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Mutations in hepatitis C virus RNAs conferring cell culture adaptation.
2001
ABSTRACT As an initial approach to studying the molecular replication mechanisms of hepatitis C virus (HCV), a major causative agent of acute and chronic liver disease, we have recently developed selectable self-replicating RNAs. These replicons lacked the region encoding the structural proteins and instead carried the gene encoding the neomycin phosphotransferase. Although the replication levels of these RNAs within selected cells were high, the number of G418-resistant colonies was reproducibly low. In a search for the reason, we performed a detailed analysis of replicating HCV RNAs and identified several adaptive mutations enhancing the efficiency of colony formation by several orders of…
p -Type and n -type conductometric behaviors of octachloro-metallophthalocyanine-based heterojunctions, the key role of the metal
2020
In the present work, we determined the electrical properties of octachlorinated metallophthalocyanines with Co(II) and Cu(II) ions as metal centers. We engaged them in heterojunctions, with lutetium bisphthalocyanine as a partner. Surprisingly, cobalt and copper complexes show opposite behaviors, the first being an [Formula: see text]-type material whereas the latter is a [Formula: see text]-type material, as deduced from the response of the heterojunctions towards ammonia; showing the unusual key role played by the metal center. While the LuPc[Formula: see text]/Cu(Cl[Formula: see text]Pc) complex exhibits a negative response to ammonia, the LuPc[Formula: see text]/Co(Cl[Formula: see text…
Atmospheric pressure plasma polymerisation of metalloporphyrins containing mesoporous membranes for gas sensing applications
2013
Abstract Metalloporphyrins are embedded in an organosilicon matrix by an easily up-scalable atmospheric pressure dielectric barrier discharge method. The integrity of the metalloporphyrins, followed by UV–visible spectroscopy, is successfully preserved and their aggregation prevented. The single molecule properties, rather than the bulk ones, are thus enhanced. Exposure to triethylamine, which reaches the metalloporphyrins through the pores of the organosilicon membrane, led to a shift in the absorption spectrum and confirms the gas sensing potential of such coatings.
LOFT - A large observatory for x-ray timing
2010
The high time resolution observations of the X-ray sky hold the key to a number of diagnostics of fundamental physics, some of which are unaccessible to other types of investigations, such as those based on imaging and spectroscopy. Revealing strong gravitational field effects, measuring the mass and spin of black holes and the equation of state of ultradense matter are among the goals of such observations. At present prospects for future, non-focused X-ray timing experiments following the exciting age of RXTE/PCA are uncertain. Technological limitations are unavoidably faced in the conception and development of experiments with effective area of several square meters, as needed in order to…
High-Speed Machines: Typologies, Standards, and Operation under PWM Supply
2018
This paper presents an overview of the most recent state of the art in the field of high-speed electric machines fed through high-frequency converters. This type of systems is rapidly wide spreading in aeronautical and automotive applications, as well as microturbines. Each typology has its own advantages and downsides, which are analytically presented in this paper. Some types of high-speed electric machines require high-frequency voltage supply, highly stressing the dielectric materials of the winding insulation system. For this reason, in high-speed electric drives, premature failure may occur and a reduction of the total system reliability has been observed in the past years. Such issue…
Brevi note ornitologiche dalla Sicilia occidentale
1998
Ornithological short notes from western Sicily (Italy)
The Word in the Image: an Epiconographic Analysis of Reformed Mosaics in Rome (Twelfth-century)
2011
International audience
Souffrir en musique
1994
Suffering to Music - Although, in its relation to suffering, music is generally reputed for possessing therapeutic virtues, several iconographie and written sources dating from the thirteenth to the fifteenth centuries attribute a harmful influence to music. This ambivalence was based on the correlation between the intensity of suffering and that of the sonorous quality of musical instruments, which in the Middle Ages were divided into two great families in accordance to the sound volume they produced. Consequently it was according to their high and strident or low and soft sonorities that the instruments were thought to act on suffering, either amplifying it or alleviating it.
Expériences religieuses et chemins de perfection dans l'Occident médiéval. Études offertes à André Vauchez par ses élèves
2012
En hommage à leur maître dont l'œuvre scientifique a profondément renouvelé l'histoire du christianisme occidental au Moyen Âge, les élèves d'André VAUCHEZ, membre de l'Académie, ont souhaité lui offrir les 24 études rassemblées dans ce volume. Ancrées aux grands axes de la réflexion qu'il leur a transmise et qu'ils ont à leur tour développée, celles-ci se regroupent en cinq thèmes, au fil desquels se déploient des expériences spirituelles qui furent autant de quêtes de perfection. L'ouverture de Jean DELUMEAU, membre de l'AIBL, dédiée au retable de l'Agneau mystique des frères Van Eyck introduit un premier ensemble de textes consacrés à l'hagiographie et à la sainteté, prolongés par une ex…
Bioactive and biodegradable silica biomaterial for bone regeneration.
2014
Biosilica, a biocompatible, natural inorganic polymer that is formed by an enzymatic, silicatein-mediated reaction in siliceous sponges to build up their inorganic skeleton, has been shown to be morphogenetically active and to induce mineralization of human osteoblast-like cells (SaOS-2) in vitro. In the present study, we prepared beads (microspheres) by encapsulation of β-tricalcium phosphate [β-TCP], either alone (control) or supplemented with silica or silicatein, into the biodegradable copolymer poly(d,l-lactide-co-glycolide) [PLGA]. Under the conditions used, ≈5% β-TCP, ≈9% silica, and 0.32μg/mg of silicatein were entrapped into the PLGA microspheres (diameter≈800μm). Determination of …