L’activité métallurgique à l’abbaye de Morimond (Haute-Marne) : nouvel éclairage de la fouille à partir de l’analyse archéomagnétique de deux foyers

Une étude archéomagnétique à des fins de datation a été menée sur deux foyers en carreaux de terre cuite mis au jour sur le site de l’ancienne abbaye cistercienne de Morimond (Haute-Marne). La désaimantation thermique complète des échantillons prélevés a permis de définir pour chacun des deux foyers une direction archéomagnétique moyenne précise, acquise lors de leur dernière utilisation. Pour dater cet instant, les directions archéomagnétiques ont été comparées à une courbe des variations directionnelles du champ géomagnétique construite à partir de données obtenues en France et dans des pays voisins. Nous obtenons, à 95% de confiance, une datation comprise entre 1585 et 1615 après J.-C. pour le premier foyer et entre 1525 et 1605 après J.-C. pour le second foyer. Bien que leurs deux intervalles d'âge se recouvrent partiellement, les deux directions archéomagnétiques moyennes ne sont pas compatibles à 95% ce qui indique que les arrêts de fonctionnement des deux foyers ne sont pas contemporains. Ces résultats archéomagnétiques confirment deux phases métallurgiques observées indépendamment lors des fouilles. Ils précisent les datations issues des radiocarbones qui ne permettaient pas de discriminer chronologiquement les deux phases. Les datations envisagées se calent avant l’abandon du bâtiment suite à plusieurs saccages évoqués dans les sources écrites.This paper presents the archeomagnetic dating results obtained from two brick fireplaces excavated inside the ancient Cistercian Abbey of Morimond (Haute-Marne). Complete thermal demagnetization of the collected samples allowed us to define a precise mean archeomagnetic direction acquired during the last cooling of each of the two structures. The dating of the last use of the two fireplaces was derived from the statistical comparison between a reference geomagnetic field directional variation curve constructed using the available French data set together with other data from nearby countries and the two directions obtained in this study. The two dating results lie, with a 95% confidence level, between 1585 and 1615 AD and between 1525 and 1605 AD. Although these dates partially overlap, the two mean archeomagnetic directions are not compatible at the 95% confidence level, indicating a chronology in the abandonment of the two structures. These archeomagnetic results therefore confirm the existence of two metallurgical phases, which were independently observed during the excavations. They further refine the radiocarbon dating unable to discriminate the two phases. The two time intervals defined by archeomagnetism pre-date the abandonment of the building due to severe damages mentioned in written sources

The GeDSeT project: constitution of a decision support tool (DST) for the management and material recovery of waterways sediments in Belgium and Northern France

International audienceThe European InterReg IV GeDSeT project (2008-2011) is a contribution to a sustainable management of waterways sediments, in order to develop good practice in a perspective of water resource protection and of the development of regional fluvial transport. Waterways sediments are a major environmental issue in the Walloon region of Belgium - Northern France trans-boundary region for several reasons, all of them resulting from the dense habitat, industrial pattern and waterways network, and of a long industrial history. Sediments affect water resources quality, through pollution, and availability, through flooding. Sediment dredging allows the development of environmentally-friendly regional fluvial transport, but also generates important waste deposits. Therefore material recovery for reuse in buildings or infrastructure is a key issue, as it allows a reduction of waste and limits the need for natural resources for the same use. In order to address waterways sediments management in a global way, the GeDSeT project intends to capitalise know-how regarding the criteria to take into account for a sustainable management, and to include them in a decision support methodology applicable to the transboundary context. Such decision support aims at developing good practice in a perspective of water resource management and development of regional fluvial transport. Relevant criteria include: - criteria evaluating the physical and chemical characteristics of the sediments to be dredged, and their level of contamination, - costs of dredging operations and benefits with respect to improved waterways, - potential material value and costs of sediment treatment for material recovery versus costs of sediment deposit management. The decision support methodology will rely in part on previous BRGM and European experience in the development of an environmentally extended, physical, quasi-dynamic input-output model for waste management. Experience from other specific DSTs on sediments will be valorised with the project partners. Potential recovery of secondary resources from dredged sediment will be addressed through a review and economic evaluation of available technologies, technical and economical constraints, side effects on the uses of recovered products, and a global balance of the environmental costs and benefits. Social and employment impacts, as well as land use issues in this densely populated area will be fully acknowledged as primary decision-support criteria. The expected benefit of the project comprises also the transboundary comparison of specific situations and methods, issued from a different history.Le projet InterReg IV GeDSeT (2008-2011) est une contribution à une gestion globale durable des sédiments des voies d’eau, au développement du transport régional fluvial et de bonnes pratiques pour la protection des ressources en eau et de l’espace urbain.Les sédiments des voies d’eau sont un enjeu majeur en Europe, et particulièrement dans la région transfrontalière Belgique Wallonie – Nord de la France pour plusieurs raisons, toutes liées à la densité de l’habitat, du tissu industriel passé et présent, et du réseau de voies d’eau. Non seulement les sédiments affectent la navigabilité, mais aussi la qualité des ressources en eau, par la pollution, et la gestion des inondations. Le curage régulier des sédiments permet le développement d’un transport régional fluvial éco-favorable, mais génère d’importants volumes de déchets potentiels. La réutilisation des sédiments pour la construction ou les infrastructures est donc un enjeu clé, en combinant réduction des déchets et des besoins en ressources naturelles pour le même usage.Afin de prendre en compte la problématique des sédiments fluviaux dans sa globalité, le projet GeDSeT va capitaliser l’état de l’art sur les critères pertinents pour une gestion durable, et les incorporer dans une méthodologie d’aide à la décision applicable au contexte transfrontalier. Cette méthodologie vise à développer des bonnes pratiques en harmonie avec la gestion des ressources en eau, et le développement du transport fluvial régional

Digging deeper into lymphatic vessel formation in vitro and in vivo

Background Abnormal lymphatic vessel formation (lymphangiogenesis) is associated with different pathologies such as cancer, lymphedema, psoriasis and graft rejection. Lymphatic vasculature displays distinctive features than blood vasculature, and mechanisms underlying the formation of new lymphatic vessels during physiological and pathological processes are still poorly documented. Most studies on lymphatic vessel formation are focused on organism development rather than lymphangiogenic events occurring in adults. We have here studied lymphatic vessel formation in two in vivo models of pathological lymphangiogenesis (corneal assay and lymphangioma). These data have been confronted to those generated in the recently set up in vitro model of lymphatic ring assay. Ultrastructural analyses through Transmission Electron Microscopy (TEM) were performed to investigate tube morphogenesis, an important differentiating process observed during endothelial cell organization into capillary structures

Closure of radial forearm free flap donor site: A comparative study between keystone flap and skin graft

Background The aim was to investigate the feasibility of radial forearm free flap (RFFF) donor site closure by keystone flap (KF) and compare its outcomes to those of skin graft (SG) closure. Methods One hundred and one patients who underwent RFFF for head and neck reconstruction were included (35 KF closure and 65 SG closure). Duration of wound healing and donor site complications was collected. After a minimal follow‐up of 1 year, patients were questioned about functional and esthetic impairment. Results Coverage of donor site by KF was successful in all cases. The duration of wound healing was longer after SG than after KF (32 days vs 18 days, P < .001). Healing complications, esthetic and functional results were not statistically different. Conclusion Forearm donor site closure by KF is a feasible alternative to the traditional SG. Its main advantages are the reduced wound healing time and the avoidance of a second donor site

End-User Modelling

National audienceno abstrac

Conditional BDNF delivery from astrocytes rescues memory deficits, spine density and synaptic properties in the 5xFAD mouse model of Alzheimer disease

It has been well documented that neurotrophins, including brain-derived neurotrophic factor (BDNF), are severely affected in Alzheimer's disease (AD), but their administration faces a myriad of technical challenges. Here we took advantage of the early astrogliosis observed in an amyloid mouse model of AD (5xFAD) and used it as an internal sensor to administer BDNF conditionally and locally. We first demonstrate the relevance of BDNF release from astrocytes by evaluating the effects of coculturing WT neurons and BDNF-deficient astrocytes. Next, we crossed 5xFAD mice with pGFAP:BDNF mice (only males were used) to create 5xFAD mice that overexpress BDNF when and where astrogliosis is initiated (5xF:pGB mice). We evaluated the behavioral phenotype of these mice. We first found that BDNF from astrocytes is crucial for dendrite outgrowth and spine number in cultured WT neurons. Double-mutant 5xF:pGB mice displayed improvements in cognitive tasks compared with 5xFAD littermates. In these mice, there was a rescue of BDNF/TrkB downstream signaling activity associated with an improvement of dendritic spine density and morphology. Clusters of synaptic markers, PSD-95 and synaptophysin, were also recovered in 5xF:pGB compared with 5xFAD mice as well as the number of presynaptic vesicles at excitatory synapses. Additionally, experimentally evoked LTP in vivo was increased in 5xF:pGB mice. The beneficial effects of conditional BDNF production and local delivery at the location of active neuropathology highlight the potential to use endogenous biomarkers with early onset, such as astrogliosis, as regulators of neurotrophic therapy in AD.SIGNIFICANCE STATEMENT Recent evidence places astrocytes as pivotal players during synaptic plasticity and memory processes. In the present work, we first provide evidence that astrocytes are essential for neuronal morphology via BDNF release. We then crossed transgenic mice (5xFAD mice) with the transgenic pGFAP-BDNF mice, which express BDNF under the GFAP promoter. The resultant double-mutant mice 5xF:pGB mice displayed a full rescue of hippocampal BDNF loss and related signaling compared with 5xFAD mice and a significant and specific improvement in all the evaluated cognitive tasks. These improvements did not correlate with amelioration of β amyloid load or hippocampal adult neurogenesis rate but were accompanied by a dramatic recovery of structural and functional synaptic plasticity

Nrf2, a PPARγ Alternative Pathway to Promote CD36 Expression on Inflammatory Macrophages: Implication for Malaria

CD36 is the major receptor mediating nonopsonic phagocytosis of Plasmodium falciparum-parasitized erythrocytes by macrophages. Its expression on macrophages is mainly controlled by the nuclear receptor PPARγ. Here, we demonstrate that inflammatory processes negatively regulate CD36 expression on human and murine macrophages, and hence decrease Plasmodium clearance directly favoring the worsening of malaria infection. This CD36 downregulation in inflammatory conditions is associated with a failure in the expression and activation of PPARγ. Interestingly, using siRNA mediating knock down of Nrf2 in macrophages or Nrf2- and PPARγ-deficient macrophages, we establish that in inflammatory conditions, the Nrf2 transcription factor controls CD36 expression independently of PPARγ. In these conditions, Nrf2 activators, but not PPARγ ligands, enhance CD36 expression and CD36-mediated Plasmodium phagocytosis. These results were confirmed in human macrophages and in vivo where only Nrf2 activators improve the outcome of severe malaria. Collectively, this report highlights that the Nrf2 transcription factor could be an alternative target to PPARγ in the control of severe malaria through parasite clearance