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The inventories of 137 Cs (503 ± 34 Bq.m -2 ), 241 Am (11.3 ± 1.2 Bq.m -2 ), 241 Pu (33.7 ± 3.4 Bq.m -2 ), 238 Pu (6.82 ± 0.87 Bq.m -2 ) and 239+240 Pu (113.0 ± 5.9 Bq.m -2 ), sum of 239 Pu (100 ± 11 Bq.m -2 ) and 240 Pu (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. ( 240 Pu/ 239 Pu) AR (AR: atomic ratio) of 0.0394 ± 0.0062, and ( 241 Pu/ 239 Pu) 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 137 Cs 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 137 Cs/ 239+240 Pu, 0.045 ± 0.008 for 238 Pu/ 239+240 Pu, 0.031 ± 0.009 for 241 Am/ 239+240 Pu, 0.092 ± 0.027 for 241 Pu/ 239+240 Pu, 0.0163 ± 0.0049 for ( 240 Pu/ 239 Pu) AR , (0.78 ± 0.23)10 -4 for ( 241 Pu/ 239 Pu) AR . The concordance of the mixing lines of the [( 240 Pu/ 239 Pu) AR , ( 241 Pu/ 239 Pu) 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 137 Cs/ 239+240 Pu, 0.11 ± 0.05 in 238 Pu/ 239+240 Pu, 1.03 ± 0.12 in 241 Pu/ 239+240 Pu and 0.35 ± 0.04 in 241 Am/ 239+240 Pu. The associated atom ratios are 0.157 ± 0.011 for ( 240 Pu/ 239 Pu) AR and (8.33 ± 0.48)10 -4 for ( 241 Pu/ 239 Pu) 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 137 Cs, 60% for 241 Am and in the range between 80 and 90% for Pu isotopes., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

We present modified scanning-type wavefront folding interferometers (WFIs), which allow spatial coherence measurements of non-uniformly correlated fields, where the degree of coherence is a function of two absolute spatial coordinates instead of coordinate separation only (Schell model). As an alternative to conventional prism-based WFI implementations, we introduce a scheme based on reflections by three mirrors. This setup allows us to avoid obstructions due to prism corners, and it is remarkably robust to polarization effects. Experimental results on measurement of fields that do not obey the Schell model are provided with the three-mirror WFI, and the results are compared to those obtained with a Young's interferometer realized using a digital micromirror device.

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., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

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 238 U activity as well as 235 U/ 238 U anomalies and 236 U 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 238 U activity in plants is influenced by the intensity of the U atmospheric releases. Assuming that 238 U 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., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

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 (238)U/(232)Th and (230)Th/(232)Th) 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 (230)Th-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(-3) m s(-1), respectively., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Staphylococcus aureus is a highly versatile pathogen in a large number of domestic animals, including avian species. To gain deeper insight into the epidemiology and diversity of S. aureus associated with articular disease in domestic turkeys, isolates were collected from infected foot joints of turkeys in Brittany (France). A total of 34 isolates were recovered and characterized by means of antimicrobial resistance, staphylococcal protein A typing, macrorestriction pulsed-field gel electrophoresis and micro-array analysis. Thirty isolates were identified as clonal complex (CC) 398 and methicillin-susceptible S. aureus (MSSA), one was identified as a methicillin-resistant S. aureus (MRSA) CC398 isolate, and the remaining were also MSSA and belonged to CC5, CC101, and CC121. Eleven different antimicrobial resistance patterns were detected, with most isolates resistant to penicillin and tetracycline. Based on all typing methods used, the 34 isolates could be divided into 22 different strains. Results on selected isolates, genotyped using microarrays, indicated a high homogeneity among pathogenic MSSA isolates from turkeys. Moreover, all isolates, except the unique MRSA isolate, carried specific φAvβ prophage avian-niche-specific genes, demonstrating the versatility of S. aureus to adapt to the specific ecological poultry niche.

A genital and potentially fatal form of Pasteurella multocida infection was reported on two turkey-breeding farms on which birds were vaccinated against Pasteurella multocida. Both outbreaks were linked to the use of semen from young vaccinated toms with a history of respiratory pasteurellosis followed by treatment during rearing. Typing by agar gel immunodiffusion and rapid slide agglutination of P. multocida isolated from cloacal swabs was completed by multilocus sequence typing. Restriction enzyme analysis showed that that the isolates were clonal. They belonged to sequence type (ST) 30, described in chickens, cats, and ducks. This strain differed in sequence type from the ones used in the vaccine (ST8, ST60, ST53, and ST235), which might have limited its effectiveness. No contamination of the semen (n = 30) was found, suggesting fecal contamination during semen collection.