The aim of this study was to investigate the effect of an abiotic factor, i.e., lead at various concentrations (low causing a hormesis effect and causing high toxicity effects), on the generation of signalling molecules in pea (Pisum sativum L. cv. Cysterski) seedlings and then during infestation by the pea aphid (Acyrthosiphon pisum Harris). The second objective was to verify whether the presence of lead in pea seedling organs and induction of signalling pathways dependent on the concentration of this metal trigger defense responses to A. pisum. Therefore, the profile of flavonoids and expression levels of genes encoding enzymes of the flavonoid biosynthesis pathway (phenylalanine ammonialyase and chalcone synthase) were determined. A significant accumulation of total salicylic acid (TSA) and abscisic acid (ABA) was recorded in the roots and leaves of pea seedlings growing on lead-supplemented medium and next during infestation by aphids. Increased generation of these phytohormones strongly enhanced the biosynthesis of flavonoids, including a phytoalexin, pisatin. This research provides insights into the cross-talk between the abiotic (lead) and biotic factor (aphid infestation) on the level of the generation of signalling molecules and their role in the induction of flavonoid biosynthesis.

The crystal structure of (R,R)-N-methyltartramic acid monohydrate is presented and compared with that of the parent compound, (R,R)-tartaric acid. Despite some conformational differences between the two molecules the packing is very similar, as it is dictated by the carboxyl rather than the amide function. Particular attention is paid to a mediated three-centre hydrogen bond as one of the packing motifs involving the alpha-hydroxycarboxyl moiety. The stability and geometry of such structures in the gas phase and in solution are examined via theoretical ab initio methods using the RHF/6-311++G** and RHF/6-311++G**/Onsager models, respectively. Liquid media, in particular those of high polarity, are found to stabilize the structures considerably.

The influence of the conditions and worktime on the waste vanadic catalyst amount This paper includes the research results of the vanadic catalyst study that was operated in PCC Rokita S.A. during a gaseous SO3 formation. The physical properties have been studied: mechanical strength, bulk density and grindability during the five-year cycle of the catalyst worktime. The studies presented underline the prediction of the amount of the formed vanadic waste material.

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The catalytic process of SO 2 to SO 3 oxidation is the main step of sulfuric (VI) acid formation. The sustained catalyst operating due to its structural and textural modifications could disturb the process course. This paper includes the influence of the vanadic catalyst worktime on SO 2 emission and the expected amount of the obtained waste material of the inactivated catalyst.