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Ripening of blue-veined cheeses, such as the French Bleu and Roquefort, the Italian Gorgonzola, the English Stilton, the Danish Danablu or the Spanish Cabrales, Picón Bejes-Tresviso, and Valdeón, requires the growth and enzymatic activity of the mold Penicillium roqueforti, which is responsible for the characteristic texture, blue-green spots, and aroma of these types of cheeses. This filamentous fungus is able to synthesize different secondary metabolites, including andrastins, mycophenolic acid, and several mycotoxins, such as roquefortines C and D, PR-toxin and eremofortins, isofumigaclavines A and B, and festuclavine. This review provides a detailed description of the main secondary metabolites produced by P. roqueforti in blue cheese, giving a special emphasis to roquefortine, PR-toxin and mycophenolic acid, and their biosynthetic gene clusters and pathways. The knowledge of these clusters and secondary metabolism pathways, together with the ability of P. roqueforti to produce beneficial secondary metabolites, is of interest for commercial purposes.

The current literature shows great interest in the issue of gender diversity on boards of directors. Some studies have hypothesized a direct relationship between diversity and the value of the firm, but not many examine the intermediate mechanisms that may exert an influence on such relationships. We employ two stages of GMM estimation methodology to exhibit evidences of the relationship between gender diversity and compensation of top managers in the Spanish context. Results show that gender diversity positively affects the effectiveness of boards—in terms of composition, structure, size and functioning—influencing a proper design of top managers compensation linked to company performance. Evidences suggest that legislative actions aimed at increasing the presence of women on boards of directors are justified not only for ethical reasons, but also for reasons of economic efficiency.

The aim of this work is to establish the correlation between the transcriptional activator PTA1 and the expression of the penicillin genes in different penicillin-producing strains. The level of expression of the first two genes of the penicillin pathway was clearly higher in Penicillium chrysogenum than in Penicillium notatum and Penicillium nalgiovense. The divergent promoter pcbAB-pcbC region contains binding sequences for several transcriptional factors that are conserved in P. notatum and P. chrysogenum, but not in P. nalgiovense. Binding of the purified P. chrysogenum transcriptional activator PTA1 to the palindromic heptamer TTAGTAA took place when the P. chrysogenum 35 bp DNA fragment containing the heptamer was used as a probe, but not when the sequence occurring in P. nalgiovense was used. P. nalgiovense protein fractions purified by heparin agarose chromatography did not bind to the 35-bp DNA fragment either from P. nalgiovense or P. chrysogenum, although some degree of binding was observed when crude extracts were used. This finding may explain the low expression of pcbC in P. nalgiovense. All the P. chrysogenum strains, including the industrial strain E1, showed the same nucleotide sequence, including the consensus PTA1 binding site.

This paper analyses some of the empirical implications of the pecking order theory in the Spanish market using a panel data analysis of 1,566 firms over 1994–2000. The results show that the pecking order theory holds for most subsamples analyzed, particularly for the small and medium-sized enterprises and for the high-growth and highly leveraged companies. It is also shown that both the more and the less leveraged firms tend to converge towards more balanced capital structures. Finally, we observe that firms finance their funds flow deficits with long term debt.

The solubility limits of MgO in tetragonal zirconia were studied by combining the differential thermal analysis data and X-ray disappearing phase method. From these experiments a eutectoid reaction, tetragonal ZrO2 solid solution → monoclinic ZrO2 solid solution + MgO, at 1120±10 °C and 1.6±0.2 mol% MgO was established. The solubility of MgO in tetragonal ZrO2 diminished as the temperature increased, and at 1700 °C the solubility was less than 0.5 mol% MgO. The extent of the cubic zirconia solid solution single field was determined by using precise lattice parameter measurements and SEM observations. In this way an invariant eutectoid point, cubic ZrO2 solid solution → tetragonal ZrO2 solid solution + MgO, was located at 1420±10 °C and 14.8±0.5 mol% MgO.

An improved HPLC method is described to separate isopenicillin N from its penicilloic acid and from the reduced and oxidized forms of δ -(L-α-amino-adipyl)-L-cysteinyl-D-valine and of DTT. When applied to assay the activity of isopenicillin N synthase only isopenicillin N and its penicilloic acid could be detected.

From co-precipitated powder samples, the solid state reactions occurring between room temperature and 1500° C in the ZrO2-CaO system have been studied. At low temperatures, compositions containing < 25 mol% CaO show a complex picture of phase transformation and ordering in the system. From the obtained results the following singular reactions have been established. (i) Tetragonal zirconia solid solution decomposes eutectoidally at 7 mol% CaO and 1048 ± 4° C into monoclinic zirconia solid solution and calcium zirconate (CZ). (ii) Cubic zirconia solid solution undergoes a eutectoidal decomposition at 17.5 mol% Cao and 1080 ±20° C into tetragonal solid solution + calcium zirconate. (iii) The monoclinic ordered phase, CaZr4O9 (Φ1), ), undergoes an order-disorder transformation into cubic zirconia solid solution at 1232 ± 5° C. (iv) Cubic zirconia solid solution undergoes a eutectoidal decomposition into two ordered phases, Φ1 + Φ2 at 21 mol% CaO and 1200 ± 10°C. (v) Hexagonal ordered phase Ca6Zr19O44 (Φ2) decomposes peritectoidally into cubic zirconia solid solution + calcium zirconate at 1360 ± 10° C. The two ordered phases Φ1 and Φ2 seem to be unstable below ≈ 1100° C. By using DTA, X-ray diffraction and SEM techniques, the extent of the tetragonal and cubic zirconia solid solution fields have been established. From the above experimental results a new tentative phase diagram is given for the ZrO2-rich region of the system, ZrO2-CaO.