Dual Radiation exposure

Effective dose was a parameter used to assess biological risk related to radiation exposure, from dual-energy X-ray absorptiometry (DXA). Children are a worst case estimate because they absorb higher doses than adults. With the exception of the hip scans in 1- and 5-year-old children, the effective doses were below the negligible individual dose limit of 1 mrem per year (Thomas et al, 2005). 

The cabinet system includes full radiation safety in the form of dual, forced breaking door interlocks so that there can be no risk of exposure outside the cabinet. Equally the system is equipped with emergency stops and red lights indicating when X-rays are on, in accordance with the international regulations. 

Pacansky et al. (1987) described the fabrication of dual-layer photoreceptors by radiation curing. The layers were coated with a polymerizable acrylate monomer or oligomer as the liquid component, then cured by a 175 kV electron beam or ultraviolet exposure. These methods were used for the preparation of generation layers containing bisazo and hydroxysquaraine pigments. 

Intensifying Screens and Lead Screens. Chemical intensifying screens may shorten exposure times by factors up to 200 however their use is not recommended because they decrease resolution. Lead screens, on the other hand, serve dual purposes they not only absorb a large amount of unwanted secondary radiation, but they also act as intensifying screens because secondary electrons are emitted by the lead upon impact of x-rays. Such screens, 0.005 in. thick, should be placed on either side of the film when exposures greater than 150 kV are used. 

The dual modes of uranium chemical and radiological toxicity are not usually separately identifiable by end point. The renal and respiratory effects from exposure of humans and animals to uranium are usually attributed to the chemical properties of uranium, while the theoretically potential excess cancers are usually attributed to the radiation properties of this substance. Although the net effects on the lungs and kidneys have been suggested to be a cooperative action of the chemical and radiation properties, with a complementary mechanism of action, this relationship has not been demonstrated experimentally (Ballou... 

Two very similar groups of kinases with apparent molecular masses in the 46-57 kDa and 38 kDa ranges, respectively, were soon discovered in experiments with stressful stimuli such as the application of protein biosynthesis inhibitors or exposure of cells to (unphysiological) ultraviolet (UV) radiation (UVC <280 nm) [38] or lipopolysaccharide [39,40]. These stress-activated protein kinases (SAPK) are also proline-directed kinases that are activated by dual phosphorylation. The phosphorylation motif, however, differs from that of the classical MAPK, and is Thr-Pro-Tyr and Thr-Gly-Tyr, respectively, in the two SAPK groups. 

Another mode of dual curing involves the simultaneous occurrence of free radical and cationic radiation-induced cross-linking polymerization of formulations containing appropriate initiators [20, 23, 28]. This method, which is called hybrid curing, leads to coatings with imique properties. A typical hybrid-cure system contains a diacrylate and a diepoxide, the former polymerizing by a free radical and the latter by a cationic mechanism. Exposure of the system to in-... 

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