Detection and characterization of hydraulically active fractures in a carbonate aquifer: results from self-potential, temperature and fluid electrical conductivity logging in the Combioula hydrothermal system in the southwestern Swiss Alps

A geophysical and geochemical study has been conducted in a fractured carbonate aquifer located at Combioula in the southwestern Swiss Alps with the objective to detect and characterize hydraulically active fractures along a 260-m-deep borehole. Hydrochemical analyses, borehole diameter, temperature and fluid electrical conductivity logging data were integrated in order to relate electrokinetic self-potential signals to groundwater flow inside the fracture network. The results show a generally good, albeit locally variable correlation of variations of the self-potential signals with variations in temperature, fluid electrical conductivity and borehole diameter. Together with the hydrochemical evidence, which was found to be critical for the interpretation of the self-potential data, these measurements not only made it possible to detect the hydraulically active fractures but also to characterize them as zones of fluid gain or fluid loss. The results complement the available information from the corresponding litholog and illustrate the potential of electrokinetic self-potential signals in conjunction with temperature, fluid electrical conductivity and hydrochemical analyses for the characterization of fractured aquifers, and thus may offer a perspective for an effective quantitative characterization of this increasingly important class of aquifers and geothermal reservoir

Réadaptation préopératoire avant arthroplastie du membre inférieur : connaissances et perspectives [Preoperative rehabilitation before lower limb arthroplasty : Knowledge and perspectives]

The shortening of hospital stays implies rethinking the pre- and post-operative management of lower limb arthroplasty. Optimal preparation of the patient and anticipation of the postoperative process are necessary to limit the length of stay and ensure quality, safety and patient satisfaction. This article summarises what is known about preoperative information, education and rehabilitation for primary care physicians. Physical rehabilitation is not recommended in isolation. However, patient-centred information and education is recommended for those at risk of complicated postoperative outcomes. Interdisciplinary collaboration is needed to coordinate the whole process effectively in a context of shortened lengths of stay

Assessing fracture occurrence using "weighted fracturing density": a step towards estimating rock instability hazard

International audienceBased on the assumption that major class of rock instabilities are created by discontinuities, a method is proposed to estimate the fracture density by means of a digital elevation model (DEM). By using the mean orientation, the mean spacing and the mean trace length of discontinuity sets potentially involved in slope instabilities and a DEM, it is possible to calculate the mean number of discontinuities of a given set per cell of the DEM. This would allow for an estimation of the probability of the presence of at least one discontinuity in a given area or simply in a topographic cell of the DEM. This analysis highlights sites potentially affected by rockslides within a region. Depending on the available data, the mean number can be calculated either by area, or along a line parallel to the mean apparent spacing. The effective use of the probability of occurrence is dependent on the size of the discontinuities because short and closely spaced discontinuities will have a 100% probability of occurrence in each favorable location. The a posteriori prediction of a recent rockslide is discussed as an example

Rééducation après prothèses totales de l’épaule anatomique et inversée [Update on the rehabilitation following anatomic and reverse total shoulder arthroplasty]

This article aims to present the principles of rehabilitation following anatomical and reverse total shoulder arthroplasties. The rehabilitation consist of three phases: wound healing and movement initiation (weeks 0-6), movement recovery (7-12), strengthening and return to activity (13-18). At 6 to 12 months follow-up, most patients report a substantial decrease in pain and a return to light to moderate activity level. The rehabilitation of the reverse arthroplasty specifically requires deltoid muscle strengthening and dislocation prevention. The functional outcome is slightly inferior for reverse arthroplasty, which is indicated when musculotendinous lesions are associated to bone lesions, but satisfaction rates are comparable between the two types of implants. The durability of total shoulder arthroplasties is globally satisfying, though shorter in young active patients

Detection and characterization of hydraulically active fractures in a carbonate aquifer: Results from self-potential, temperature and fluid conductivity logging along a 260-m-deep borehole in the Combioula hydrothermal system in the southwestern Swiss Alps

A geophysical and geochemical study has been conducted in a fractured carbonate aquifer located at Combioula in the southwestern Swiss Alps with the objective to detect and characterize hydraulically active fractures along a 260-m-deep borehole. Hydrochemical analyses, borehole diameter, temperature and fluid electrical conductivity logging data were integrated in order to relate electrokinetic self-potential signals to groundwater flow inside the fracture network. The results show a generally good, albeit locally variable correlation of variations of the self-potential signals with variations in temperature, fluid electrical conductivity and borehole diameter. Together with the hydrochemical evidence, which was found to be critical for the interpretation of the self-potential data, these measurements not only made it possible to detect the hydraulically active fractures but also to characterize them as zones of fluid gain or fluid loss. The results complement the available information from the corresponding litholog and illustrate the potential of electrokinetic self-potential signals in conjunction with temperature, fluid electrical conductivity and hydrochemical analyses for the characterization of fractured aquifers, and thus may offer a perspective for an effective quantitative characterization of this increasingly important class of aquifers and geothermal reservoirs