Pulse positive streamer corona discharges in water solution with a different conductivity have been investigated in reactors with the needle-plate and coaxial electrode geometry. A special composite anode was used in the coaxial geometry. With such an anode hundreds of streamers were generated at each voltage pulse. Production of H, O and OH radicals by the discharge was proved by emission spectroscopy and formation of H 2 O 2 and degradation of phenol was demonstrated by chemical methods. Assuming that the broadening of the Hα line profile was caused by the dynamic Stark effect, plasma with an electron density over 10 18 cm −3 was generated during the initial phase of voltage pulse in the both reactors in spite of the very different electrode geometry and wave-forms of voltage pulses. Production of OH radicals was most effective at solution conductivity below 100 µS cm −1 .

The increasing number of scientific publications focusing on magnetic materials indicates growing interest in the broader scientific community. Substantial progress was made in the synthesis of magnetic materials of desired size, morphology, chemical composition, and surface chemistry. Physical and chemical stability of magnetic materials is acquired by the coating. Moreover, surface layers of polymers, silica, biomolecules, etc. can be designed to obtain affinity to target molecules. The combination of the ability to respond to the external magnetic field and the rich possibilities of coatings makes magnetic materials universal tool for magnetic separations of small molecules, biomolecules and cells. In the biomedical field, magnetic particles and magnetic composites are utilized as the drug carriers, as contrast agents for magnetic resonance imaging (MRI), and in magnetic hyperthermia. However, the multifunctional magnetic particles enabling the diagnosis and therapy at the same time are emerging. The presented review article summarizes the findings regarding the design and synthesis of magnetic materials focused on biomedical applications. We highlight the utilization of magnetic materials in separation/preconcentration of various molecules and cells, and their use in diagnosis and therapy.

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The objective of this study was to determine the influence of low-temperature plasma (LTP) on seed surface modification, water uptake by seeds, seed germination and vigor of seedlings, as well as changes in the content of endogenous hormones in pea, (Pisum sativum L. var. Prophet). The study's authors used diffuse coplanar surface barrier discharge as the source of LTP in various duration times of treatment (from 60 to 600 s). The SEM analysis showed that LTP induced significant changes on the seeds' surface, which was related to water permeability into the seeds. LTP increased the germination percentage of pea seeds as well as the growth parameters (root and shoot length, dry weight), and the vigor of seedlings and the effects of LTP also depended on exposure time. The LTP-pretreatment produced changes in endogenous hormones (auxins and cytokinins and their catabolites and conjugates), which correlated with increased growth of the pea seedlings. The results suggested an interaction among the modification of seed structure demonstrated by LTP in the induction of faster germination and hormonal activities related to plant signaling and development during the early growth of pea seedlings.