Nutrient element concentrations and grain quality were assessed in spring wheat grown under elevated CO 2 concentrations and contrasting levels of tropospheric ozone at different nitrogen supply rates at several European sites. Carbon dioxide enrichment proved to affect nutrient concentrations in a complex manner. In green leaves, all elements (with exception of phosphorus and iron) decreased. In contrast, effects on the element composition of grains were restricted to reductions in nitrogen, calcium, sulphur and iron. Ozone exposure resulted in no significant effects on nutrient element concentrations in different tissues in the overall analysis. The nitrogen demand of green tissues was reduced due to CO 2 enrichment as shown by reductions in the critical leaf nitrogen concentration and also enhanced nitrogen use efficiency. Reductions in the content of ribulose-bisphosphate carboxylase/oxygenase and repression of the photorespiratory pathway and reduced nitrogen allocation to enzymes driving the photosynthetic carbon oxidation cycle were chiefly responsible for this effect. Thus, nitrogen acquisition by the crop did not match carbon acquisition under CO 2 enrichment. Since crop nitrogen uptake from the soil was already completed at anthesis, nitrogen allocated to the grain after anthesis originated from vegetative pools-causing grain nitrogen concentrations to decrease under CO 2 enrichment (on average by 15% when CO 2 concentrations increased from 360 to 680 mmol mol−1). Correspondingly, grain quality was reduced by CO 2 enrichment. The Zeleny value, Hagberg value and dry/wet gluten content decreased significantly with increasing [CO 2 ]. Despite the beneficial impact of CO 2 enrichment on growth and yield of C 3 cereal crops, declines in flour quality due to reduced nitrogen content are likely in a future, [CO 2 ]-rich world.

Observational studies with unmatched patients were the best available evidence which limited comparability and resulted in risk of selection bias and confounding by indication. Diverticular abscesses with diameters less than 3 cm might be sufficiently treated with antibiotics, while the best treatment for larger abscesses remains uncertain. Acute surgery should be reserved for critically ill patients failing non-operative treatment. Further research is needed to determine the best treatment for different sizes and types of diverticular abscesses, preferably randomized controlled trials.

The deoR gene, which encodes the deor repressor protein in Escherichia coli, was fused to the strong Ptrc promoter in plasmid pKK233‐2. The Ptrc promoter is kept repressed by lacI repressor to prevent cell killing. Induction of the Ptrc–deoR fusion plasmid resulted in the accumulation of 4% of the soluble protein as deoR protein. The deoR repressor protein was purified to 80% purity using conventional techniques; it has a mass of 28.5 kd and appears to exist as an octamer in solution. The deoR repressor is shown by DNase I footprinting to bind to the 16 bp palindromic sequence in the Pribnow box region of the deoP1 promoter. Also, the deoR repressor binds cooperatively in vitro to a DNA template with two deoR binding sites separated by 224 bp in keeping with the conclusion from genetic experiments that more than one operator is required for efficient repression of the deo operon.

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