD, 3%) was observed in cleaned wheat and in semolina, respectively.     

Effect of Edible Coating Process and Irradiation Treatment of Strawberry fragaria spp. on Storage-keeping Quality

ABSTRACT: Gamma-irradiation and various edible coatings were tested on fresh strawberries ( Fragaria spp. ) for keeping fruit quality and extending shelf life. Four coatings based on milk protein were evaluated. In 1 experiment, coating formulation based on caseinate and/or strawberries were irradiated using a ⁶⁰Co source. Both gamma-irradiation treatment and edible coating process significantly delayed (p ≤ 0.05) molds growth. Edible coating based on irradiated caseinate was more effective than that of unirradiated caseinate. In a 2nd experiment, 3 irradiated coatings based on calcium caseinate and whey proteins were evaluated. The coating formulation based on 1:1 caseinate-whey was found to be more effective than those based on calcium caseinate. Addition of calcium chloride or a mixture of pectin and agar increased the effectiveness of the coating by delaying molds' apparition.     

Electrochemical reduction of hexahydro-1,3,5-trinitro-1,3,5-triazine in aqueous solutions

Electrochemical reduction of RDX, hexahydro-1,3,5-trinitro-1,3,5-triazine, a commercial and military explosive, was examined as a possible remediation technology for treating RDX-contaminated groundwater. A cascade of divided flow-through cells was used, with reticulated vitreous carbon cathodes and IrO2/Ti dimensionally stable anodes, initially using acetonitrile/water solutions to increase the solubility of RDX. The major degradation pathway involved reduction of RDX to the corresponding mononitroso compound, followed by ring cleavage to yield formaldehyde and methylenedinitramine. The reaction intermediates underwent further reduction and/or hydrolysis, the net result being the complete transformation of RDX to small molecules. The rate of degradation increased with current density, but the current efficiency was highest at low current densities. The technique was extended successfully both to 100% aqueous solutions of RDX and to an undivided electrochemical cell.     

Life cycle assessment of a community hydroelectric power system in rural Thailand

Rural electrification and the provision of low cost, low emission technology in developing countries require decision makers to be well informed on the costs, appropriateness and environmental credentials of all available options. While cost and appropriateness are often shaped by observable local considerations, environmental considerations are increasingly influenced by global concerns which are more difficult to identify and convey to all stakeholders.Life cycle assessment is an iterative process used to analyse a product or system. This study iteratively applies life cycle assessment (LCA) to a 3 kW community hydroelectric system located in Huai Kra Thing (HKT) village in rural Thailand. The cradle to grave analysis models the hydropower scheme’s construction, operation and end of life phases over a period of twenty years and includes all relevant equipment, materials and transportation.The study results in the enumeration of the environmental credentials of the HKT hydropower system and highlights the need to place environmental performance, and LCA itself, in a proper context. In the broadest sense, LCA results for the HKT hydropower system are found to reflect a common trend reported in hydropower LCA literature, namely that smaller hydropower systems have a greater environmentally impact per kWh – perform less well environmentally - than larger systems. Placed within a rural electrification context, however, the HKT hydropower system yields better environmental and financial outcomes than diesel generator and grid connection alternatives.     

Aquifex aeolicus membrane hydrogenase for hydrogen biooxidation: Role of lipids and physiological partners in enzyme stability and activity

Hydrogenase I from the hyperthermophilic bacterium Aquifex aeolicus is a good candidate for biotechnological devices thanks to its ability to oxidize hydrogen at high temperature, even in the presence of oxygen and CO. In order to enhance the enzyme stability and the catalytic efficiency, we investigated the hydrogen oxidation process with hydrogenase I embedded in a physiological-like environment. Hydrogenase I partners in the metabolic chain, namely membrane quinone and cytochrome b, were purified and fully characterized. The complex hydrogenase I–cytochrome b was inserted into liposomes. Surface Plasmon Resonance revealed that quinone took part in the stabilization of the complex. By use of molecular modelization and electrochemistry analysis, enzyme stability has been demonstrated to be stronger and enzymatic efficiency to be five times higher when hydrogenase is embedded into the liposomes. This result raises the possibility of using hydrogenases as biocatalysts in fuel cells.     

Implication of scavenger receptors in the interactions between diesel exhaust particles and immature or mature dendritic cells

Background  

The exposure to pollutants such as diesel exhaust particles (DEP) is associated with an increased incidence of respiratory diseases. However, the mechanisms by which DEP have an effect on human health are not completely understood. In addition to their action on macrophages and airway epithelial cells, DEP also modulate the functions of dendritic cells (DC). These professional antigen-presenting cells are able to discriminate unmodified self from non-self thanks to pattern recognition receptors such as the Toll like Receptors (TLR) and Scavenger Receptors (SR). SR were originally identified by their ability to bind and internalize modified lipoproteins and microorganisms but also particles and TLR agonists. In this study, we assessed the implication of SR in the effects of DEP associated or not with TLR agonists on monocyte-derived DC (MDDC). For this, we studied the regulation of CD36, CXCL16, LOX-1, SR-A1 and SR-B1 expression on MDDC treated with DEP associated or not with TLR2, 3 and 4 ligands. Then, the capacity of SR ligands (dextran sulfate and maleylated-ovalbumin) to block the effects of DEP on the function of lipopolysaccharide (LPS)-activated DC has been evaluated.     

A longitudinal study of phonological processing skills in children learning to read in a second language.

English-speaking children (N?=?122) in French immersion classes participated in a 1-year longitudinal study of the relation between phonological awareness and reading achievement in both languages. Participants were administered measures of word decoding and of phonological awareness in French and in English as well as measures of cognitive ability, speeded naming, and pseudoword repetition in English only. The relation of phonological awareness in French to reading achievement in each of the languages was equivalent to that in English. These relations remained significant after partialing out the influences of speeded naming and pseudoword repetition. Phonological awareness in both languages was specifically associated with 1-year increments in decoding skill in French. These findings support the transfer of phonological awareness skills across alphabetic languages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optical communication and fiber design

Optical fiber has evolved from a not-so-transparent glass tube to an extraordinarily efficient transmission medium. It is now acknowledged as a central element of modern telecommunication being part of the whole optimization process to further improve transmission system performance and cost. In this paper, we briefly introduce transmission system optimization problematics as well as key fiber characteristics. We then review the elements of fiber design for optimized optical communication networks, including metropolitan, long and ultra-long haul applications and show how fibers have evolved over the last ten years to keep pace with more and more demanding requirement of transmission system.