Clay fine fissuring monitoring using miniature geo-electrical resistivity arrays

Abstract This article describes a miniaturised electrical imaging (resistivity tomography) technique to map the cracking pattern of a clay model. The clay used was taken from a scaled flood embankment built to study the fine fissuring due to desiccation and breaching process in flooding conditions. The potential of using a miniature array of electrodes to follow the evolution of the vertical cracks and number them during the drying process was explored. The imaging technique generated two-dimensional contoured plots of the resistivity distribution within the model before and at different stages of the desiccation process. The change in resistivity associated with the widening of the cracks were monitored as a function of time. Experiments were also carried out using a selected conductive gel to slow down the transport process into the cracks to improve the scanning capabilities of the equipment. The main vertical clay fissuring network was obtained after inversion of the experimental resistivity measurements and validated by direct observations

Electrical multi-depth survey to assess soil cover spatial organization

International audienceGeophysical technics can be a great help for soil mapping since they are non-destructive and fast. Electrical data from a 3-depth survey, usually treated as three apparent resistivity maps, are considered here as many electrical soundings with three apparent resistivity values. The study of the vertical succession of these values led to a geophysical taxonomy. Geophysical taxa mapping shows that their spatial distribution is related to pedological characteristics. Compared to a pre-existing soil map, the delineations of taxon clusters closely matched soil units boundaries and leads to the assignment to each soil type of a specific apparent electrical resistivity profile

A rapidly evolving landscape: immune checkpoint inhibitors in pretreated metastatic endometrial cancer

Background and objectives: Endometrial cancer is a common malignancy and recurrences can be fatal. Although platinum-pretreated endometrial tumors are commonly treated with anthracyclines and taxanes, there is no current standard of care. Both immune checkpoint inhibitors (ICIs) and tyrosine kinase inhibitors (TKIs) have been extensively assessed in this setting, including tumors selected for DNA mismatch repair (MMR)/microsatellite instability (MSI) and programmed death-ligand 1 expression status. This review will provide evidence-based guidance on use of ICIs alone or in combination with TKIs in patients with pretreated advanced, persistent, or recurrent metastatic endometrial cancer. Data sources and methods: Randomized phase II–III trials in unselected populations pretreated, recurrent, or metastatic endometrial cancer and phase I–II trials in biomarker selected populations were identified from PubMed as well as conference proceedings using the key search terms ‘immune checkpoint inhibitors’, ‘endometrial cancer’, and ‘advanced’. Results: A total of nine eligible studies were identified assessing ICI monotherapy for biomarker-selected or ICI plus TKI combinations and a dual ICI regimen for biomarker-unselected patients with pretreated recurrent or metastatic endometrial cancer. In MMR/MSI-selected tumors, five phase I/II studies evaluated ICI monotherapy indicating benefit in these patients. Only the phase III KEYNOTE-775 trial reported a statistically significant overall survival improvement for the combination of pembrolizumab plus lenvatinib compared with docetaxel or paclitaxel regardless of MMR/MSI status. Conclusions: Pembrolizumab plus lenvatinib is indicated for patients with unselected pretreated metastatic endometrial cancer and pembrolizumab monotherapy is a preferred option for patients with MMRd/MSI-H tumors

Evaluation of instruments for monitoring the soil–plant continuum

International audienceThe response of the shallow portion of the ground (vadose zone) and of earth structures is affected by the interaction with the atmosphere. Very frequently, the ground surface is covered by vegetation and, as a result, transpiration plays a major role in ground–atmosphere​ interaction. The soil and the plant form a continuous hydraulic system that needs to be characterised to model the ‘boundary condition’ of the geotechnical water flow problem. Water flow in soil and plant takes place because of gradients in hydraulic head triggered by the water tension (negative water pressure) generated in the leaf stomata. To study the response of the soil–plant continuum, water tension needs to be measured not only in the soil but also in the plant (in addition to the water content in the soil). This paper first evaluates three instruments that can be used to measure xylem water tension, i.e. the High-Capacity Tensiometer (HCT) and the Thermocouple Psychrometer (TP) for continuous non-destructive measurement on the stem, and the Pressure Chamber (PC) for discontinuous destructive measurement on the leaves. Experimental procedures are presented and critically discussed, including data quality control and instrument calibration, accuracy, and precision. The performance of these three instruments is evaluated in terms of measurement precision and measurement accuracy via cross-validation. The paper then addresses the problem of monitoring soil suction (pore-water tension) and water content using a second generation profile probe (fully encapsulated) and the use of Electrical Resistivity Tomography (ERT) for coarse characterisation of water content spatial distribution to support the design of spatial configuration of suction and water content sensors