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The disposal of highly radioactive spent nuclear fuel in deep geological media will require excavating a large number of galleries in low-permeable rocks, altering initial rock integrity at the repository site. The FE tunnel excavated in Opalinus Clay at the Mont Terri Underground Research Laboratory (Switzerland) is a unique full-scale experiment to study this process. We conducted a numerical study of the excavation of the FE tunnel in a coupled hydro-mechanical finite element framework, employing an anisotropic plasticity coupled with damage constitutive model. A second gradient of dilatancy formulation is employed to avoid spurious mesh-dependent behavior originating from the softening of the coupled damage-plasticity model. The approach is validated by comparing numerical predictions and in situ observations during and after tunnel excavation in terms of displacements, pore water pressure evolution and degradation of elasticity. Mechanical parameters are calibrated using laboratory experiments and values available in the literature. The model well reproduces the coupled hydro-mechanical processes induced by excavation, giving a good agreement between numerical predictions and experimental in situ monitoring data. Furthermore, the evolution of the excavation damaged zone is correctly predicted. Thus, this modeling approach is suitable for the purpose of simulating tunnel excavation in low-permeable anisotropic quasi-brittle shales. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the inter-laboratory reproducibility for atypical glandular cells (AGC) (The Bethesda System (TBS) 2001) of the laboratories involved in the screening programmes in Italy. Methods: A set of 35 selected slides were circulated among 167 laboratories involved in local population-based cervical screening programmes. Each laboratory provided one single diagnosis per smear. The smears were read blind to the original diagnosis and to the diagnoses provided by other laboratories. A ‘majority’ diagnosis was defined for each case and assumed as the reference standard. The diagnosis provided from each laboratory was compared with the majority diagnosis. Results: According to the majority report the 35 slides in the set were classified as negative in nine cases, AGC in eight, adenocarcinoma in eight, and squamous lesion or squamous + glandular lesion in 10. The crude agreement between all pairs of laboratories was 49.43%. K-values were 0.46, 0.21, 0.34, 0.36 and 0.32 for negative, AGC/AIS (adenocarcinoma in situ of endocervix), AdenoCa, Sq/Sq + Gl and all reporting categories respectively. Concordance according to overall K was moderate to substantial in 77% of the participating laboratories. Conclusions: The present study shows that the AGC category is not easily reproducible. The data confirmed the importance, in a screening scenario, of AGC/AIS diagnoses, but also presented difficulties in differentiating between the two diagnoses. In addition to the results obtained from the circulation of the slides, laboratories which had annually a low number of cervical smears were able to gain experience focused on particular morphological pictures. [ABSTRACT FROM AUTHOR]

The study was aimed at assessing interlaboratory reproducibility in the reporting of cervical smears in the atypical squamous cells of undetermined significance (ASCUS) category. A set of 50 selected slides circulated among 89 laboratories, currently involved in population-based screening programmes for cervical cancer, which provided a diagnostic report according to four main reporting categories based on the 1991 Bethesda system. Interlaboratory agreement was determined according to kappa (K) statistics: overall and weighted K values were determined for each laboratory and for single reporting categories. The results showed a very low reproducibility for the ASCUS category. This finding supports the Bethesda system 1991 recommendation to limit the use of this reporting category and suggests that the clinical response to ASCUS repons should be decided locally, based on the observed positive predictive value for cervical intraepithelial neoplasia 2 or more severe lesions. [ABSTRACT FROM AUTHOR]

The study objective was assessing whether circulation of smears and discussion of those with differing interpretation can increase reproducibility between laboratories. The study included: the blind interpretation of a first set of 194 smears among seven laboratories, the discussion of smears with discrepant diagnoses during the previous phase and the blind interpretation of a second set of smears of same size and characteristics. After discussions, the overall weighted kappa increased in five laboratories (substantially in three: +50%, +27% and +20%). However, no change was observed in one laboratory and a slight decrease (-4%) in another. The latter interpreted the second set of smears at a longer time interval from discussions. Agreement improved for all diagnostic classes except low grade intraepithelial neoplasia (LSIL). Overall, the intervention increased diagnostic agreement, but its effect varied with laboratory and by diagnostic class and could be transient. Continued programmes of smear exchange and discussion appear to be advisable. [ABSTRACT FROM AUTHOR]