Toxicity of mono-, di- and tri-chlorophenols to lux marked terrestrial bacteria, Burkholderia species Rasc c2 and Pseudomonas fluorescens

Burkholderia species RASC and Pseudomonas fluorescens were marked with lux genes, encoding for bioluminescence and used to assess the toxicity of mono-, di- and tri-chlorophenols by determining the decline in bioluminescence following exposure to the compounds in aqueous solution. Toxicity was expressed as a 50% effective concentration value (EC50, equating to the concentration of compound which caused a 50% decline in bioluminescence. Comparing the toxicity values of the compounds showed that, in general, increasing the degree of chlorination, increased toxicity. By carrying out forward multiple linear regressions with log10 EC50 values and physio-chemical descriptors, it was shown that molecular parameters describing the hydrogen bonding nature of a chlorophenol provided a better fit than regressions between toxicity data and log10 Kow alone. Utilising these descriptor variables in equations, it was shown that the toxicity of chlorophenols to the lux marked bacteria could be predicted from the compounds physio-chemical characteristics. By correlating lux marked RASC c2 and P. fluorescens EC50 values with toxicity values using Pimephales promelas (fathead minnow), Tetrahymena pyriformis (ciliate) and marine bacterium Vibriofischeri, it was apparent that lux marked RASC c2 correlated well with the freshwater aquatic species (P. promelas and T. pyriformis). This implied that for predictions of toxicity of organic xenobiotic compounds to higher organisms, lux marked RASC c2 could be utilised as a rapid surrogate.

Use of MIR Spectroscopy for Optimisation of Biogas Plants

MIR spectroscopy is an established technique which has process monitoring applications in the chemical and pharmaceutical industries. Previous attempts to utilise the technology for monitoring of AD plants were of limited success, with operation hindered by severe clogging of the probe.

Novel fittings, which allow a probe to be withdrawn from the process fluid, cleaned and recalibrated in situ have now been developed to combat this clogging problem. This has allowed a spectroscopic probe to be used successfully in lab scale digesters for real time measurement of VFA concentration, a key parameter to the stability of AD plants.

This project will demonstrate the technology at a farm scale AD plant for the first time. Both real-time measurements of VFA concentrations and parameters currently measured by plant operators will be available, leading to state-of-the-art monitoring and control of the AD plant. With the improved monitoring that this probe will deliver, it is hoped to realise a 10% increase in biogas production without compromising the stability of the process. This will deliver both economic and environmental benefits.

Le origini di Gubbio (Gubbio, Italy):The origins of Gubbio

6 month exhibition in Palazzo dei Consoli, Gubbio consisting of major archaeological discoveries and c.250 objects+ text and photographs.

Il Neolitico di Umbria - gallery, San Marco Gubbio.:Neolithic text and selection of material for display and interpretation

2009-10 Perugia – provision of material and data for gallery and information panels in Perugia Museo dei Provincia

Nota preliminare sui nuovi scavi a Monte Ingino - La Rocca Posteriore sul Monte Ingino di Gubbio. (Campagne di scavo 1975-77):"La Nuova Italia

Flavell, P., C.A.T. Malone, and S.K.F. Stoddart, (eds.)..( ed.). G. Meloni. 1987," Editrice - Regione dell'Umbria, : Firenze - Perugia.