[en] Heparin, when added to citrated platelet-rich plasma (PRP), caused potentiation of platelet aggregation and the release reaction induced by the aggregating agents adenosine diphosphate (ADP), arachidonic acid, collagen, and epinephrine. At low concentrations (4.7 x 10(-5) M) arachidonic acid failed to cause aggregation of platelets in citrated PRP. However, in the presence of heparin, the same concentration of arachidonic acid caused aggregation. Examination of PRP for the presence of thromboxane A2 (TxA2) by use of a bioassay revealed that heparin also stimulated release of TxA2. This finding indicated that platelets released more TxA2 when they were challenged by low concentrations of arachidonic acid in the presence of heparin than in its absence. Platelets were labeled with ³H-arachidonic acid and ¹⁴C-serotonin, and attempts were made to determine whether heparin stimulated the platelet release reaction first with subsequent increased production of TxA2, or alternatively, whether heparin stimulated TxA2 production first with subsequent enhancement of the release reaction. In view of the demonstrated simultaneous release of ¹⁴C-serotonin and ³H-arachidonic acid metabolites, it appeared that either release of ¹⁴C and ³H occurs concurrently or, even if one of these events is dependent on the other, both events take place in rapid succession. Timed sequential studies revealed that in the presence of arachidonic acid, the addition of heparin hastened the apparently simultaneous release of both ¹⁴C and ³H

[en] Transportation of hazardous materials, and particularly radioactive wastes, on public highways has become an important risk management issue. The unfavorability of public attitudes regarding hazardous and nuclear waste signals the potential for strong public opposition to programs for transporting these materials. This paper presents the results of a survey conducted to assess public reactions to a long-term nuclear waste transport program planned to follow a route through a portion of rural Oregon. The survey assessed a number of key risk perception issues, including perceived health and safety risks of nuclear waste transport, relative risks of transport vs. storage at an existing site, trust in state officials, and satisfaction with life in communities along the transport route. The survey identified a number of attitudes and concerns that need to be understood and considered by those in charge of designing and implementing the waste-transportation program. 22 refs., 1 fig., 5 tabs

[en] Plantwide digital radiation monitoring systems (RMSs) have been generally installed as part of the original design for newer nuclear reactors. For older plants, area and process radiation monitors were either analog or a combination of analog and digital but were not part of an integrated system design. At some plants, individual monitors have been replaced or modified, resulting in a rainbow of different monitors and vendors being represented at the plant. Usually at some point, consideration is given to replacing these monitors with a state-of-the-art RMS to improve overall reliability and achieve the benefits of sound human factors engineering. This can be a very costly project in terms of expenditures for engineering, equipment, construction, startup, and time. When human engineering deficiencies (HEDs) became an issue at Zion station, Commonwealth Edison elected to install a computer-based radiation monitoring display system (RMDS) that would interface existing raidation monitors. After reviewing the existing as-built RMS configuration and internal circuits of the various monitors, it was concluded that a microprocessor-based RMDS could be successfully designed and installed that would solve the HEDs and would tie the older analog channels into a system configuration. Although in many cases, internal modifications were made to existing RMS monitors, the RMDS upgrade allowed the existing RMS monitors to retain their original functionality and location