Quand l’inventaire se fait diagnostic : les édifices religieux dans le Finistère de 1801 à 1905

Le conseil général du Finistère a réalisé en huit mois, pendant l’année 2008, un inventaire exhaustif des édifices religieux publics construits entre le Concordat (1801) et la loi de séparation de l’Église et de l’État de 1905. Il est le préalable indispensable à la connaissance, à la valorisation et à la restauration de ces édifices. Considéré comme un outil d’aide à la décision, il permettra des interventions argumentées et raisonnées lors de la mise en place des budgets prévisionnels de subventions pour les restaurations futures grâce à une expertise sur l’intérêt architectural et patrimonial mais aussi sur l’état sanitaire actuel de ces édifices.The General Council of Finistère realized in eight months, during the year 2008, an exhaustive inventory of public religious buildings built between the Concordat (1801) and the separation law between The Church ant the State of 1905. It is the indispensable precondition to the knowledge, the valuation and the restoration of these buildings. Considered as a decision-making tool, it will allow argued and reasoned interventions during the setting up of the projected budgets of subsidies for the future restorations thanks to an expertise about the heritage and architectural interest but also about the current sanitary state of these buildings

In-situ synchrotron characterization of fracture initiation and propagation in shales during indentation

The feasibility and advantages of synchrotron imaging have been demonstrated to effectively characterise fracture initiation and propagation in shales during indentation tests. These include 1) fast (minute-scale) and high-resolution (μm-scale) imaging of fracture initiation, 2) concurrent spatial and temporal information (4D) about fracture development, 3) quantification and modelling of shale deformation prior to fracture. Imaging experiments were performed on four shale samples with different laminations and compositions in different orientations, representative of three key variables in shale microstructure. Fracture initiation and propagation were successfully captured in 3D over time, and strain maps were generated using digital volume correlation (DVC). Subsequently, post-experimental fracture geometries were characterized at nano-scale using complementary SEM imaging. Characterisation results highlight the influence of microstructural and anisotropy variations on the mechanical properties of shales. The fractures tend to kink at the interface of two different textures at both macroscale and microscale due to deformation incompatibility. The average composition appears to provide the major control on hardness and fracture initiation load; while the material texture and the orientation of the indentation to bedding combine to control the fracture propagation direction and geometry. This improved understanding of fracture development in shales is potentially significant in the clean energy applications

Linking multi-scale 3D microstructure to potential enhanced natural gas recovery and subsurface CO2 storage for Bowland shale, UK

Injection of CO2 into shale reservoirs to enhance gas recovery and simultaneously sequester greenhouse gases is a potential contributor towards the carbon-neutral target. It offers a low-carbon, low-cost, low-waste and large-scale solution during the energy transition period. A precondition to efficient gas storage and flow is a sound understanding of how the shale’s micro-scale impacts on these phenomena. However, the heterogeneous and complex nature of shales limits the understanding of microstructure and pore systems, making feasibility analysis challenging. This study qualitatively and quantitatively investigates the Bowland shale microstructure in 3D at five length scales: artificial fractures at 10–100 mm scale, matrix fabric at 1–10 mm-scale, individual mineral grains and organic matter particles at 100 nm–1 mm scale, macropores and micro-cracks at 10–100 nm scale and organic matter and mineral pores at 1–10 nm-scale. For each feature, the volume fraction variations along the bedding normal orientation, the fractal dimensions and the degrees of anisotropy were analysed at all corresponding scales for a multi-scale heterogeneity analysis. The results are combined with other bulk laboratory measurements, including supercritical CO2 and CH4 adsorption at reservoir conditions, pressure-dependent permeability and nitrogen adsorption pore size distribution, to perform a comprehensive analysis on the storage space and flow pathways. A cross-scale pore size distribution, ranging from 2 nm to 3 mm, was calculated with quantified microstructure. The cumulative porosity is calculated to be 8%. The cumulative surface area is 17.6 m2 g1 . A model of CH4 and CO2 flow pathways and storage with quantified microstructure is presented and discussed. The feasibility of simultaneously enhanced gas recovery and subsurface CO2 storage in Bowland shale, the largest shale gas potential formation in the UK, was assessed based using multi-scale microstructure analysis. The potential is estimated to store 19.0–21.2 Gt CO2 as free molecules, together with 18.3–28.5 Gt CO2 adsorbed onto pore surfaces, implying a theoretical maximum of 47.5–49.5 Gt carbon storage in the current estimate of 38 trillion cubic metres (B1300 trillion cubic feet) of Bowland shale. Simple estimates suggest 6.0–15.8 Gt CO2 may be stored in practice

Variability in spatial distribution of mineral phases in the Lower Bowland Shale, UK, from the mm- to μm-scale: quantitative characterization and modelling

The microstructure of a highly laminated Lower Bowland Shale sample is characterized at the micron-to millimeter scale, to investigate how such characterization can be utilized for microstructure-based modelling of the shale's geomechanical behavior. A mosaic of scanning electron microscope (SEM) back-scattered electron (BSE) images was studied. Mineral and organic content and their anisotropy vary between laminae, with a high variability in fracturing and multi-micrometer aggregates of feldspars, carbonates, quartz and organics. The different microstructural interface types and heterogeneities were located and quantified, demonstrating the microstructural complexity of the Bowland Shale, and defining possible pathways for fracture propagation. A combination of counting-box, dispersion, covariance and 2D mapping approaches were used to determine that the total surface of each lamina is 3 to 11 times larger than the scale of heterogeneities relative to mineral proportion and size. The dispersion approach seems to be the preferential technique for determining the representative elementary area (REA) of phase area fraction for these highly heterogeneous large samples, supported by 2D quantitative mapping of the same parameter. Representative microstructural models were developed using Voronoï tessellation using these characteristic scales. These models encapsulate the microstructural features required to simulate fluid flow through these porous Bowland Shales at the mesoscale

Étude par couplage CIN-MEB de l'influence de la microstructure sur les déformations par dessiccation de l'argilite de Tournemire

La relation entre les déformations par dessiccation de l’argilite de Tournemire et les propriétés texturales de la roche a été étudiée par un nouveau montage expérimental. Celui-ci se déroule en deux phases : la première utilise la méthode de corrélation d’images numériques (CIN) et la seconde la microscopie électronique à balayage (MEB). L’intérêt de cette manipulation est de pouvoir quantifier l’influence de la microstructure de l’argilite sur des déformations provoquées par des variations d’humidités. Dans une enceinte étanche, un échantillon provenant du forage FD90 du tunnel de Tournemire a été soumis à cycle de saturation-désaturation entre 98 et 33% d’humidité (98-33-98-33). L’échantillon se présente sous la forme d’un cube de 20x20x20mm3 et est filmé par deux caméras. La première caméra filme un champ large sur une face entière (25x20mm²) tandis que la seconde filme un champ zoomé (5.5x4.1mm²) sur une autre face. Le champ zoomé est ensuite analysé au MEB afin d’établir une cartographie des minéraux en électrons rétrodiffusés, qui sera comparée aux champs de déformations obtenus par CIN à partir des images des caméras. Ce montage expérimental permet d’étudier les champs de déformations dans deux directions (approximation du phénomène en 3D) à deux échelles différentes (millimétrique à micrométrique) avec la microstructure et la teneur en eau de la roche

Correlative multi-scale imaging of shales: A review and future perspectives

As the fastest growing energy sector globally, shale and shale reservoirs have attracted the attention of both industry and scholars. However, the strong heterogeneity at different scales and the extremely fine-grained nature of shales makes macroscopic and microscopic characterization highly challenging. Recent advances in imaging techniques have provided many novel characterization opportunities of shale components and microstructures at multiple scales. Correlative imaging, where multiple techniques are combined, is playing an increasingly important role in the imaging and quantification of shale microstructures (e.g. one can combine optical microscopy, scanning electron microscopy/transmission electron microscopy and X-ray radiography in 2D, or X-ray computed tomography and electron microscopy in 3D). Combined utilization of these techniques can characterize the heterogeneity of shale microstructures over a large range of scales, from macroscale to nanoscale (c. 100-10-9 m). Other chemical and physical measurements can be correlated to imaging techniques to provide complementary information for minerals, organic matter and pores. These imaging techniques and subsequent quantification methods are critically reviewed to provide an overview of the correlative imaging workflow. Applications of the above techniques for imaging particular features in different shales are demonstrated, and key limitations and benefits summarized. Current challenges and future perspectives in shale imaging techniques and their applications are discussed

Synchrotron tomographic quantification of strain and fracture during simulated thermal maturation of an organic-rich shale, UK Kimmeridge Clay

Analyzing the development of fracture networks in shale is important to understand both hydrocarbon migration pathways within and from source rocks and the effectiveness of hydraulic stimulation upon shale reservoirs. Here we use time‐resolved synchrotron X‐ray tomography to quantify in four dimensions (3‐D plus time) the development of fractures during the accelerated maturation of an organic‐rich mudstone (the UK Kimmeridge Clay), with the aim of determining the nature and timing of crack initiation. Electron microscopy (EM, both scanning backscattered and energy dispersive) was used to correlatively characterize the microstructure of the sample preheating and postheating. The tomographic data were analyzed by using digital volume correlation (DVC) to measure the three‐dimensional displacements between subsequent time/heating steps allowing the strain fields surrounding each crack to be calculated, enabling crack opening modes to be determined. Quantification of the strain eigenvectors just before crack propagation suggests that the main mode driving crack initiation is the opening displacement perpendicular to the bedding, mode I. Further, detailed investigation of the DVC measured strain evolution revealed the complex interaction of the laminar clay matrix and the maximum principal strain on incipient crack nucleation. Full field DVC also allowed accurate calculation of the coefficients of thermal expansion (8 × 10−5/°C perpendicular and 6.2 × 10−5/°C parallel to the bedding plane). These results demonstrate how correlative imaging (using synchrotron tomography, DVC, and EM) can be used to elucidate the influence of shale microstructure on its anisotropic mechanical behavior

Pronostic obstétrical, foetal et néonatal des grossesses diabétiques : comparaison du traitement par multi-injections quotidiennes versus pompe à insuline

Objectives : To evaluate and compare the obstetrical, fetal and neonatal outcome of pregnancies in diabetic women treated with mutiple daily insulin injections or insulin pump (continuous subcutaneous insulin infusion). Patients and methods : Forty-one patients from the University Hospital Center between January 2010 and June 2015, whose 15 treated with multiple injections and 26 with insulin pump. Were investigated : glycemic control (HbA1c), hypertensives complications occurrence, fetal growth, pregnancy and fetal outcomes. Results : Perconceptional glycemic control (HbA1c) with multiple injections was significantly better than with insulin pump (6,5% (+- 1,5%) vs 7,4% (+- 7,4)). The rates of preterm deliveries (6,7% vs 46,2%) and macrosomia (33,3% vs 69,2%) were higher with pump. Except those criteria, the maternofetal outcome is similar for those two treatments.Discussion and conclusion : Compared to conventional treatment, insulin pump doesn t significantly change the maternofetal outcome. Medical care must be done with patient s agreement after assessment of the benefits risks ratio. It is necessary that patient receive adapted therapeutic education and, if possible, pregnancy should be planned to minimise the risks for the mother and the child.Objectifs : Évaluer et comparer le pronostic obstétrical, fœtal et néonatal de grossesses chez des femmes diabétiques traitées par multi-injections ou pompe à insuline (infusion continue sous-cutanée d'insuline). Patientes et méthodes : Quarante-et-une patientes suivies au CHU de Caen (Normandie) entre janvier 2010 et juin 2015, dont 15 traitées par multi-injections et 26 par pompe à insuline. Ont été évalués : l'équilibre glycémique (HbA1c), la survenue de complications hypertensives, la croissance fœtale, l'issue de la grossesse et le devenir néonatal. Résultats : L'équilibre glycémique périconceptionnel (HbA1c) sous multi-injections était significativement meilleur que sous pompe à insuline (6,5% (+- 1,5%) vs 7,4% (+- 7,4%)). Les taux de prématurité (6,7% vs 46,2%) et de macrosomie (33,3% vs 69,2%) étaient plus importants sous pompe. Hormis ces trois critères, le pronostic materno-fœtal est similaire pour les deux traitements. Discussion et conclusion : Comparé au traitement conventionnel, la pompe à insuline ne modifie pas significativement le pronostic materno-fœtal. La prise en charge doit se faire en accord avec la patiente après analyse de la balance bénéfice-risque. Il est nécessaire que la patiente reçoive une éducation thérapeutique adaptée et, si possible, la grossesse devrait être planifiée afin de minimiser les risques pour la mère et l'enfant

Quand l’inventaire se fait diagnostic : les édifices religieux dans le Finistère de 1801 à 1905

The General Council of Finistère realized in eight months, during the year 2008, an exhaustive inventory of public religious buildings built between the Concordat (1801) and the separation law between The Church ant the State of 1905. It is the indispensable precondition to the knowledge, the valuation and the restoration of these buildings. Considered as a decision-making tool, it will allow argued and reasoned interventions during the setting up of the projected budgets of subsidies for the future restorations thanks to an expertise about the heritage and architectural interest but also about the current sanitary state of these buildings

Évaluation des pratiques sur la sédation-analgésie-procédurale en médecine d’urgence hospitalière et préhospitalière

Introduction: The procedural sedation is based on the administration of pharmaceutical agents which allows the performance of very painful and short acts in hospital and pre-hospital emergency structure. It benefits from guidelines dating from 2010.Method:It is a national, multicentric, descriptive study based on an online questionnaire, addressed to a panel of emergency physicians in France between February and June 2022. Goal:Determine if the practice of procedural sedation by emergency physicians in France is consistent with the guidelinesResults:423 physicians distributed throughout France answered to the questionnaire. The practice described here are globally consistent with the guidelines. The main factor of divergence to the guidelines is the dose administered by the physicians: 56.3% of them use the Ketamine at the dose of 0.3 to 0.5 mg/kg, lower than the recommended dose, 24.6% use the Propofol at the dose of 0.5 mg/kg, half as much as the recommended dose. Conclusion:The practices in terms of procedural sedation, even though remaining heterogeneous, are globally consistent with the guidelines, both in terms of pharmacological choices and peri-procedural practice. Areas of improvment exist, with the edition of protocols and upgrading the existing guideline.Introduction : la sédation analgésie procédurale repose sur l’administration d’agents pharmacologiques permettant la réalisation d’actes courts et très douloureux, en structure d’urgence intrahospitalière ou extrahospitalière. Elle bénéficie de recommandations datant de 2010. Méthode : il s’agit d’une étude descriptive multicentrique nationale basée sur un questionnaire en ligne adressé à un panel de médecins urgentistes en France entre février et juin 2022. Objectif : déterminer si la pratique de la sédation analgésie procédurale (SAP) par les médecins urgentistes en France est conforme aux recommandations. Résultats : 423 médecins urgentistes ont répondu. Les pratiques décrites étaient conformes aux recommandations. Les principaux points de divergences sont les posologies d’agent sédatif administrées par les praticiens : 56,3% des participants utilisent la Kétamine à une posologie de 0,3 à 0,5 mg/kg, inférieure à celle recommandées, 24,6% utilisent le Propofol à une posologie de 0,5 mg/kg, moitié moins élevée que celle recommandée. Conclusion : les pratiques de la SAP, bien que restant hétérogènes, sont globalement conformes aux recommandations, tant sur le plan des choix pharmacologiques que sur le plan des pratiques péri-procédurales. Des axes d’amélioration existent, avec l’édition de protocole de service, et la mise à jour des recommandations