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Chirality selective spin interactions mediated by the moving superconducting condensate
2018
We show that superconducting correlations in the presence of nonzero condensate velocity can mediate the peculiar interaction between localized spins that breaks the global inversion symmetry of magnetic moments. The proposed interaction mechanism is capable of removing fundamental degeneracies between topologically distinct magnetic textures. For the generic system of three magnetic impurities in the current-carrying superconductor, we find the energy term proportional to spin chirality. In realistic superconductor/ferromagnetic/superconductor setups we reveal significant energy differences between various magnetic textures with opposite chiralities. We calculate Josephson energies of junc…
Supramolecular Organocatalysis in Water Mediated by Macrocyclic Compounds
2018
In the last decades many efforts have been devoted to design supramolecular organocatalysts able to work in water as the reaction medium. The use of water as solvent provides promising benefits with respect to environmental impact. In this context, macrocyclic compounds played a role of primary importance thanks to their ease of synthesis and their molecular recognition abilities toward the reactants. The aim of this review is to give an overview of the recent advances in the field of supramolecular organocatalysis in water, focusing the attention on calixarene and cyclodextrins derivatives. Calixarenes and cyclodextrins, thanks to their hydrophobic cavities, are able to host selectively th…
Scattering of Co-Current Surface Waves on an Analogue Black Hole
2018
We report on what is to our knowledge the first scattering experiment of surface waves on an accelerating transcritical flow, which in the analogue gravity context is described by an effective spacetime with a black-hole horizon. This spacetime has been probed by an incident co-current wave, which partially scatters into an outgoing countercurrent wave on each side of the horizon. The measured scattering amplitudes are compatible with the predictions of the hydrodynamical theory, where the kinematical description in terms of the effective metric is exact.
Proximal versus distal contextual factors: which impact on meal pleasure and food intake in the elderly living in a nursing home?
2014
Poster présenté lors de la conférence; Introduction: Several authors pointed out the importance of meal context on food intake in nursing home. Some authors assessed the impact of context improvement on food intake in nursing home, but they assessed ‘holistic’ strategies by improving physical environment, increasing choice level, changing staff organization… (Abbott et al. 2013). Despite some of these interventions were effective, these strategies are costly and thus difficult to be implemented in nursing home. The aim of the present experiment was to assess the impact of single contextual factors, three proximal factors (food contextual factors) and three distal factors (non-food contextua…
OUR MOTHER OF THE WOODS. A CONTRIBUTION TO THE STUDY OF THE "MADONNAS OF THE TREES" IN THE EURO-MEDITERRANEAN AREA
2016
Looking at the Madonnas of the trees, we see how an anthropologist disregarding historical depth renounces an integral vision of reality by which it can be measured and interpreted, giving rise «to sometimes narrow, sometimes even grotesque results; with an unexpected resurrection, however, of a banally sociological perspective, in many cases hidden under the false pretences of social anthropology». The effects of such a surrender are particularly evident when we explore the symbolic dimension. In fact, a purely synchronic approach proves to be totally inadequate: «research can be restored its critical depth and substance by paying attention to the processes of construction of meaning and t…
Physics meets Bohemia Einstein in Bohemia Michael D. Gordin Princeton University Press, 2020. 360 pp.
2020
In Einstein in Bohemia, Michael Gordin seeks to illuminate the elusive significance of Einstein9s brief tenure in Prague, both for the biography of the famous physicist and for the cultural history of Bohemia. An expert in the history of modern physical sciences and of Russian, European, and American history, Gordin pulls together a wealth of information about the wider context of Einstein9s stay in Prague and of the cultural, scientific, and political history of Bohemia.
Stealth dicing with Bessel beams and beyond
2016
In the context of laser cutting of transparent materials, we investigate glass cleaving with Bessel beams and report that a modification of the beam with 3 main lobes drastically enhances cleavability and reduces defects.
Characteristics of Mesozoic fluvio-lacustrine formations of the western Central African Republic (Carnot Sandstones) by means of mineralogical and ex…
1990
Abstract The so-called Carnot Sandstones, Mesozoic fluvio-lacustrine detrital formation, which stretch over an area of more than 40 000 km 2 in the western part of the Central African Republic, are made of a succession of conglomerates, sandstones and argilites which can reach 300 m in thickness. Heavy mineral analyses and quartz exoscopic studies of this detrital material allow to understand the geology of these formations. The detrital material origin: heavy mineral distribution in the lower levels indicates mostly a meridional origin with a quantitatively poor peripheral supply. The importance of the transport: quartz exoscopic observations show that the main part of the detrital materia…
ChemInform Abstract: Magnetic Exchange Between Metal Ions with Unquenched Orbital Angular Momenta: Basic Concepts and Relevance to Molecular Magnetism
2010
This review article is a first attempt to give a systematic and comprehensive description (in the framework of the unified theoretical approach) of the exchange interactions in polynuclear systems based on orbitally degenerate metal ions in the context of their relevance to the modern molecular magnetism. Interest in these systems is related to the fundamental problems of magnetism and at the same time steered by a number of impressive potential applications of molecular magnets, like high-density memory storage units, nanoscale qubits, spintronics and photoswitchable devices. In the presence of orbital degeneracy, the conventional spin Hamiltonian (Heisenberg–Dirac–van Vleck model) becomes…
Fluorinated heterocyclic compounds: an assay on the photochemistry of some fluorinated 1-oxa-2-azoles: an expedient route to fluorinated heterocycles
2004
Abstract Photoinduced heterocyclic rearrangements of ON bond-containing azoles have been claimed in the synthesis of target fluorinated heterocyclic compounds. In this context, the photochemical behavior of some fluorinated 1,2,4-oxadiazoles has been investigated. Irradiations of 3-amino-5-perfluoroalkyl-1,2,4-oxadiazoles at λ =313 nm in methanol gave open-chain products arising from a reaction of the nucleophilic solvent with either the first formed ring-photolytic species or with a nitrilimine moiety generated from it. Differently, irradiations in methanol with the presence of triethylamine (TEA) followed competing phototransposition pathways leading to the ring-isomers 2-amino-5-perfluo…