Permafrost extension modeling in rock slope since the Last Glacial Maximum: application to the large Séchilienne landslide (French Alps).

12 pagesInternational audienceRecent dating performed on large landslides in the Alps reveal that the initiation of instability did not immediately follow deglaciation but occurred several thousand years after ice down-wastage in the valleys. This result indicates that debuttressing is not the immediate cause of landslide initiation. The period of slope destabilization appears to coincide with the wetter and warmer Holocene Climatic Optimum, indicating a climatic cause of landslide triggering, although the role of seismic activity cannot be ruled out. A phenomenon which may partly explain the delay between valley deglaciation and gravitational instability is the temporal persistence of thick permafrost layers developed in the Alps since the Last Glacial Maximum (LGM). This hypothesis was tested through 2D thermal numerical modeling of the large Séchilienne landslide (Romanche valley, French Alps) using plausible input parameter values. Simulation results suggest that permafrost vanished in the Séchilienne slope at 10 to 11 ka, 3,000 to 4,000 years following the total ice down-wastage of the Romanche valley at 14.3 ka. Permafrost persistence could have contributed to the failure delay by temporally strengthening the slope. Numerical simulations also show that the permafrost depth expansion approximately fits the thickness of ground affected by gravitational destabilization, as deduced from geophysical investigations. These results further suggest that permafrost development, associated with an ice segregation mechanism, damaged the rock slope and influenced the resulting landslide geometry

Insulin induces a positive relationship between the rates of ATP and glycogen changes in isolated rat liver in presence of glucose; a (31)P and (13)C NMR study

BACKGROUND: There is an emerging theory suggesting that insulin, which is known to be the predominant postprandial anabolic hormone, is also a major regulator of mitochondrial oxidative phosphorylation in human skeletal muscle. However, little is known about its effects in the liver. Since there is a theoretical relationship between glycogen metabolism and energy status, a simultaneous and continuous investigation of hepatic ATP and glycogen content was performed in intact and isolated perfused liver by (31)P and (13)C nuclear magnetic resonance (NMR) The hepatic rates of ATP and glycogen changes were evaluated with different concentrations of insulin and glucose during continuous and short-term supply. RESULTS: Liver from rats fed ad libitum were perfused with Krebs-Henseleit Buffer (KHB)(controls) or KHB containing 6 mM glucose, 30 mM glucose, insulin alone, insulin + 6 mM glucose, insulin + 30 mM glucose. In the control, glycogenolysis occurred at a rate of -0.53 ± 0.021 %·min(-1) and ATP content decreased at a rate of -0.28 ± 0.029 %·min(-1). In the absence of insulin, there was a close proportional relationship between the glycogen flux and the glucose concentration, whereas ATP rates never varied. With insulin + glucose, both glycogen and ATP rates were strongly related to the glucose concentration; the magnitude of net glycogen flux was linearly correlated to the magnitude of net ATP flux: flux(glycogen )= 72.543(flux(ATP)) + 172.08, R(2 )= 0.98. CONCLUSION: Only the co-infusion of 30 mM glucose and insulin led to (i) a net glycogen synthesis, (ii) the maintenance of the hepatic ATP content, and a strong positive correlation between their net fluxes. This has never previously been reported. The specific effect of insulin on ATP change is likely related to a rapid stimulation of the hepatic mitochondrial oxidative phosphorylation. We propose that variations in the correlation between rates of ATP and glycogen changes could be a probe for insulin resistance due to the action of substrates, drugs or pathologic situations. Consequently, any work evaluating insulin resistance on isolated organs or in vivo should determine both ATP and glycogen fluxes

The French National 3D Data Repository for Humanities: Features, Feedback and Open Questions

We introduce the French National 3D Data Repository for Humanities designed for the conservation and the publication of 3D research data in the field of Humanities and Social Sciences. We present the choices made for the data organization, metadata, standards and infrastructure towards a FAIR service. With 437 references at the time of the writing, we have feedback on some challenges to develop such a service and to make it widely used. This leads to open questions and future developments.Comment: CAA 2021 - "Digital Crossroads" full paper version (in review

Share - Publish - Store - Preserve. Methodologies, Tools and Challenges for 3D Use in Social Sciences and Humanities

Through this White Paper, which gathers contributions from experts of 3D data as well as professionals concerned with the interoperability and sustainability of 3D research data, the PARTHENOS project aims at highlighting some of the current issues they have to face, with possible specific points according to the discipline, and potential practices and methodologies to deal with these issues. During the workshop, several tools to deal with these issues have been introduced and confronted with the participants experiences, this White Paper now intends to go further by also integrating participants feedbacks and suggestions of potential improvements. Therefore, even if the focus is put on specific tools, the main goal is to contribute to the development of standardized good practices related to the sharing, publication, storage and long-term preservation of 3D data

Mapping neurotransmitter systems to the structural and functional organization of the human neocortex

Neurotransmitter receptors support the propagation of signals in the human brain. How receptor systems are situated within macro-scale neuroanatomy and how they shape emergent function remain poorly understood, and there exists no comprehensive atlas of receptors. Here we collate positron emission tomography data from more than 1,200 healthy individuals to construct a whole-brain three-dimensional normative atlas of 19 receptors and transporters across nine different neurotransmitter systems. We found that receptor profiles align with structural connectivity and mediate function, including neurophysiological oscillatory dynamics and resting-state hemodynamic functional connectivity. Using the Neurosynth cognitive atlas, we uncovered a topographic gradient of overlapping receptor distributions that separates extrinsic and intrinsic psychological processes. Finally, we found both expected and novel associations between receptor distributions and cortical abnormality patterns across 13 disorders. We replicated all findings in an independently collected autoradiography dataset. This work demonstrates how chemoarchitecture shapes brain structure and function, providing a new direction for studying multi-scale brain organization.</p

Cardiovasc Diabetol

Lower-extremity arterial disease (LEAD) is a major endemic disease with an alarming increased prevalence worldwide. It is a common and severe condition with excess risk of major cardiovascular events and death. It also leads to a high rate of lower-limb adverse events and non-traumatic amputation. The American Diabetes Association recommends a widespread medical history and clinical examination to screen for LEAD. The ankle brachial index (ABI) is the first non-invasive tool recommended to diagnose LEAD although its variable performance in patients with diabetes. The performance of ABI is particularly affected by the presence of peripheral neuropathy, medial arterial calcification, and incompressible arteries. There is no strong evidence today to support an alternative test for LEAD diagnosis in these conditions. The management of LEAD requires a strict control of cardiovascular risk factors including diabetes, hypertension, and dyslipidaemia. The benefit of intensive versus standard glucose control on the risk of LEAD has not been clearly established. Antihypertensive, lipid-lowering, and antiplatelet agents are obviously worthfull to reduce major cardiovascular adverse events, but few randomised controlled trials (RCTs) have evaluated the benefits of these treatments in terms of LEAD and its related adverse events. Smoking cessation, physical activity, supervised walking rehabilitation and healthy diet are also crucial in LEAD management. Several advances have been achieved in endovascular and surgical revascularization procedures, with obvious improvement in LEAD management. The revascularization strategy should take into account several factors including anatomical localizations of lesions, medical history of each patients and operator experience. Further studies, especially RCTs, are needed to evaluate the interest of different therapeutic strategies on the occurrence and progression of LEAD and its related adverse events in patients with diabetes

The vegetated decorations in Greek architecture : the lesbic kyma : analysis, volumetric reconstruction and interpretation by the 3D render

Cette thèse met en avant une démarche originale, celle de faire cohabiter l'utilisation d'une technologie moderne, au sein d'une étude archéologique conventionnelle centrée sur l'architecture grecque. L'utilisation de la modélisation 3D dans ce projet doctoral nous amène indubitablement à explorer de nouvelles problématiques en archéologie grecque. Pour ce faire, une réflexion sera menée sur les apports de cette technologie aux sciences archéologiques. En effet, la restitution d'un édifice antique en 3D implique des questionnements sur la réalité virtuelle créée. La modélisation 3D se fonde sur du matériel archéologique partiel altéré par le temps. C'est pourquoi il est nécessaire de prendre du recul face à une image 3D qui peut idéaliser une réalité archéologique. Notre étude s'appliquera aussi à apporter des solutions permettant de remédier à ces complications liées à la restitution virtuelle. De plus, la restitution 3D d'un édifice antique n'est pas une fin en soi. En d'autres termes, cette technologie doit par son approche intuitive apporter une nouvelle façon d'appréhender les questions qui touchent à la construction des édifices antiques. À commencer par les méthodes de constructions ou encore la faisabilité architecturale...etc. Dans un même temps, nous mènerons un examen architectural et archéologique dans le but de proposer une étude qui soit équilibrée et qui puisse être réutilisée par la recherche archéologique. Nos objectifs sont multiples et cette étude fait le vœu d'être ambitieuse. Pour cela, cette étude s'attellera à éviter l'écueil de proposer une approche ayant un cadre trop restrictif. C'est pourquoi nous envisageons de préférence une étude qui associera plusieurs groupes d'édifices aux fonctions différentes. De ce fait, en tenant compte d'un maximum de situations et de réalités archéologiques, notre examen gagnera en représentativité, tout comme cela lui assurera une probabilité plus grande d'être réutilisé dans la recherche pour d'autres applications liées à la restitution 3D. Cette thèse est aussi une occasion d'évoquer les questions liées à la valorisation du patrimoine culturel. Ce thème sera aussi abordé, car le partage du savoir ne doit pas seulement être destiné aux initiés, mais aussi auprès du grand public. Il s'agit là d'une mission essentielle que l'archéologie se doit de mener à bien.This thesis puts forward a novel approach who will make cohabit together the use of a modern technology in a conventional archaeological study focused on Greek architecture. The use of 3D modeling in this doctoral project leads undoubtedly to explore new issues in the Greek archeology. To do this, we will consider to the benefits of this technology to archaeological sciences. Indeed, the restitution of an ancient building in 3D, involves questions on the virtual reality that created. 3D modeling is based on the archaeological material altered by the time. That is why, it is necessary to take a step back on a 3D picture that can idealize an archaeological reality. Our study will also apply to provide solutions to overcome these complications of the virtual restitution. Moreover, the 3D rendition of an ancient building is not an end in itself. In other words, this technology must provide a intuitive approach and a new way to understand the issues that affect at the construction of ancient buildings. Starting with the construction methods or architectural feasibility ... etc.. At the same time, we will conduct an architectural and archaeological examination in order to propose a study that is balanced and that can be reused by archaeological research. Our goals are many and this study wants to be ambitious. For this, this study will strive to avoid the pitfall of proposing an approach that is too restrictive. That is why we plan to combine preferably a study several groups of buildings with different functions. Therefore, taking into account a maximum of archaeological situations our study will be more representative, as this will ensure it a greater likelihood of being reused in the archeological studies. This thesis is also an opportunity to discuss issues related to the promotion of cultural heritage. This topic will also be addressed because the sharing of knowledge should not be accessible only to insiders, but it must also be affordable for the general public. This is an essential task that archeology must carry

Le temple d’Apollon au IVe siècle à Delphes : anastylose 3D des colonnes de la péristasis

L’étude des colonnes de la péristasis au temple oraculaire d’Apollon à Delphes, reconstruit au IVe siècle av. J.-C., est un dossier qui ne fut jamais complètement résolu. Depuis la découverte du monument en 1893, les restitutions du péristyle ont largement varié d’un spécialiste à un autre. Les travaux de F. Courby en 1927 ont ouvert la voie vers un premier essai de restitution, dont les conclusions seront contestées une décennie plus tard par l’anastylose matérielle menée par H. Ducoux. Les recherches les plus récentes publiées par P. Amandry et E. Hansen finiront par s’opposer aux résultats de cette anastylose, sans résoudre définitivement la question du nombre de tambours, ainsi que la hauteur définitive de la colonnade. Le présent article propose de retracer les raisons qui expliquent l’absence de certitudes, et également d’exposer des éléments factuels inédits qui militent en faveur d’un réexamen complet de la question. Pour ce faire, nous opérerons une anastylose 3D bloc à bloc de la colonnade qui constituera une synthèse de l’ensemble des connaissances considéré comme certaines conjugué à des données nouvellement acquises

Chapter 12

The lesbian kymation is one of the most important and enduring decorative motifs in Greek architecture. The association of the words kymation, or kyma, and lesbian, or lesbicum, designates with an inflection point that features a carved sequence of heart shapes alternating with spearheads. Its longevity within decorative record of the Archaic to the Roman period and its spread throughout the ancient Mediterranean, from Sicily to continental Greece, a curvilinear molding Asia Minor, and modern Syria, attest to the value of this ornament as a critical archaeological witness.The region of northern Greece has a large sample of carved lesbian kymatia, mostly concentrated on the islands of Thasos and Samothrace. The aim of this study is to explore the connections between the architecture of Thasos and Samothrace during the Archaic and Hellenistic periods through the lesbian kymation, using a novel comparative protocol founded on photogrammetry by dense correlation. In this procedure, it is possible to extract the profile, motif, and the relief of a lesbian kymation by means of a digital replica produced by photogrammetry. As a result, this process allows for a more precise and systematic comparison of significant features of the moldings that can reveal stylistic affiliations. With this comparative protocol, it is possible to examine Greek decorative motifs by comparing morphologies through successive overlaps. These comparisons are more likely to reveal special features inherent to a workshop, reflect possible influences moving from one area to another, or to trace the existence of itinerant workshops