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Short-fibre paper residuals (deinking paper fibre (DPF) or paper mill sludge) represents a major waste formed during the processing of recycled paper and is known to contain significant quantities of copper. It is often spread onto agricultural land to help increase soil pH and improve structure by adding soil organic matter (SOM). A number of agricultural sites in England and Wales that had received large and repeated applications were sampled to investigate the long-term effects of this practice on soil quality and plant copper content. We found that the composition of DPF waste has changed significantly between 1999 and 2006 with concentrations of Cu increasing and organic matter content declining. Whilst repeated additions of DPF to agricultural land always increased soil Cu, an associated increase in SOM was not always apparent. There was no link between SOM and bioavailable Cu nor between soil bioavailable Cu and plant Cu. In contrast to previous reports, our findings indicate that improvement in soil quality following the long-term application of DPF was site-specific and in some cases it may have reduced soil quality rather than enhanced it. [ABSTRACT FROM AUTHOR]

Candidate HIV vaccines must show an immune response in order to be considered for further testing and development. What constitutes a “response,” however, is still not clear. While the hunt for a protective vaccine continues, hypotheses are being formed by studying the immune responses across cohorts of people with differing responses to the infection, as well as the immune responses formed by healthy people to other viruses, ones that are generally common and well controlled. Here we examine the functional profile of the immune responses of a group of HIV + long-term non-progressors as measured by intracellular cytokine staining using polychromatic flow cytometry, and compare these responses to those of a larger group of other HIV + people. We describe some of the types of patterns in immune response that are of interest to vaccine researchers, and compare several statistical tests appropriate for this type of data. [ABSTRACT FROM AUTHOR]

We have explored the relationships between specific leaf area calculated for a whole plant and its individual leaves. Barley was grown in hydroponics in controlled environment cabinets. Plants were harvested on the basis of physiological age (defined as the number of days after full expansion of leaves on the main stem) and the area and weight of whole, fully expanded, leaves measured and specific leaf area (SLA) of individual leaves or whole plants calculated. Specific leaf area calculated for individual leaves ( SLAL) varied with leaf position and with leaf age after full expansion whereas SLA calculated for whole plants (SLAP) varied with plant age. The same conclusions were reached whether the results were based on total dry weight or dry weight minus soluble carbohydrates ('structural weight'). Transferring plants to shade on the day of full expansion of the third leaf on the main stem increased the SLAP, and also SLAL of leaves 3 and 4 on the main stem (leaf 4 being the younger leaf of the two), because of a decrease in the 'structural weight` of these leaves. However SLA1 of leaf 2 (which was older than leaf 3) was not affected by shading: the effect was confined to leaves developing in the new conditions. [ABSTRACT FROM AUTHOR]