Fusarium mycotoxins in Lithuanian cereals from the 2004-2005 harvests

Fusarium mycotoxins deoxynivalenol (DON), T-2 toxin, and zearalenone (ZEN) contamination in 5 kinds of cereal grain harvested in 2004 and 2005 in different regions of Lithuania was examined for their occurrence frequency and level. In all cereal species DON was the most frequently detected mycotoxin with an incidence rate of 98.0 - 100% and range in positive samples from traces to 691 μg kg-1 in 2004 and 62.5-94.0%, range from traces to 1,121 μg kg-1 in 2005, respectively. All the tested oat samples collected in 2004-2005 were found to be contaminated with the T-2 toxin. In one sample from the year 2004 the level of T-2 toxin (121.5 μg kg-1) exceeded the allowable level. In 2004, ZEN contamination was more frequent in spring wheat, barley and oats grain, whereas in 2005 this toxin was identifi ed at higher levels only in barley grain (68.0%). In one barley grain sample from 2004, ZEN content (193.4 μg kg-1) exceeded the allowable level. Variation in the relative air-humidity exerted some effect on the incidence of Fusarium spp. fungi and mycotoxin content in wheat grain. The weather conditions at harvesting contributed to an increase in the contents of Fusarium fungi and DON and ZEN mycotoxins produced by them in winter wheat grain. This risk factor increases the threat to human and animal health

Investigation of spin-polarized carrier injection effect in|YBa2Cu3O7/SrTiO3/La0.67/Sr0.33MnO3 and YBa2Cu3O7/La0.67Sr0.33MnO3 heterostructures

We report preparation and electrical properties of the YBa2Cu3O7SrTiO3(d ≈ 5.0 nm)/La0.67Sr0.33MnO3 (YBCO/STO/LSMO) and YBCO/LSMO multilayer structures grown heteroepitaxially on LaAlO3(100) substrates by single source pulsed injection MOCVD. The heterostructures were patterned in a cross-strip geometry to perform electrical measurements at T=78/300 K under magnetic field μ0H= 0/16 T using 4-probe dc method. Suppression of a supercurrent of the patterned YBCO stripes was indicated for the YBCO/LSMO heterostructure by injecting tunneling spin-polarized current fiom the underlying FM layer. The transport effects were modelled taking into account current redistribution in the adjacent conducting HTS and FM layers

Valence states of metal ions in La0.7Ce0.3MnO3La_{0.7}Ce_{0.3}MnO_{3} thin films

We report valence states of ions in $La_{0.7}Ce_{0.3}MnO_3$ thin films grown by a reactive dc magnetron sputtering. The measurements were performed by means of high-energy X-ray photoelectron spectroscopy using synchrotron radiation. It was found that Ce ion in the compound is either in tetravalent or trivalent chemical state, manganese is in divalent, trivalent and tetravalent states, while La ion existing in oxide and hydroxide chemical species is in trivalent state