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A key component of the site comparison planned for the deep geological disposal of spent fuel and high-level waste (SF/HLW) in Switzerland is the assessment of the evolution of repository-induced perturbations in the repository nearfield associated with thermal effects from heat production due to radioactive decay of radionuclides, as well as gas pressures developing in the backfilled underground structures from the anaerobic corrosion of the steel waste canisters and tunnel support materials. The assessment of such effects is integrated in the site comparison through safety indicators used to evaluate repository performance. In this context, probabilistic assessments need to integrate the uncertainty of the entire ensemble of input parameters, and estimate the propagation to these indicators in a reliable and computationally efficient manner. This paper presents the development of a methodology for an indicator-based assessment of heat- and gas-induced effects in a SF/HLW repository in Opalinus Clay integrating a probabilistic treatment of parametric uncertainty. The workflow is demonstrated using preliminary data, repository configurations and indicators. Complementary simulations are presented to demonstrate the feedback to the optimization of repository design in order to mitigate repository-induced effects that can potentially compromise the safety function of the engineered and natural barriers.

Stratigraphic sequences in boreholes are commonly estimated by interpreting combinations of well logs. The interpretation is generally tedious and is made some time after log completion, which often leads to a loss of valuable first-hand information gathered on-site. This may lead to delayed or potentially poor on-site decisions. To make things worse, the standard interpretation of well logs is, at least to a certain degree, subjective and based on the manipulation of data, which may be difficult to trace in the long term. Small changes in lithology are often disregarded and alternating thin layers presenting different lithologies are often combined in one single (notably thicker) stratigraphic unit. Therefore an automatic parameter-based and thus traceable and objective quick look at the lithology immediately after log completion represents both a valuable tool to help with on-site decisions and a solid, mathematically based starting point for further physically based interpretations carried out by log analysts. We present a workflow for the interpretation of well logs defined as an optimization problem. The workflow is applied to the characterization of metre- to decametre-scale stratigraphic units along 13 boreholes in northern Switzerland (one-dimensional resolution) and to millimetre-scale features over a wall at the Mont Terri underground rock laboratory in Switzerland (two-dimensional resolution). The results show that: (1) the workflow accurately maps lithological changes; (2) the interaction with the analyst is minimized, which reduces the subjectivity of the interpretation; and (3) outputs are available for on-site decisions.

The excavation damaged zone (EDZ) around the backfilled tunnels of a geological repository represents a possible release path for radionuclides, corrosion and degradation gases that needs to be adequately addressed by safety assessment (SA) modelling tools. The hydromechanical phenomena associated with the creation and temporal evolution of the EDZ are of high complexity, precluding detailed representations of the EDZ in conventional SA. Thus, simplified EDZ models mimicking the safety-relevant features of the EDZ are required. In this context, a heuristic modelling approach has been developed to represent the creation and evolution of the EDZ in an abstracted and simplified manner. The key features addressed are the stochastic character of the excavation-induced fracture network and the self-sealing processes associated with the re-saturation after backfilling of the tunnels. The approach has been applied to a range of generic repository settings to investigate the impact of repository depth and in situconditions on the hydraulic significance of the EDZ after repository closure. The model has been benchmarked with a dataset from a self-sealing experiment at the Mont Terri underground rock laboratory (URL), demonstrating the ability of the approach to mimic the evolution of the hydraulic significance of the EDZ during the re-saturation phase.

To investigate gas-migration processes in saturated low-permeability argillaceous rocks, gas-injection tests under different injection pressures were carried out at different scales: on core samples at the laboratory scale; in the packed-off section of boreholes at the borehole scale (HG-B); and in the sealed microtunnel at the tunnel scale (HG-A) – a 1:2 scale experiment at the Mont Terri Rock Laboratory, Switzerland. All three tests at the Mont Terri Rock Laboratory involved Opalinus Clay. A fully coupled hydromechanical model has been developed that takes account of elastic and plastic anisotropies, anisotropic two-phase flow based on the van Genuchten function, and permeability changes when evaluating the experimental data. Two different flow regimes were studied: two-phase flow under low gas-injection pressure and dilatancy-controlled gas flow under high gas-injection pressure above the confining pressure in the laboratory experiment or the minimal principal stress in situ. When dealing with the dilatancy-controlled gas-flow regime, special consideration was made by applying two permeability approaches in which (i) the permeability change was pore-gas-pressure dependent and (ii) where the permeability change was deformation dependent.Using the parameter values determined by laboratory data, the in situborehole tests obtained under well-defined hydromechanical conditions could be analysed accordingly. The gas-flow regime in large-scale experiments, as in the case of HG-A, is mainly governed by experimental circumstances: in this case, the excavation-induced fractures around an opening with a permeability four order of magnitude higher than that in the undisturbed rock mass.

This study presents the first step of a research project that aims at using a three-dimensional (3D) hybrid finite-discrete element method (FDEM) to investigate the development of an excavation damaged zone (EDZ) around tunnels in a clay shale formation known as Opalinus Clay. The 3D FDEM was first calibrated against standard laboratory experiments, including Brazilian disc test and uniaxial compression test. The effect of increasing confining pressure on the mechanical response and fracture propagation of the rock was quantified under triaxial compression tests. Polyaxial (or true triaxial) simulations highlighted the effect of the intermediate principal stress (σ2) on fracture directions in the model: as the intermediate principal stress increased, fractures tended to align in the direction parallel to the plane defined by the major and intermediate principal stresses. The peak strength was also shown to vary with changing σ2.

For the characterization of gas migration through a low-permeability clay host rock for deep underground repositories, a comprehensive understanding of the relevant phenomena of gas and fluid flow through low-permeability clay is required. The National Cooperative for the Disposal of Radioactive Waste (Nagra) in Switzerland has developed a comprehensive programme to characterize gas flow in low-permeability Opalinus Clay through laboratory tests and detailed numerical analyses for developing appropriate constitutive models.Laboratory tests were performed on cores by two different laboratories, the Laboratory for Soil Mechanics at EPFL and the Department of Geotechnical Engineering and Geosciences at UPC. Loading tests were performed by both laboratories to study rock compressibility at different stress levels and water permeability dependence on void ratio. The water retention behaviour demonstrated by EPFL and UPC produced comparable results. Water permeability tests and fast controlled-volume air injection experiments were performed in a triaxial cell under isotropic stress conditions on two samples with flow parallel and normal to the bedding planes. A confining stress of 15 MPa was applied during gas testing, corresponding to a lithostatic pressure at a depth of c.600 m below ground.For detailed analyses, the two-phase flow code TOUGH2 (Pruess et al.1999) was used. This considers fluid flow in both liquid and gas phases under the influence of pressure, viscous and gravity forces, according to Darcy's law. The standard analyses could not reproduce the measured pressure responses well, and the calibrated hydraulic and two-phase parameters were not consistent with the preceding water test and laboratory analyses. Implementing the non-linear behaviour in terms of the observed relationship between changes in void ratio and associated changes in permeability under different stress conditions significantly improved the simulated results, resulting in a conceptual model that well reproduced the observed injection pressure and outflow responses for both tests, parallel and normal to bedding, using a consistent parameter set.

Hintergrund:Bislang liegen in Deutschland keine Befunde über die krankheitsbedingten Kosten von Patienten mit einer Borderline Persönlichkeitsstörung (BPS) aus der gesellschaftlichen Perspektive vor. Fragestellung:Wie hoch sind die jährlichen Krankheitskosten pro BPS-Patient? In welchen Bereichen entstehen die höchsten Kosten? Methodik:Auf der Grundlage aktueller gesundheitsökonomischer Empfehlungen wurden die krankheitsbedingten Kosten von N  55 BPS-Patienten in Berlin für den Zeitraum von 12 Monaten vor Beginn einer ambulanten Psychotherapie aus der gesellschaftlichen Perspektive mit einem Interview erhoben und berechnet. Ergebnisse:Die Krankheitskosten in den 12 Monaten vor der Therapie betrugen insgesamt € 26.882 (SD  € 32.275) pro BPS-Patient. € 17.976 (SD  € 23.867) davon waren direkte Kosten, € 8.906 (SD  € 15.518) wurden für indirekte Kosten berechnet. Die höchsten Kosten entstanden durch stationäre und teilstationäre Aufenthalte (M  € 13.121; SD  € 19.808) sowie durch krankheitsbedingte Erwerbsunfähigkeit (M  € 7.020; SD  € 15.099). Schlussfolgerungen:Die BPS geht mit hohen gesellschaftlichen Kosten einher, die weitaus höher sind als die durch viele andere psychische und somatische Erkrankungen bedingten Kosten.

Prevention, diagnosis and treatment of chronic degenerative diseases require the consideration of multiple factors and non-linear stochastic relations between these factors and their potential health impacts. This calls for a strong emphasis on the genetic, metabolic, behavioral and environmental characteristics of the individual. Thus, a one-fits-all medicine seems to be inappropriate for an aging society with a high burden of chronic degenerative diseases. ‘Individualized Medicine’ (IM) is a concept that was developed to respond to this new epidemiological paradigm. It has the potential to change the relationship between doctors and patients, to alter the rules, institutions and regulations of the health care sector and even to influence societal values. However, there are major barriers preventing the key stakeholders from adopting this new approach to medicine. This paper analyses these barriers and whether IM is due to become a macro innovation. It concludes that IM is still in an early stage of the development and adoption process and that it must mature in a niche before it can become the new standard solution for the health-care system.

Background and Objective: Adverse drug reactions (ADR) are appreciably harmful or unpleasant effects, resulting from an intervention related to the use of a medicinal product, with a high burden for patients and considerable economic consequences. Comprehensive pharmacoeconomic evaluations of ADR are quite rare in Germany. It is the aim of this study to determine the hospital costs of gastrointestinal bleeding effects among users of phenprocoumon. Furthermore, based on calculations of the costs of genotyping and of new drugs like dabigatran, and also on information about patient self-management (PSM), options for reducing the financial burden are investigated.

Abstract: Background: Effective health care provision benefits from the support of measurement techniques. Contrary to the situation in industrialised countries efficiency analyses in the health care sector in Africa are a very recent phenomenon. Hardly any of the existing studies was conducted at the level of primary care. Aim: The purpose of this study was twofold: (1) to evaluate the relative efficiency of health centres in rural Burkina Faso and (2) to investigate reasons for inefficient performance. Methods: Data Envelopment Analysis (DEA) was applied. To account for the situation in that country, the output-oriented approach was used in connection with different returns to scale assumptions. To identify the spatial effect of the catchment area on efficiency the Tobit model was applied. Results: According to constant returns to scale, 14 health centres were relatively efficient. The DEA projections suggest that the inefficient units were too big to be efficient. Tobit regression showed that the relatively efficient health centres are located close to villages in their catchment area. Conclusions: For ethical reasons it is not appropriate to try to improve the efficiency of health centres by closing some of them. Their efficiency can be improved and lives can be saved if access to health centres is enhanced.

AbstractThe Gas Migration Test (GMT) at the Grimsel Test Site underground laboratory in central Switzerland was designed to investigate gas migration through an engineered barrier system (EBS). The EBS consists of a concrete silo embedded in a sand/bentonite buffer emplaced in a silo cavern that intersects a shear zone in the surrounding granite host rock. The experiment was performed in a series of stages: (a) excavation of the access drift and silo cavern, (b) construction and instrumentation, (c) saturation of the EBS, (d) water tests, (e) long-term gas injection at different rates, (f) postgas water testing, (g) gas injection with a “cocktail” of gas tracers, and (h) depressurization and dismantling. A numerical model was developed for the design and analysis of the different stages and to describe the relevant phenomena associated with gas migration from a potential repository for transuranic waste.A numerical model of the GMT was implemented with the two-phase-flow code TOUGH2, representing the GMT silo with a multilayered radially symmetric mesh and the surrounding water-conducting granite shear zone with a two-dimensional vertical feature. The different stages of the experiment were simulated in sequence using the results of the previous stage as initial conditions for the subsequent stage. Two-phase-flow parameters for the EBS were derived from laboratory experiments on core samples of the different materials that comprise the EBS, while hydraulic properties of the sand/bentonite and of relevant interface zones were calibrated to the pressure responses in the silo and selected piezometers in the sand/bentonite. The results of the numerical modeling of the GMT experiment show that the main features and processes of the different stages of the experiment could be reasonably well reproduced. Following the initial calibration of effective properties from the water test response during stage 4, property changes during the subsequent test phase were calibrated as stress-or pressure-dependent permeability changes. During the gas injection phases, the pressure-dependent permeability change could be related to the minimum effective stresses along interfaces. The inferred coupled hydromechanical phenomena were implemented using pressure-dependent permeability relationships on interfaces at the top of the silo and between the sand/bentonite and the granite host rock. During the recovery sequence following the first injection gas phase, the calibrated decrease in permeability of the sand/bentonite above the silo was related to the pressure decline in the upper cavern, but there was no apparent stress change. However, the calibrated permeability reduction in the sand/bentonite was in the range of values measured during the EBS excavation. In addition, time-dependent permeability relationships were calibrated for the tunnel seal to account for the gradual decrease in water inflow from the upper cavern into the access tunnel and the drift.