Ein technisches Informationssystem zur verbesserten betrieblichen Überwachung des Kernkraftwerkes Saporoshje/Ukraine

In order to improve the operational surveillance of a VVER-1000 unit of the Ukrainian nuclear power plant Zaporosh´ye a technical monitoring system has been specified. The system will enable the state regulatory and supervisory bodies to survey the unit operation independently of operators to assess its safety status, and to impose appropriate conditions. Due to its up-to-date configuration the system provides early indication of any operational incident and emission of radioactive materials connected. Based on the system an immediate warning in mergency situations is possible as well as an effective emergency management. For this purpose 49 different operational parameters of the unit, 18 radiological parameters of the unit and the plant site and 6 meteorological parameters are monitored. The monitoring concept and its technical realization are described

Perfluorocarbon Particle Size Influences Magnetic Resonance Signal and Immunological Properties of Dendritic Cells

The development of cellular tracking by fluorine (19F) magnetic resonance imaging (MRI) has introduced a number of advantages for following immune cell therapies in vivo. These include improved signal selectivity and a possibility to correlate cells labeled with fluorine-rich particles with conventional anatomic proton (1H) imaging. While the optimization of the cellular labeling method is clearly important, the impact of labeling on cellular dynamics should be kept in mind. We show by 19F MR spectroscopy (MRS) that the efficiency in labeling cells of the murine immune system (dendritic cells) by perfluoro-15-crown-5-ether (PFCE) particles increases with increasing particle size (560>365>245>130 nm). Dendritic cells (DC) are professional antigen presenting cells and with respect to impact of PFCE particles on DC function, we observed that markers of maturation for these cells (CD80, CD86) were also significantly elevated following labeling with larger PFCE particles (560 nm). When labeled with these larger particles that also gave an optimal signal in MRS, DC presented whole antigen more robustly to CD8+ T cells than control cells. Our data suggest that increasing particle size is one important feature for optimizing cell labeling by PFCE particles, but may also present possible pitfalls such as alteration of the immunological status of these cells. Therefore depending on the clinical scenario in which the 19F-labeled cellular vaccines will be applied (cancer, autoimmune disease, transplantation), it will be interesting to monitor the fate of these cells in vivo in the relevant preclinical mouse models

Traps in Zirconium Alloys Oxide Layers

Oxide films long-time grown on tubes of three types of zirconium alloys in water and in steam were investigated, by analysing I-V characteristic measured at constant voltages with various temperatures. Using theoretical concepts of Rose [3] and Gould [5], ZryNbSn(Fe) proved to have an exponential distribution of trapping centers below the conduction band edge, wheras Zr1Nb and IMP Zry-4 proved to have single energy trap levels