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International audience; The inventories of 137Cs (503 ± 34 Bq.m−2), 241Am (11.3 ± 1.2 Bq.m−2), 241Pu (33.7 ± 3.4 Bq.m−2), 238Pu (6.82 ± 0.87 Bq.m−2) and 239+240Pu (113.0 ± 5.9 Bq.m−2), sum of 239Pu (100 ± 11 Bq.m−2) and 240Pu (14.5 ± 1.7 Bq.m−2), in the Gambier archipelago (23°S) of the French Polynesia, are well higher the global fallout at this latitude, in unequal proportions for the different radionuclides. (240Pu/239Pu)AR (AR: atomic ratio) of 0.0394 ± 0.0062, and (241Pu/239Pu)AR of (2.03 ± 0.39)10−4, confirm that the overwhelmingly dominant source of these radionuclides comes from local fallout during the 1970s of the French atmospheric tests of Moruroa and Fangataufa located nearly 400 km from Gambier. The signatures of the local fallout were deduced from the excess of its inventory in 137Cs and from the mixing lines established from the signatures of the global fallout, some of the test sites and the isotopic ratios measured in Gambier. Signatures obtained are 2.0 ± 0.4 for 137Cs/239+240Pu, 0.045 ± 0.008 for 238Pu/239+240Pu, 0.031 ± 0.009 for 241Am/239+240Pu, 0.092 ± 0.027 for 241Pu/239+240Pu, 0.0163 ± 0.0049 for (240Pu/239Pu)AR, (0.78 ± 0.23)10−4 for (241Pu/239Pu)AR. The concordance of the mixing lines of the [(240Pu/239Pu)AR, (241Pu/239Pu)AR] and the linear regression of these ratios measured in the stratosphere (40°S) during the 1970s, indicates that the signatures of the close-in deposition are also those of the stratospheric injections of the French tests. The signatures of stratospheric fallout in the Southern Hemisphere were evaluated by considering that the fission energy of these injections represents 11% and that of the Northern Hemisphere represents 89% and that the isotopic ratios of stratospheric injections remained the same over the period 1970–1974. The activity ratios deducted are 21.9 ± 0.1 in 137Cs/239+240Pu, 0.11 ± 0.05 in 238Pu/239+240Pu, 1.03 ± 0.12 in 241Pu/239+240Pu and 0.35 ± 0.04 in 241Am/239+240Pu. The associated atom ratios are 0.157 ± 0.011 for (240Pu/239Pu)AR and (8.33 ± 0.48)10−4 for (241Pu/239Pu)AR. These signatures appear to be consistent with the results of the inventories at Hiva Oa, located more than 1,000 km north of both French test sites, and with those found in the Australian continent, in regions not impacted by UK-test debris. The proportions of close-in tropospheric fallout from the French tests are about 90% in Gambier. They represent a proportion in the inventories of 40% for the 137Cs, 60% for 241Am and in the range between 80 and 90% for Pu isotopes.

The inventories of

Cette note s’appuie sur des donnees de la surveillance de l’environnement des installations du cycle du combustible. Il s’agit d’evaluer l’uranium ajoute dans l’environnement terrestre par les rejets. Ainsi, nous illustrons par la mesure des isotopes de l’uranium dans les plantes terrestres les consequences d’un rejet chronique et d’un rejet incidentel d’uranium appauvri dans l’atmosphere. Cependant, cette methode analytique atteint ses limites quand les rejets des installations concernent l’uranium naturel. Distinguer l’uranium naturel provenant des rejets et l’uranium qui derive du fond radiologique devient alors delicat. C’est pourquoi, nous proposons de normaliser l’activite en uranium des plantes prelevees autour des sites nucleaires par rapport a l’activite en 232 Th, en considerant que la source de ce dernier est le fond radiologique.

The large rivers are main pathways for the delivery of suspended sediments into coastal environments, affecting the biogeochemical fluxes and the ecosystem functioning. The radionuclides from 238 U and 232 Th—series can be used to understand the dynamic processes affecting both catchment soil erosion and sediment delivery to oceans. Based on annual water discharge the Rhone River represents the largest river of the Mediterranean Sea. The Rhone valley also represents the largest concentration in nuclear power plants in Europe. A radioactive disequilibrium between particulate 226 Ra (p) and 238 U (p) was observed in the suspended sediment discharged by the Lower Rhone River (Eyrolle et al. 2012), and a fraction of particulate 234 Th was shown to derive from dissolved 238 U (d) (Zebracki et al. 2013). This extensive study has investigated the dissolved U isotopes distribution in the Lower Rhone River and its implication on particulate radionuclides disequilibrium within the decay series. The suspended sediment and filtered river waters were collected at low and high water discharges. During the 4—months of the study, two flood events generated by the Rhone southern tributaries were monitored. In river waters, the total U (d) concentration and U isotopes distribution were obtained through Q-ICP-MS measurements. The Lower Rhone River has displayed non-conservative U—behavior, and the variations in U (d) concentration between southern tributaries were related to the differences in bedrock lithology. The artificially occurring 236 U was detected in the Rhone River at low water discharges, and was attributed to the liquid releases from nuclear industries located along the river. The ( 235 U/ 238 U) (d) activity ratio (=AR) in river waters was representative of the 235 U natural abundance on Earth. The ( 226 Ra/ 238 U) (p) AR in suspended sediment has indicated a radioactive disequilibrium (average 1.3 ± 0.1). The excess of 234 Th in suspended sediment =( 234 Th xs(p) ) was apparent solely at low water discharges. The activity of 234 Th xs(p) was calculated through gamma measurements and ranged from unquantifiable to 56 ± 14 Bq kg −1 . The possibility of using 234 Th as a tracer for the suspended sediment dynamics in large Mediterranean river was then discussed.

International audience; A new protocol for the rapid quantification of actinides (U, Th, Pu, Am and Np) and 90Sr in soil samples has been developed. This protocol includes three steps (1) an alkaline fusion digestion, (2) an automated separation and (3) an on-line ICP-MS measurement. Eluted fraction containing strontium can be collected to quantify radiostrontium using off-line radiometric techniques. After an optimization of the separation protocol using a design of experiments, excellent figures of merit are achieved. These figures include high chemical recoveries (andgt;80%) for all radionuclides investigated, low quantification limits for actinides and concordance between measured activities and reference values. This protocol allows the automated treatment (sample dissolution included) of up to 10 samples in 24 h. © 2017, Akadémiai Kiadó, Budapest, Hungary.

International audience; In the present paper the activity of uranium isotopes measured in plants and aerosols taken downwind of the releases of three nuclear fuel settlements was compared between them and with the activity measured at remote sites. An enhancement of 238U activity as well as 235U/238U anomalies and 236U are noticeable in wheat, grass, tree leaves and aerosols taken at the edge of nuclear fuel settlements, which show the influence of uranium chronic releases. Further plants taken at the edge of the studied sites and a few published data acquired in the same experimental conditions show that the 238U activity in plants is influenced by the intensity of the U atmospheric releases. Assuming that 238U in plant is proportional to the intensity of the releases, we proposed empirical relationships which allow to characterize the chronic releases on the ground. Other sources of U contamination in plants such as accidental releases and “delayed source” of uranium in soil are also discussed in the light of uranium isotopes signatures. © 2017 Elsevier Ltd

Background Sudden cardiac arrest (SCA) is a major cause of deaths in Europe, but population-based data on specific etiologies, such as structural non ischemic heart disease (SNIHD) are lacking. Purpose We sought to determine the frequency, characteristics and outcomes of SCA associated with SNIHD in the general population. Methods In this prospective ongoing multicentre population-based registry, data from all SCA were analyzed. SNIHD included different non ischemic cardiomyopathies, as well as valvular, hypertensive and congenital heart diseases. Medical records were reviewed by cardiologists to identify clinical conditions underlying SCA. Results Of the 18,622 out-of-hospital cardiac arrests from May 2011 to May 2016, 3028 SCAs (16.2%) were admitted alive to hospital. Two hundred and twenty four (7.4%) SNIHD were diagnosed during hospitalization, including dilated cardiomyopathy (DCM) (44.2%), valvular heart disease (19.2%), hypertrophic cardiomyopathy (13.4%), myocarditis (6.7%), congenital heart disease (3.1%) and arrhythmogenic right ventricular dysplasia (2.7%). As compared to other causes of SCA, SNIHD patients were significantly younger (55.2 vs. 59.6 years, P Conclusion In our registry, SCA associated with SNIHD presented distinctive features compared to non-SNIHD, and overall accounted for only 7% of the overall SCA burden. Main causes were DCM and valvular heart disease. Better characterization of this population, especially the sizeable subgroup with left ventricular ejection fraction > 35% can improve sudden death risk stratification in this group.

Background Considering that most patients resuscitated from out-of-hospital sudden cardiac arrests (SCA) die in the intensive care unit (ICU), early systematic etiologic investigation may represent an important strategy towards targeted therapy and appropriate prevention to first-degree relatives at risk. Purpose We aimed to determine the extent to which SCA cases who died in the ICU were investigated. Methods In this prospective ongoing multicentre population-based registry, data from all SCA patients who died in ICU were analyzed. The extent of investigations was defined as complete either in case a combination of coronary angiography (CA), brain, chest CT scan, and trans-thoracic echocardiography (TTE) was performed, or diagnosis found after one of those. SCAs dying in the first 24 hours were excluded because of their poor hemodynamic condition for investigation. Results Of the 18,622 out-of-hospital cardiac arrests from May 2011 to May 2016, 3028 SCA (16%) were admitted alive to ICU, and 2190 (72.3%) died in ICU. After first day exclusion, 947/1417 (66.8%) fulfilled criteria for complete investigations and 470/1417 (33.2%) in the other group. In the group with incomplete investigations, CA was performed in 162 patients (34.6%), TTE in 207 (44.2%), and brain and/or chest CT in 186 (39.6%). A final diagnosis was made for 895 patients (94.5%) in the group with complete investigations: 403 (45.0%) acute CAD, 149 (16.7%) chronic CAD, 115 (12.9%) neurological causes, 80 (8.9%) structural non-ischemic heart disease, 48 (5.4%) pulmonary embolism. Overall, among all unexplained SCA who died in ICU, 434 (89.3%) had incomplete investigation. Conclusions Over a third of SCA who died in ICU did not undergo complete etiologic investigations, preventing from potential adequate familial screening. Improvement in systematic medical assessment is crucial to provide appropriate therapy and prevention to family members.

Background Considerable apprehension often surrounds the issue of sudden cardiac arrest (SCA) during physical activity, and especially SCA related to sexual activity, which has not been well studied in the community. Purpose We sought to assess the burden, characteristics and outcomes of SCA related to sexual activity compared to other physical activities. Methods In this multicentre prospective ongoing study in the general population, every case of SCA was exhaustively collected. Data from all SCA during physical activity, alive at hospital admission, were analyzed with a specific focus on cases occurring during sexual intercourse. Results Among the 3028 SCAs admitted alive out of a total of 18,622 out-of-hospital cardiac arrests from May 2011 to May 2016, 246 (8.1%) SCA (219 men, 89.0%) occurred during physical activity: 138 (56%) during sports, 91 (37%) during moderate-intensity activity and 17 (7%) during (hetero-) sexual intercourse. SCA during sexual activity were more likely to be male (100.0 vs. 88%, P = 0.22), with higher no flow (8.4 vs. 3.1 min, P Conclusion SCA during sexual intercourse is a relatively rare cause of SCA and is associated with a particularly poor outcome. The low rate of CPR in this setting may be related to the uniquely private circumstances of the arrest and could contribute to low survival rate.

The quantification of radionuclides by direct gamma-X spectrometry with energy below 100 keV requires knowledge the elementary composition of the sample or the development of a device for determining the mass attenuation coefficients. This is especially true for 129 I which is characterised by a 29.8 keV X-ray and 39.6 keV gamma ray. Experimental equipment has been developed in order to obtain this mass attenuation coefficient as a function of energy. 129 I concentrations were measured in samples of seaweed (Fucus serratus and Laminaria digitata) collected monthly over a period of one year nearby La Hague reprocessing plant in France. This paper describes the measurement methodology used to determine 129 I concentrations and variations in the two seaweeds over a one-year period. Mean mass attenuation coefficients for 129 I energies were established in order to determine the self-attenuation corrective factor for both seaweed species, regardless of the sampling date. Iodine-129 is a beta emitter (T1/2 = 1.57 × 10 7 years) with both natural and artificially produced radionuclides existing in the environment. This radionuclide will decay to emit photons of energies below 40 keV at high intensity. Direct gamma-X spectrometry is therefore well suited to quantifying this radionuclide, provided that self-attenuation corrections are applied. These corrections must not only take into account the density but also the elementary composition of the matrix seeing that the photoelectrical process becomes the dominating interaction phenomenon under 100 keV. We recently developed a corrective method based on transmission measurements (1-2) to determine these self-attenuation correction factors in relation to standard calibration sources. Temporal variations in the self-attenuation coefficient are related to variations in the elementary composition of the matrix, including variations in iodine in the case of seaweed. Our study focused on brown seaweed, more specifically Fucus serratus and Laminaria digitata, which are used as bio-indicators in environmental studies to monitor various pollutants (3-9). The specificity of such seaweed resides in their sedentary nature on the one hand and the fact that they concentrate elements that are only soluble in their surrounding environment on the other hand.

International audience; Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely 238U/232Th and 230Th/232Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and 230Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6×10-3 and 5.0×10-3ms-1, respectively. © 2014 Elsevier Ltd.

Polymers used as electrical insulation in high voltage underground power cables have excellent short term mechanical and dielectric properties. They can however be susceptible to long term deterioration due to the application of high electrical stress. There is a need to further understand the process of electrical ageing, which implies detecting and characterising the degradation. Detection is however often achieved once ageing is already significant, for example when partial discharge activity is present from a large enough microcavity. A method for early detection of electrical ageing is therefore necessary and electroluminescence (EL) is known to be such a method. This paper places emphasis on the description of a new experimental arrangement used to detect this very low level of light and to determine the spectral and spatial resolution of EL. It presents the characteristics of EL emitted in low density polyethylene (LDPE) and crosslinked polyethylene (XLPE) thin plaques in a uniform field configuration at room temperature under ac stress.