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In the context of radioactive waste disposal, an underground research laboratory (URL) is a facility in which experiments are conducted to demonstrate the feasibility of constructing and operating a radioactive waste disposal facility within a geological formation. The Meuse/Haute-Marne URL is a site-specific facility planned to study the feasibility of a radioactive waste disposal in the Callovo-Oxfordian (COx) claystone. The thermo-hydro-mechanical (THM) behaviour of the host rock is significant for the design of the underground nuclear waste disposal facility and for its long-term safety. The French National Radioactive Waste Management Agency (Andra) has begun a research programme aiming to demonstrate the relevancy of the French high-level waste (HLW) concept. This paper presents the programme implemented from small-scale (small diameter) boreholes to full-scale demonstration experiments to study the THM effects of the thermal transient on the COx claystone and the strategy implemented in this new programme to demonstrate and optimise current disposal facility components for HLW. It shows that the French high-level waste concept is feasible and working in the COx claystone. It also exhibits that, as for other plastic clay or claystone, heating-induced pore pressure increases and that the THM behaviour is anisotropic.

The Full-Scale Demonstration Of Plugs And Seals (DOPAS) Project is a European Commission programme of work jointly funded by the Euratom Seventh Framework Programme and European nuclear waste management organizations (WMOs). The DOPAS Project aims to improve the industrial feasibility of plugs and seals, the measurement of their characteristics, the control of their behaviour over time in repository conditions, and their hydraulic performance with respect to safety objectives.Within the project, an approach has been developed and applied to assess the compliance of two of the full-scale experiments to their design bases. The approach involves a review of each requirement in the design basis and the strategy used to demonstrate compliance of the experiment with that requirement. Feedback in the form of proposed updates to the design statements is captured by this approach. Learning points on plugs and seals from the compliance assessment are also noted for consideration in the DOPAS Project outcomes. This developed compliance and assessment approach can be employed as part of, or in conjunction with, other more generic approaches used by WMOs, including monitoring, full-scale testing and the documentation of construction procedures.

The research and development work presented in this paper was initialized by Andra in 2007. The work necessary for manufacturing and testing a full scale demonstrator is presently implemented. The case story is twofold.

After establishing nonstandard results about large deviations of Pearson statistic this paper defines the nonstandard test based on Vof the nonstandard null hypothesis: (where are standard positive numbers with ). To get a coherent test the size αmust be an infinitesimal number and depending on wether is infinitesimal or not we get different rejection criteria. We calculate risks of the first and second kinds (external probabilities) and compare this test with the nonstandard likelihood ratio test.

Various 5-alkyl-6-aza-5,6-dihydrouridines and 6-(β-D-ribopyranosyl)-5-alkyl-6-aza-5,6-dihydrouracils have been synthesized. A new regioselective method is described for coupling triazinic bases to the sugar unit. Different epimers were isolated. Antiretroviral activity against Visna virus was evaluated.

Piperazinone nucleosides can be formed by N-glycosylation with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose of either piperazin-2-ones or pyrazin-2-ones followed by reduction of the heterocycle with rhodium on alumina. All the prepared compounds were tested for their activity against the Visna virus, but did not show significant antiviral activity.

To investigate the effects of heavy metals on susceptibility of fish to Listeriosis, normal zebrafish,Brachydanio rerio(Hamilton–Buchanan), were exposed to varying concentrations of zinc (0.05, 0.15, and 0.25 mg/liter) and copper (0.05, 0.10, and 0.15 mg/liter). During copper exposure, this heavy metal did not accumulate in zebrafish kidney. Unlike copper, a small amount of zinc accumulated in kidneys of fish exposed at 0.25 mg/liter. To estimate the effects of this heavy metal on listerial infection, the mortality of fish and the number of viable bacteria in fish kidney were determined at various times (1, 4, 7, and 10 days) after ip challenge withListeria monocytogenes(strain 31386, serotype 4b). The results indicate that the number of colony-forming units in zinc-exposed fish decreased at 4, 7, and 10 days after challenge with 0.2 × LD50of viable bacteria. In contrast, copper-exposed fish indicated both decreases and increases in the number of colony-forming units depending on the concentration ofL. monocytogenesused.

Various 5-alkyl-6-aza-5,6-dihydrouridine were synthesized from the corresponding triazinic heterocycles and acetylated ribose. These nucleosides were tested for inhibitory activity on lentivirus Visna-Maedi.

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We summarize the pathogenesis of animallentiviruses (visna-maedi virus, caprine arthritis and encephalitis virus, and equine infectious anemia virus), which have raised considerable interest since the discovery of human lentiviruses. The human lentiviruses possess structural, genetic, and clinical properties similar to those of animallentiviruses. Wedescribe the different mechanisms of and the principal work on reverse transcriptase inhibitors of animallentiviruses, such as HPA-23, phosphonoformate, or 2′,3′-dideoxynucleosides. Animal viruses of this family may serve as models for infection with human Jentiviruses such as human immunodeficiency virus, the etiologic agent of AIDS.