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Strain-controlled fully reversed fatigue testing, or strain-life testing, provides critical information on material lifetime and damage response. Strain-life data in hydrogen gas environments is missing in the literature and could provide valuable insights into hydrogen effects on the mechanical response of metals such as steel. We adapted existing hydrogen-gas-environment mechanical-testing equipment, which had been designed only for tensile loads, to accommodate the large compressive loads needed to perform strain-life testing. The considerations of these adaptations are discussed. Successful strain-life testing data were acquired from a 4130 pressure vessel steel.

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The purpose of this publication is to provide guidance on radiological protection in industries involving naturally occurring radioactive material (NORM). These industries may give rise to multiple hazards and the radiological hazard is not necessarily dominant. The industries are diverse and may involve exposure of people and the environment where protective actions need to be considered. In some cases, there is a potential for significant routine exposure of workers and members of the public if suitable control measures are not considered. Releases of large volumes of NORM may also result in detrimental effects on the environment from radiological and non-radiological constituents. However, NORM industries present no real prospect of a radiological emergency leading to tissue reactions or immediate danger for life. Radiological protection in industries involving NORM can be appropriately addressed on the basis of the principles of justification of the actions taken and optimisation of protection using reference levels. An integrated and graded approach is recommended for the protection of workers, the public, and the environment, where consideration of non-radiological hazards is integrated with radiological hazards, and the approach to protection is optimised (graded) so that the use of various radiological protection programme elements is consistent with the hazards while not imposing unnecessary burdens. For workers, the approach starts with characterisation of the exposure situation, and integration, as necessary, of specific radiological protective actions to complement the protection strategy already in place or planned to manage other workplace hazards. According to the characteristics of the exposure situation and the magnitude of the hazards, a relevant reference level should be selected and appropriate collective or individual protective actions taken. Exposure to radon is also treated using a graded approach, based first on application of typical radon prevention and mitigation techniques, as described in Publication 126. A similar approach should be implemented for public exposure through the control of discharges, wastes, and residues after characterisation of the situation. If the protection of non-human species is warranted, it should be dealt with after an assessment of radiological exposure appropriate for the circumstances, taking into account all hazards and impacts. This should include identification of exposed organisms in the environment, and use relevant derived consideration reference levels to inform decisions on options for control of exposure.

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Strain-life testing of a 4130 pressure vessel steel was conducted in hydrogen gas through the careful adaptation of an existing hydrogen-gas mechanical-testing apparatus. The strain-life mechanical results reveal that hydrogen has a significant effect on the strain-life, and impacts both the elastic and plastic responses of the material. Microscopy analysis shows a distinct difference in the microstructural development of the material after cyclic loading in air compared to after loading in hydrogen gas. These experimental results will inform coupled damage and deformation modeling.

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Located in the south-western part of Brazil, the state of Rio de Janeiro is geotectonically contained within a complex structural province that resulted in the amalgamation of the Western Gondwana Paleocontinent. To undertake an extensive radiological characterization of this complex geological province and investigate the influence of bedrock, soil type and soil chemical-physical characteristics on natural radionuclide levels in soils, 259 surface soil samples were collected that encompassed the main soil types and geological formations throughout the state. Gamma spectrometry analysis of the samples resulted in median values of 114 Bq.kg-1for 40K, 32 Bq.kg-1 for 226Ra and 74 Bq.kg-1 for 228Ra. The median value for 226Ra was similar to the world median value for soils, the 40K value was well below the worldwide value, and that for 228Ra exceeded the world median value. The intense weathering caused by the high rainfall rates and high temperatures may be responsible for the low levels of 40K in the soils, of which the strongly acidic and clayey soils are markedly K-depleted. A soil from a high-grade metamorphic rock (granulite) presented the lowest 226Ra (18 Bq.kg-1) content, whereas the highest levels for 226Ra (92 Bq.kg-1) and 228Ra (139 Bq.kg-1) were observed in a young soil enriched in primary minerals (Leptsol). A lowland soil (Gleysol) showed the highest median of 40K (301 Bq.kg-1). Strongly acidic soils tended to present high amounts of 226Ra, and sandy soils tended to contain low levels of 228Ra. The external radiation dose indicates that the state has a background radiation level within the natural range.

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In the aftermath of the devastating Haitian earthquake, we became the primary relief service for a large group of severely injured earthquake victims. Finding ourselves virtually isolated with extremely limited facilities and a group of critically injured patients whose needs vastly outstripped the available resources we employed a disaster triage system to organize their clinical care. This report describes the specific injury profile of this group of patients, their clinical course, and the management philosophy that we employed. It provides useful lessons for similar situations in the future.

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Vegetables grown with phosphate fertilizer (conventional management), with bovine manure fertilization (organic management) and in a mineral nutrient solution (hydroponic) were analyzed and the concentrations of (238)U, (226)Ra and (228)Ra in lettuce, carrots, and beans were compared. Lettuce from hydroponic farming system showed the lowest concentration of radionuclides 0.51 for (226)Ra, 0.55 for (228)Ra and 0.24 for (238)U (Bq kg(-1) dry). Vegetables from organically and conventionally grown farming systems showed no differences in the concentration of radium and uranium. Relationships between uranium content in plants and exchangeable Ca and Mg in soil were found, whereas Ra in vegetables was inversely correlated to the cation exchange capacity of soil, leading to the assumption that by supplying carbonate and cations to soil, liming may cause an increase of U and a decrease of radium uptake by plants. The soil to plant transfer varied from 10(-4) to 10(-2) for (238)U and from 10(-2) to 10(-1) for (228)Ra.

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The objective of the Environmental Radiological Monitoring Control programme carried out by the Institute of Radiation Protection and Dosimetry (IRD) in Brazil is to verify the licensee's compliance with the requirements for environmental monitoring of Brazilian facilities. The Joint Sampling Programme (JSP) is just one part of the control programme. In order to verify that the data reported by the licensees is representative and legitimate, this programme verifies sampling procedures, accuracy and precision of the data and the changes in the environmental conditions. This paper discusses the main findings of this programme that allowed IRD to optimize its available resources to control the monitoring of the eight facilities in Brazil.

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Concentrations of Al, Cd, Cr, Cu, Mn, Ni, Pb, U and Zn were determined in vegetables (leafy vegetables, fruit, root, grain and cereal), derived products (sugar, coffee, manioc flour, wheat flour, corn flour, and pasta) and animal products (meat, fish, milk) most frequently consumed by adult inhabitants of Rio de Janeiro city. A total of 90 samples were analyzed using inductively coupled plasma mass spectrometry (ICPMS) as the principal method following sample dissolution by dry and wet ashing. Generally, highest contributions for the intake of micronutrients (Cu, Mn, Ni and Zn) arise from bean, rice and wheat flour consumption. Meat, cow milk and the flours, wheat and manioc, are major sources of Al, Cd, Pb and U intake. The daily intake of nine elements via foodstuffs was estimated as: 3.4x10(-4) mg of U, 1.8x10(-3) mg of Cd, 2.8x10(-2) mg of Pb, 2.3x10(-2) mg of Cr, 8.9x10(-2) mg of Ni, 1.12 mg of Cu, 2.5 mg of Mn, 3.5 mg of Al and 4.8 mg of Zn. The intake of toxic elements ranged between 2.7% (Cd) and 30% (U) of the provisional tolerable daily intake and reference dose values indicating that food consumption is, at present, no critical factor for the uptake of these toxic metals, in the population studied here. Concerning micronutrients, the recommended values of daily intake of Cu and Mn are conveniently supplied by the diet; however, for Cr and Zn they are lower than the recommend daily allowance. Due to high metal concentrations and consumption rates, black bean is the foodstuff that provided the highest ingestion rates of Cu, Mn, Ni and Zn (36-60% of the reference dose), being therefore a very important source of micronutrient supply.

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Ground water from Região dos Lagos, a coastal area of Rio de Janeiro state, was analysed for (226)Ra, (228)Ra, (222)Rn, (238)U, major ion concentrations, and physico-chemical parameters were also measured. Concentrations values ranged from <0.002 to 0.492 Bq l(-1) for (226)Ra, from <0.01 to 1.50 Bq l(-1) for (228)Ra and from < 1.0 x 10(-4) to 8.0 x 10(-2) Bq l(-1) for (238)U. Detectable (222)Rn concentrations (>3 Bq l(-1)) were found only in two samples. The spatial distribution of Ra concentration delineated one distinct area and some hot spots with high Ra concentration. Low pH value is the most important water parameter linked to high radium concentration. This is probably related to limited adsorption of radium on soil ferric oxides and hydroxides at low pH range. There was a significant correlation between uranium concentrations and electrical conductivity values, and also between uranium concentrations and concentrations of Ca, Mg, Na, K, and Cl, indicating sea water impact. Uranium concentrations were lower than maximum contaminant level for drinking water, whereas 17 out of the 88 ground water samples had levels of radium that exceeded the maximum contaminant level for tap water. The total annual effective dose for adult due to the water consumption reaches values up to 0.8 mSv.

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The concentrations of the naturally occurring radionuclides 232Th, 238U, 210Pb, 226Ra and 238Ra were determined in the vegetables (leafy vegetables, fruit, root, bean and rice) and derived products (sugar, coffee, manioc flour, wheat flour, corn flour and pasta) consumed most by the adult inhabitants of Rio de Janeiro City. A total of 88 samples from 26 different vegetables and derived products were analyzed. The highest contribution to radionuclide intake arises from bean, wheat flour, manioc flour, carrot, rice, tomato and potato consumption. The estimated daily intakes due to the consumption of vegetables and derived products are 1.9 mBq of 232Th (0.47 microg), 2.0 mBq of 238U (0.17 microg), 19 mBq of 236Ra, 26 mBq of 210Pb and 47 mBq of 228Ra. The estimated annual effective dose due to the ingestion of vegetables and their derived products with the long-lived natural radionuclides is 14.5 microSv. Taking into account literature data for water and milk from Rio de Janeiro the dose value increases to 29 microSv, with vegetables and derived products responsible for 50% of the dose and water for 48%. 210Pb (62%) and 228Ra (24%) were found to be the main sources for internal irradiation.

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Unexpected high 228Ra concentrations, up to 2 Bq 1(-1), were found in waters of a coastal lagoon close to a monazite sand separation plant. Due to their use as process waters in this plant, the initial supposition was a contamination related to its operation. However, it was concluded that these abnormal radium concentrations had a natural origin, springs at the lagoon head area with high 228Ra and 226Ra concentrations. The strong relationship among radium and light rare-earth elements (LREEs), the observed 228Ra/226Ra activity ratio and the rare-earth element pattern in the spring waters suggested that monazite is the main source of nuclides for water, indicating the disturbance of monazite chemical stability by the combined effects of low pH and high salinity. Both factors combined allow relatively low mobility of thorium, but, on the other hand, a relatively high mobility of radium and LREEs.

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The role played by serotonin (5-HT) in the regulation of bronchomotor tone has up to now been a much debated question, although there is good evidence that it induces intense bronchoconstriction after inhalation in asthmatic patients. Serotonin has been found to contract the tracheobronchial smooth muscle of different animals. Some data suggest that tracheobronchial contraction due to serotonin is mediated by its interaction with the S2-receptor. The blockade of this receptor by ketanserin, a serotoninergic antagonist which primarily binds to S2-serotoninergic receptors, produces bronchodilation. The respiratory effects of intravenously administered ketanserin (10 mg) or placebo were compared in a double-blind crossover study in 14 patients with chronic obstruction of the airways. The forced expiratory volume in one second (FEV1) and the instantaneous forced expiratory flow after 50 percent of the forced vital capacity has been exhaled (FEF50%) did not change after placebo, but they increased significantly after administration of ketanserin. The results suggest that in patients with chronic obstructive pulmonary disease, serotonin may play a role in the development of obstruction of the airways, even if the mechanism remains undefined.

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We describe a new method of preparing thin sources for the determination of uranium isotopes by alpha-spectrometry. The sources are produced by extracting the uranium isotopes from 1 M HNO3-4M Al(NO3)3 aqueous solution with polymeric membranes containing trioctylphosphine oxide (TOPO). We demonstrated that the sources are comparable to those obtained by electrochemical procedures using platinum or stainless-steel cathodes.

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