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[en] For the case of materials bombarded by atomic or ionic forms of hydrogen, approximate analytic solutions are obtained for the time-dependent retention and release of hydrogen. Simple physical pictures of the retained hydrogen concentrations are obtained and are found to yield results in good agreement with those from computer codes such as PERI. (orig.)
[en] Objective: To study the retention pattern of radioiodine in rat thyroid, observe the biological effect, and assess the harm of radioiodine in human being. Methods: By means of whole body counting, metabolic parameters of radioiodine for the rat thyroid were obtained. The retention equation of iodine in rat thyroid was of a three-exponential function. Results: By using the three-exponential function, the average accumulated absorbed doses of radioiodine for rat thyroid were estimated to be 7.7 Gy and 11.5 Gy, respectively. Compared with this method, the ordinary method overestimated the absorbed dose by 66%-91%. Conclusion: Considering some factors affecting the dose of radioiodine in rat thyroid after injection, this method can estimate the absorbed dose of radioiodine after injection for rat thyroid of different ages
[en] The purpose of this study was to determine the performance of two balloon-retention-type gastrostomy tubes when the balloons are inflated with two types of contrast materials at different concentrations. Two commonly used balloon-retention-type tubes (MIC and Tri-Funnel) were inflated to the manufacturer's recommended volumes (4 and 20 cm3, respectively) with normal saline or normal saline plus different concentrations of contrast material. Five tubes of each brand were inflated with normal saline and 0%, 25%, 50%, 75%, and 100% contrast material dilutions, using either nonionic hyperosmolar contrast, or nonionic iso-osmolar contrast. The tubes were submerged in a glass basin containing a solution with a pH of 4. Every week the tubes were visually inspected to determine the integrity of the balloons, and the diameter of the balloons was measured with a caliper. The tests were repeated every week for a total of 12 weeks. The MIC balloons deflated slightly faster over time than the Tri-Funnel balloons. The Tri-Funnel balloons remained relatively stable over the study period for the different concentrations of contrast materials. The deflation rates of the MIC balloons were proportionally related to the concentration of saline and inversely related to the concentration of the contrast material. At high contrast material concentrations, solidification of the balloons was observed. In conclusion, this in vitro study confirms that the use of diluted amounts of nonionic contrast materials is safe for inflating the balloons of two types of balloon-retention feeding tubes. High concentrations of contrast could result in solidification of the balloons and should be avoided.
[en] Nineteen patients with progressive systemic sclerosis were underwent radioisotope esophageal transit study (RIETS) which revealed abnormal transit time and/or pattern in 16 (84.2%). Among them 12 showed to and fro movement of RI and 4 showed retention of it. Abnormal esophageal transit was not related with Raynaud phenomenon. After intravenous administration of metaclopramide (10 mg), percent retention of RI in distal 2/3 of esophagus was significantly reduced (p<0.05).
[en] Skill-mix initiatives have provided opportunities for radiographers to develop roles and achieve their potential, thus contributing to radiographer retention rates and increased job satisfaction. This reflective article explores two radiographic roles within an interprofessional context including the implications for confidence, competence, and future sustainability. These were reporting roles which extended into two modalities, one into bone densitometry and another into ultrasound. This article discusses how successful skill mix can benefit the individual, their department, and NHS organization and that role expansion can develop a more dynamic and resourceful workforce with transferability of skills and attributes
[en] The urinary excretion database built up at Sellafield since the early 1950s was made available for analysis as part of a research programme into plutonium biochemistry. A set of cases was selected for which the data were adequate to support analysis based on a standard pharmacokinetics approach. Cases include exposures from both inhalation and wound deposition, and from plutonium nitrate, oxalate and metal. Data sets extended from 12 years post-exposure up to 25+ year post-exposure. The pharmacokinetics approach was found to be valuable, calling into question certain aspects of ICRP methodology and highlighting areas where further research is required. In particular, it suggested that the distribution equilibrium phase, reached within 3 to 4 years post-exposure, was followed by a terminal equilibrium phase with a half-life of some 12 years. This long-term half-life, which was much shorter than those in ICRP models, persisted for over 20 years in some cases. (author)
[en] Juvenile mosquitofish, Gambusia affinis, were reared in an environment uniformly labeled with 65Zn until they attained the specific activity of the environment. Retention of 65Zn in these fish was followed with time in a non-labeled environment. Analysis of the retention curve yielded three mathematical reservoirs of stable Zn each containing 8.72, 4.30 and 91.1% of the element with measured rate constants of 0.280, 0.0510 and 0.00295 days-1, respectively, unbiased by lack of uniform labeling of the organisms. (author)
[en] On the 6-7 June 2016, IRSN hosted an international workshop about the “Strategy of In-Vessel Melt Retention: Knowledge and Perspectives”. The workshop was co-organized by JRC and IRSN, with the sponsorship of ETSON. With panel discussions and technical sessions, the workshop covered all the important issues related to in-vessel corium retention, from the physical understanding to regulatory frames. The major points of the safety demonstration were discussed. Some industrial aspects were also addressed. One of the objectives was to provide an orientation of R&D projects to strengthen IVR strategies, such as the H2020 IVMR project, coordinated by IRSN. The current approach followed by most experts for IVR is a compromise between a deterministic approach using the significant knowledge gained during the last two decades and a probabilistic approach to take into account large uncertainties due to lack of data for some phenomena and due to excessive simplifications of models. It was concluded that a harmonization of the positions of safety authorities on the IVR strategy is necessary to allow decision making based on scientific knowledge. For this, a consensus on several issues should be reached between R&D experts. This includes in particular the issues of the transient evolution of oxide and metal layers in the lower plenum and of the long term mechanical behavior of the thin “cold shell” resulting from vessel ablation. (author)
[en] The effect of Ipriflavon ((7-isopropoxy-isoflavon) and Morin (2',3,4',5,7-pentahydroxy-flavon) on the retention and elimination of 85Sr in normal and pregnant rats was studied. It was established that 85Sr could beneficially be mobilized by the administrations of Ipriflavon or Morin. The retained amount of 85Sr in the organism of the animals decreased by about 50-70%. In the case of new-born rats the treatment decreased the whole body burden of foetuses by 20-50% of the control values. (author)