A microbial fuel cell in contaminated ground delineated by electrical self-potential and normalized induced polarization data

There is a growing interest in the use of geophysical methods to aid investigation and monitoring of complex biogeochemical environments, for example delineation of contaminants and microbial activity related to land contamination. We combined geophysical monitoring with chemical and microbiological analysis to create a conceptual biogeochemical model of processes around a contaminant plume within a manufactured gas plant site. Self-potential, induced polarization and electrical resistivity techniques were used to monitor the plume. We propose that an exceptionally strong (>800 mV peak to peak) dipolar SP anomaly represents a microbial fuel cell operating in the subsurface. The electromagnetic and electrical geophysical data delineated a shallow aerobic perched water body containing conductive gasworks waste which acts as the abiotic cathode of microbial fuel cell. This is separated from the plume below by a thin clay layer across the site. Microbiological evidence suggests that degradation of organic contaminants in the plume is dominated by the presence of ammonium and its subsequent degradation. We propose that the degradation of contaminants by microbial communities at the edge of the plume provides a source of electrons and acts as the anode of the fuel cell. We hypothesize that ions and electrons are transferred through the clay layer that was punctured during the trial pitting phase of the investigation. This is inferred to act as an electronic conductor connecting the biologically mediated anode to the abiotic cathode. Integrated electrical geophysical techniques appear well suited to act as rapid, low cost sustainable tools to monitor biodegradation.

Neolithic Diet at the Brochtorff Circle Malta

Richards, M., Hedges, R., Walton, I; Stoddart, S., Malone, C.,

Interleukin-4 and interleukin-4 soluble receptor α levels in bronchoalveolar lavage from children with asthma

Background: In asthma there is increased expression of the Th2-type cytokine interleukin-4 (IL-4). IL-4 is important in immunoglobulin isotype switching to immunoglobulin E and adhesion of eosinophils to endothelium.

Objectives: We hypothesized that levels of IL-4 in bronchoalveolar lavage (BAL) fluid would be increased in stable, atopic asthmatic children compared with controls and that levels of its physiologic inhibitor IL-4 soluble receptor α (IL-4sRα) would be correspondingly decreased.

Methods: One hundred sixteen children attending a children's hospital for elective surgery were recruited. A nonbronchoscopic BAL was performed, and IL-4 and IL-4sRα were measured in the BAL supernatants.

Results: There was no significant difference in IL-4 concentrations between atopic asthmatic children, atopic normal controls, and nonatopic normal controls [0.13 pg/mL (0.13 to 0.87) vs 0.13 pg/mL (0.13 to 0.41) vs 0.13 pg/mL (0.13 to 0.5), P = 0.65]. IL-4sRα levels were significantly increased in asthmatic patients compared with atopic controls [6.4 pg/mL (5.0 to 25.5) vs 5.0 pg/mL (5.0 to 9.9), P = 0.018], but not when compared with the nonatopic controls [5.2 pg/mL (5.0 to 10.6), P = 0.19].

Conclusions: Contrary to expectation, IL-4sRα levels are increased in BAL from stable asthmatic children compared with nonatopic controls, and we speculate that IL-4sRα is released by inflammatory cells in the airways to limit the proinflammatory effects of IL-4.

List 229: Irish and English Dendrochronology

These results cover dating undertaken since the last published list of dated building from Ireland (Brown (2002)); one English church building is also included in the list. Thanks are due to the owners of the buildings and especially to everyone who assisted in taking of the samples: Phil Barrett, Sapphire Mussen, Charles Lyons, Jon Pilcher and Mike Baillie, Amanda Pedlow, Caimin O’Brien and Martin Timoney. Most of the descriptions of the buildings are taken from the National Inventory of Architectural Heritage http://www.buildingofi reland.ie/. The correlation values were generated by CROSS84 (Munro, 1984), which provides a signifi cance level for the date to be correct; *** (extremely signifi cant), ** (very signifi cant), * (signifi cant), nsm (not signifi cant). Estimated felling date ranges are based on the Belfast sapwood estimate of 32 ± 9 years. Date ranges have been calculated by adding and subtracting 9 years from the calculated estimated felling dates. Timbers from the following buildings could not be dated. Cork: St Finbarre’s Cathedral (W 675 715); Dublin: Christchurch Cathedral (O 152 341); Galway: Cloghan Castle (M 972 119); Kilkenny: Rothe House (S 506 563); Offaly: Boveen House (S 075 956); Waterford: Christchurch Cathedral (S 616 121). Generally only single oak samples were recovered from these structures. References: D.Brown, ‘Dendrochronological dating building from Ireland’, VA 33 (2002), 71–3; M. Munro, ‘An improved algorithm for crossdating tree-ring series’, Tree-Ring Bulletin 44 (1984), 17–27.