[en] The study establishes the link between the growing wind market and the emerging hydrogen market of the European Union, in a so-called 'wind-hydrogen strategy'. It considers specifically the diversion of wind electricity, as a wind power control mechanism in high wind penetration situations, for the production of renewable electrolytic hydrogen - a potentially important component of a renewable hydrogen-inclusive economy. The analysis examines the long-term competitiveness of a wind-hydrogen strategy via cost-benefit assessment. It indicates the duration and extent to which (financial) support, if any, would need to be provided in support of such a strategy, and the influence over time of certain key factors on the outcome

[en] Assessments of the radiological impact of radionuclides released into the environment generally take into account the inadvertent ingestion of radionuclides associated with soil or sediment. Such assessments often assume that gut uptake factors for radionuclides that are biologically incorporated in food are also applicable when the ingested activity is associated with soil. Studies of the availability of soil-associated radionuclides after ingestion have been mainly conducted on ruminant animals and few data exist for humans. The digestive tract of ruminants is totally different from that of a mono-gastric animal and so the availability estimated from the animal studies may not be valid in the case of man. A simple in-vitro enzymolysis procedure was therefore developed to simulate human digestion closely. The measured availability of ¹³⁷Cs, ²⁴¹Am, ²³⁹PU and ⁹⁰Sr associated with loam, sand and peat soils was about 3%, 3%, 10% and 50% respectively. (author)

[en] A collaborative team between GSE-CARS at the Advanced photon source (APS), Argonne National Laboratory, a group from the Daresbury Laboratory (SRS) and SUNY at Stony Brook was recently set up to investigate the advantages of performing in situ energy dispersive powder diffraction (EDPD) hydrothermal experiments on station 13-BM-D at the APS. The main aim of this project was to develop and further understand the techniques used for this type of research. Experiments of this nature are routinely performed at the SRS but not to 230 deg. C, as the X-ray beam can only penetrate reaction cells capable of operating above this temperature. It was hypothesized that, with the extra benefits of a third generation synchrotron source, i.e. higher X-ray energy and flux, these same experiments could be performed with reaction cells with thicker walls rated for higher temperatures. A secondary aim of the investigation was to develop an on-line injection facility for the reaction cell thus enabling the user to introduce a fluid to the hydrothermal cell held at elevated temperature and hence pressure. This work was carried out on station 13-BM-D from 15th to 25th January 1998. The experiments are performed by placing the starting mixture into a specially prepared hydrothermal cell. This cell was then heated to the desired temperature, and while the cell is at temperature the reaction mixture was monitored using energy-dispersive powder diffraction (EDPD) with one spectrum being collected every few tens of seconds. These time-resolved diffraction patterns were used to monitor the entire reaction from starting material to end product. Experiments were performed on two systems, the first being the hydrated calcium silicate system in an attempt to follow the high temperature crystallization of the mineral phases tobermorite, xonotlite and gyrolite. The second was the iron sulphide system in order to observe the formation of pyrite via its various intermediates and to utilize the newly developed injection system. Results from the hydrated calcium silicate system proved very productive with all 3 phases being successfully formed, as well as transformations from one phase to another being observed. Temperatures up to 315 deg. C were attained and the pressure was successfully contained within the reaction setup. The time-resolved diffraction data enabled the mechanism and kinetics of the reaction to be observed and many interesting and informative results were obtained (see figure a). The iron sulphide experiments proved more challenging allowing collection of only limited diffraction data, although all aspects of the hydrothermal cell worked perfectly, including the injection system. (author)

[en] Composting can be used to stabilise and reduce the volume of waste agricultural crops. The composting process results in the generation of leachates. The partitioning of radionuclides between the leachate and the solid compost is an important factor in assessing the practicability of the process as a management option. This report describes experimental work in which the partitioning of ⁹⁰Sr, ¹³⁷Cs, ²³⁹Pu and ²⁴¹Am has been determined under two contrasting sets of conditions. The results indicated that the proportion of activity transferred to the leachate depended on the experimental conditions. Temporary compost heaps such as those that a farmer might set up on open ground would benefit from being protected from precipitation, since this would reduce the amount of activity transferred to the underlying soil. For large engineered facilities where the composting process might take place in open windrows, it would be prudent to assess the need to collect leachate for subsequent treatment or disposal. (author)

[en] Glyphosate (n-phosphonomethyl glycine) is a broad spectrum herbicide widely used in lowland agriculture, forestry and improved upland pastures. Although its metal chelating properties are well established, its interaction with radionuclides remains unknown. A pot experiment was conducted to determine the effect of soil applications of glyphosate on the uptake of ²³⁹Pu and ²⁴¹Am to peas and carrots grown in loam, peat and sand soils. Soil-to-plant transfer factors were calculated for treated and untreated soils at harvest. The most marked effect was an increase in ²⁴¹Am uptake to crops grown in loam soil. Supplementary laboratory batch experiments were conducted by shaking radiolabelled soil and its associated soil solution with glyphosate. The activity concentration of ²⁴¹Am increased ten fold in the liquid phase of loam soils treated with glyphosate. It is postulated that this ²⁴¹Am desorption could have been mediated by the formation of a stable Am-glyphosate complex which was subsequently more available for crop uptake than Am alone. (author)

[en] Loam, peat and sand soils were artificially contaminated with ¹³⁷Cs, ⁹⁰Sr, ^239,240Pu and ²⁴¹Am in the winter 1983/84 as part of a five-year lysimeter study on the time dependent transfer of radionuclides to crops. Carrot, cabbage and barley crops were grown in rotation in subsequent years and after harvesting were separated into edible and unpalatable portions for radiochemical analysis. The study therefore provided an opportunity to investigate variations in the partitioning of ¹³⁷Cs, ⁹⁰Sr, ^239,240Pu and ²⁴¹Am between edible and non-palatable parts of crops when soil was the only source of activity. (Author)

[en] Variations in the transfer of radionuclides to the edible parts of crops over a 5-year period are summarized in terms of their soil-to-plant concentration ratios. Loam, peat and sand soils were artificially contaminated with ¹³⁷Cs, ⁹⁰Sr, ^239,240Pu and ²⁴¹Am in the winter of 1983/84, and placed in large containers out of doors. Carrot, cabbage and barley crops were grown in rotation in subsequent years and after harvesting were separated into edible and unpalatable portions for radiochemical analysis. Soil-to-plant concentration ratios were calculated and are discussed in terms of differences in uptake between nuclides, crops and soil types as a function of time. (Author)

[en] After a severe accident at a nuclear facility, the long term contamination of agricultural land by radiocaesium and radiostrontium may represents a significant pathway of human exposure through radionuclide uptake by food crop and animals. One potential land remedial measure for restoration of useful agricultural production is the application of soil treatments to reduce radionuclide uptake by plant roots. This may be achieved by either decreasing the absolute radionuclide concentration in soil solution or by increasing the concentration of competing ions in this phase. The effect of soil treatments such as potassium, calcium, ammonium, phosphate, organic matter and clay minerals on these two parameters is being evaluated. The evaluation makes use of the batch equilibrium approach, in which in situ conditions are replicated by using field moist soil a solid phase and its associated soil solution as a liquid phase. Five diverse soil types comprising three agricultural soils (loam, sand and peat) and two upland peats were contaminated with ¹³⁴Cs and ⁹⁰Sr in April 1993. The first set of batch equilibrium experiments was conducted six months after contamination. Several application rates were included for each treatment and these were chosen to reflect rates that might be applied in practice. Any treatment found to decrease Cs/K and Sr/Ca quotients in the soil solution compared to controls is being considered as a potentially effective countermeasure for reducing uptake of the appropriate radionuclide by plants. Soil type and treatment rate were shown to have important effects on both radionuclide and stable analogue concentrations in the solution phase. These experiments are being repeated one year after contamination of the soils to investigate changes in countermeasure combinations of treatments will also be evaluated at this time. (author)

[en] Objectives: To determine the frequency of Hepatitis C virus (HCV) infection and its genotypic distribution in a rural area of Sindh, Pakistan. Methodology: Retrospective study of patients attending the Free Liver Clinic (FLC), and investigated for detectable HCV antibodies (n=1638), and those screened for HCV infection prior to voluntary blood donation (n=804) at a teaching hospital, located in rural Sindh. All patients had HCV antibodies tested by ELISA. A total of 1022 patients, who tested 'reactive' to HCV antibodies, and who could financially afford to have HCV RNA tested by PCR, had their results analysed. A total of 200 patients also had their HCV genotyped and analysed. Results: Patients at FLC had a higher chance of being reactive for HCV antibodies, compared to voluntary blood donors (20% VS 14% - p = 0.004). HCV RNA was detectable in 904/1022 (88%) patients. Among type able genotypes, 125/166 (75%) had a single genotype, and 7 patients (4%) were infected with genotype 1, either alone (n=4) or in combination with 3a. Conclusions: One out of every five people tested in our FLC, and 14% of 'healthy' voluntary blood donors were seropositive for HCV antibodies. Genotype 1 is very rare in our region. (author)

[en] The effects of chronic alcohol feeding on biliary glutathione excretion were studied in rats pair fed diets containing either ethanol (36% of total energy) or isocaloric carbohydrate for 4-6 weeks. An exteriorized biliary-duodenal fistula was established and total glutathione (GSH) and oxidized glutathione (GSSG) were measured. A significant decrease was observed in rats fed alcohol chronically compared to their pair fed controls in the biliary excretion of GSH (55.7 +/- 37.0 vs 243.1 +/- 29.0 μg/ml bile, p < 0.025) as well as biliary GSSG (12.5 +/- 5.0 vs 49.9 +/- 8.0 μg/ml bile, p < 0.05) and in bile flow (23.1 +/- 1.6 vs 29.2 +/- 1.3 μg/min, p < 0.05). An acute dose of ethanol tended to exaggerate the decrease on biliary GSH and GSSG in the two groups of animals. The depression in biliary GSH could not be attributed to decreased GSH synthesis since S³⁵-L-methionine incorporation into hepatic and biliary GSH was unchanged or even increased after chronic ethanol feeding. 22 references, 4 figures