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Limoges, France

The University of Limoges is a French public research university, based in Limoges. The semiotician Jacques Fontanille, a senior member of the "Institut Universitaire de France", is the president. Its chancellor is the rector of the Academy of Limoges . It counts more than 14,000 students and near 1,000 scholars and researchers. It offers complete curricula up to the doctorates and beyond in the traditional areas of knowledge and continues to develop new courses in line with the evolution of the postmodern and postcolonial society. It is a member of the Center Atlantic University PRES with the University of Poitiers, the University of La Rochelle and several engineering schools. Wikipedia.

Azouzi M.E.M.,University Claude Bernard Lyon 1 | Ramboz C.,CNRS Earth Sciences Institute of Orleans | Lenain J.-F.,University of Limoges | Caupin F.,University Claude Bernard Lyon 1
Nature Physics | Year: 2013

Liquid water at atmospheric pressure can be supercooled to -41C (ref.) and superheated to +302C (ref.). Experiments involving fluid inclusions of water in quartz suggest that water is capable of sustaining pressures as low as -140 MPa before it breaks by cavitation. Other techniques, for which cavitation occurs consistently at around -30 MPa (ref.), produce results that cast doubt on this claim. Here we reproduce the fluid-inclusion experiment, performing repeated measurements on a single sample - a method used in meteorology, bioprotection and protein crystallization, but not yet in liquid water under large mechanical tension. The resulting cavitation statistics are characteristic of a thermally activated process, and both the free energy and the volume of the critical bubble are well described by classical nucleation theory when the surface tension is reduced by less than 10%, consistent with homogeneous cavitation. The line of density maxima of water at negative pressure is found to reach 922.8 kg m -3 at around 300 K, which further constrains its contested phase diagram. © 2013 Macmillan Publishers Limited.

Champion E.,University of Limoges
Acta Biomaterialia | Year: 2013

Calcium phosphate ceramics have become of prime importance for biological applications in the field of bone tissue engineering. This paper reviews the sintering behaviour of these bioceramics. Conventional pressureless sintering of hydroxyapatite, Ca10(PO4)6(OH)2, a reference compound, has been extensively studied. Its physico-chemistry is detailed. It can be seen as a competition between two thermally activated phenomena that proceed by solid-state diffusion of matter: densification and grain growth. Usually, the objective is to promote the first and prevent the second. Literature data are analysed from sintering maps (i.e. grain growth vs. densification). Sintering trajectories of hydroxyapatite produced by conventional pressureless sintering and non-conventional techniques, including two-step sintering, liquid phase sintering, hot pressing, hot isostatic pressing, ultrahigh pressure, microwave and spark plasma sintering, are presented. Whatever the sintering technique may be, grain growth occurs mainly during the last step of sintering, when the relative bulk density reaches 95% of the maximum value. Though often considered very advantageous, most assisted sintering techniques do not appear very superior to conventional pressureless sintering. Sintering of tricalcium phosphate or biphasic calcium phosphates is also discussed. The chemical composition of calcium phosphate influences the behaviour. Similarly, ionic substitutions in hydroxyapatite or in tricalcium phosphate create lattice defects that modify the sintering rate. Depending on their nature, they can either accelerate or slow down the sintering rate. The thermal stability of compounds at the sintering temperature must also be taken into account. Controlled atmospheres may be required to prevent thermal decomposition, and flash sintering techniques, which allow consolidation at low temperature, can be helpful. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Ajzenberg D.,University of Limoges
Expert Review of Anti-Infective Therapy | Year: 2011

Every 3 years, the International Congress on Congenital Toxoplasmosis meeting gathers experts with different backgrounds who are involved in congenital toxoplasmosis: gynecologists, pediatricians, ophthalmologists, microbiologists, epidemiologists and research scientists. Most attendees come from the Americas and Europe, where substantial work has been performed to better understand this disease. Two presentations that stressed major current issues in the field of toxoplasmosis are summarized here. © 2011 Expert Reviews Ltd.

Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2012-1.1.17. | Award Amount: 8.57M | Year: 2014

Solar Energy, as the primary source of renewable energy, will contribute a major part of this share, and its conversion by concentrating technologies for concentrating solar power (CSP) and heat generation has long been proven cost-effective for a wide range of applications. Several CSP projects have recently been put into operation. Some 2.400 MW are under construction and several GW are in advanced stages of planning, particularly in Spain, but also in other Southern European countries, like France, Greece and Portugal. In view of this challenge for research, development and application of concentrating solar systems involving a growing number of European industries and utilities in global business opportunities, the purpose of this project is to integrate, coordinate and further focus scientific collaboration among the leading European research institutions in solar concentrating systems that are the partners of this project and offer European research and industry access to the best-qualified research and test infrastructures. This proposal deals with the continuation of the successful SFERA, now looking for a closer approach to the European CSP industry.

Sepsis is defined as a systemic inflammatory response to infection, while severe sepsis (SS) is a sepsis complicated by acute organ dysfunction. Lung infections, in particular community-acquire pneumonia (CAP), are the leading cause of SS. The pathophysiologic mechanism of CAP-mediated SS is the complete dysregulation of the patients immune system. In an initial phase, the systemic hyperactivation of the host immune response against infection leads to high levels of inflammatory mediators, systemic vasodilatation, micro-vascular thrombosis and organ failure. In a second phase, the exaggerated activation of the immune response leads to a state of immunoparalysis, which is characterized by the occurrence of secondary, opportunistic infections. This makes CAP-mediated SS a life-threatening condition with mortality rates as high as 28-50%. The current standard of care (infection removal and control, functional support) does not improve the high mortality and, thus, CAP-mediated SS represents a major unmet medical need with a huge social burden. Therefore, treatments with the potential to modulate both the initial exacerbated immunoactivation and the subsequent immunosuppression are needed. Mesenchymal stem cells (MSCs), including adipose mesenchymal stem cells (ASCs), are known for their broad range of immunomodulatory properties, targeting multiple pro- and anti-inflammatory pathways, and possess antimicrobial capacities (releasing bactericidal peptides and promoting the phagocytosis by immune cells). Indeed, therapeutic benefit of MSC treatment in in vivo experimental models of sepsis has been extensively reported. The SEPCELL consortium believes that cell therapy with allogeneic ASCs may be an innovative therapeutic approach in order to re-establish the normal immune homeostasis of CAP-mediated SS patients, reducing organ injury and restoring organ functionality. A phase Ia/IIb clinical trial will be performed to test this possibility.

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