Possibility of a Double Well Potential in the Proton Bridge of Visual Pigments and Bacteriorhodopsin

The resonance Raman effect is examined in the case of vibrations which are governed by a double well potential. It is shown that in such a case the intensity of a resonance Raman line depends on three factors: the relative populations of the two wells in the . ground state and in the resonating electronic excited state and the displacement of the potential minima between the ground state and the excited state. Depending on the shapes of the potentials in the two states, the ground state populations might become unimportant as a factor determining intensities and the only observed Raman line might be due to the less populated well. It is suggested that such a situation is likely to exist for the proton bridge of the chromophore of visual pigments and bacteriorhodopsin, the Schiff bases of 11-cis and all-trans retinals respectively. This raises the question if resonance Raman spectra alone are capable of giving evidence of the extent of protonation of the chromophore in the ground state

Possibility of a Double Well Potential in the Proton Bridge of Visual Pigments and Bacteriorhodopsin

The resonance Raman effect is examined in the case of vibrations which are governed by a double well potential. It is shown that in such a case the intensity of a resonance Raman line depends on three factors: the relative populations of the two wells in the . ground state and in the resonating electronic excited state and the displacement of the potential minima between the ground state and the excited state. Depending on the shapes of the potentials in the two states, the ground state populations might become unimportant as a factor determining intensities and the only observed Raman line might be due to the less populated well. It is suggested that such a situation is likely to exist for the proton bridge of the chromophore of visual pigments and bacteriorhodopsin, the Schiff bases of 11-cis and all-trans retinals respectively. This raises the question if resonance Raman spectra alone are capable of giving evidence of the extent of protonation of the chromophore in the ground state

The E.A.T. Datascape: An Experiment in Digital Social History of Art

Experiments in Art and Technology (E.A.T.) is an organi- zation co-founded in 1966 by artists Robert Rauschenberg and Robert Whitman, and engineers Billy Klüver and Fred Waldhauer, in order to support collaboration between artists and engineers. The E.A.T. datascape is a digital instrument for analyzing the digitized traces left by its members via many available resources. Its aim is to study as closely as possible the complexity of collaborative interdisciplinary works. The E.A.T. datascape methodology makes it possible, by means of an anthropological action-centred approach, to go beyond the distinction between art history and art sociology and to renew the social history of art by challeng- ing the notion of authorship and by describing the work as constituted by the intersection between heterogeneous trajectories, rather than an object within a context that would influence it, or constitute its environment. In other words, it allows us to reflect on what digital design does, in turn, to the social history of art, and to put forward hypotheses about what a digital social history of art might be or could offer to the study of complex, interdisciplinary projects that are multiplying in the contemporary art world.Experiments in Art and Technology (E.A.T.) organizacija je koju su 1966. zajedno osnovali umjetnici Robert Rausch- enberg i Robert Whitman te inženjeri Billy Klüver i Fred Waldhauer, kako bi podržali suradnju između umjetnika i in- ženjera. E.A.T. datascape digitalni je instrument za analizu digitaliziranih tragova koje su ostavili članovi organizacije putem brojnih dostupnih resursa. Njegov je cilj što je mo- guće detaljnije analizirati složenost kolaborativnih inter- disciplinarnih radova. Zahvaljujući antropološkom pristupu usmjerenom na djelovanje, metodologija E.A.T datascapea omogućuje nadilaženje razlike između povijesti umjetnosti i sociologije umjetnosti te obnavljanje socijalne povijesti um- jetnosti dovođenjem u pitanje pojma autorstva i opisivanjem djela kao sačinjenoga presijecanjem heterogenih trajektorija, a ne kao objekta u kontekstu koji bi na njega utjecao ili tvo- rio njegovo okruženje. Drugim riječima, ona nam omogućuje razmišljanje o tome što digitalni dizajn čini zauzvrat za so- cijalnu povijest umjetnosti i iznošenje hipoteza o tome što bi digitalna socijalna povijest umjetnosti mogla biti ili što bi mogla ponuditi istraživanju složenih interdisciplinarnih pro- jekata, kojih je sve više u svijetu suvremene umjetnosti

The Experiments in Art and Technology Datascape

The Experiments in Art and Technology (E.A.T.) organization was set up in 1966 by the artists Robert Rauschenberg and Robert Whitman, in association with the engineers Billy Klüver and Fred Waldhauer. Its purpose was to facilitate collaboration between artists, engineers, and scientists by producing art systems and projects outside the art sphere in a strictly defined sense. Between 1966 and 1970, E.A.T. was thus at the root of more than 600 joint projects in the United States and abroad, mos..

Deux approches contrastées our développer les compétences transversales dans les grands groupes universitaires

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Interview with Jean-Paul Leclercq by Rémi Labrusse

Rémi Labrusse. Could you describe your career path as a researcher? How did it lead you to textiles? Jean-Paul Leclercq. From 1994 to 2006 I was curator of the collections of pre-1914 costumes and textiles at Les Arts décoratifs in Paris, and I took on the task of expanding them. Putting my advocacy for collaboration between museums into action, I drew up the dossier that enabled the Musée des Tissus in Lyon to acquire the 190 Grands livres de fabrique of the Lyon-based company Bianchini-Féri..

The E.A.T. Datascape: An Experiment in Digital Social History of Art

Experiments in Art and Technology (E.A.T.) organizacija je koju su 1966. zajedno osnovali umjetnici Robert Rauschenberg i Robert Whitman te inženjeri Billy Klüver i Fred Waldhauer, kako bi podržali suradnju između umjetnika i inženjera. E.A.T. datascape digitalni je instrument za analizu digitaliziranih tragova koje su ostavili članovi organizacije putem brojnih dostupnih resursa. Njegov je cilj što je moguće detaljnije analizirati složenost kolaborativnih interdisciplinarnih radova. Zahvaljujući antropološkom pristupu usmjerenom na djelovanje, metodologija E.A.T datascapea omogućuje nadilaženje razlike između povijesti umjetnosti i sociologije umjetnosti te obnavljanje socijalne povijesti umjetnosti dovođenjem u pitanje pojma autorstva i opisivanjem djela kao sačinjenoga presijecanjem heterogenih trajektorija, a ne kao objekta u kontekstu koji bi na njega utjecao ili tvorio njegovo okruženje. Drugim riječima, ona nam omogućuje razmišljanje o tome što digitalni dizajn čini zauzvrat za socijalnu povijest umjetnosti i iznošenje hipoteza o tome što bi digitalna socijalna povijest umjetnosti mogla biti ili što bi mogla ponuditi istraživanju složenih interdisciplinarnih projekata, kojih je sve više u svijetu suvremene umjetnosti.Experiments in Art and Technology (E.A.T.) is an organization co-founded in 1966 by artists Robert Rauschenberg and Robert Whitman, and engineers Billy Klüver and Fred Waldhauer, in order to support collaboration between artists and engineers. The E.A.T. datascape is a digital instrument for analyzing the digitized traces left by its members via many available resources. Its aim is to study as closely as possible the complexity of collaborative interdisciplinary works. The E.A.T. datascape methodology makes it possible, by means of an anthropological action-centred approach, to go beyond the distinction between art history and art sociology and to renew the social history of art by challenging the notion of authorship and by describing the work as constituted by the intersection between heterogeneous trajectories, rather than an object within a context that would influence it, or constitute its environment. In other words, it allows us to reflect on what digital design does, in turn, to the social history of art, and to put forward hypotheses about what a digital social history of art might be or could offer to the study of complex, interdisciplinary projects that are multiplying in the contemporary art world

Cellular pharmacokinetics of telavancin, a novel lipoglycopeptide antibiotic, and analysis of lysosomal changes in cultured eukaryotic cells (J774 mouse macrophages and rat embryonic fibroblasts)

Background Telavancin is a lipoglycopeptide with multiple mechanisms of action that include membrane-destabilizing effects towards bacterial cells. It shows bactericidal activity against forms of Staphylococcus aureus (phagolysosomal infection) with different resistance phenotypes [methicillin-resistant S. aureus, vancomycin-intermediate S. aureus or vancomycin-resistant S. aureus]. We examine here the uptake, efflux and intracellular distribution of telavancin in eukaryotic cells as well as its potential to induce lysosomal changes (in comparison with vancomycin and oritavancin). Methods J774 macrophages and rat embryo fibroblasts were exposed for up to 24 and 72 h to telavancin (5-90 mg/L). The following studies were performed: measurement of (14)C-labelled telavancin cellular uptake and subcellular distribution (cell fractionation), determination of pericellular membrane integrity (lactate dehydrogenase release), electron microscopy with morphometric analysis of changes in lysosome size and determination of total phospholipid and cholesterol content. Results The uptake of telavancin proceeded linearly as a function of time and concentration in both cell types (clearance rate of approximately 10 mL/g of protein/h). Efflux (macrophages) was approximately 5.7-fold slower. Telavancin subcellular distribution was superimposable on that of a lysosomal marker (N-acetyl-beta-hexosaminidase). It did not cause an increase in the release of lactate dehydrogenase and did not induce significant increases in total phospholipid or cholesterol content. It caused only mild morphological lysosomal alterations (similar to vancomycin and much less than oritavancin by morphometric analysis). Conclusions Telavancin is taken up by eukaryotic cells and localizes in lysosomes, causing mild morphological alterations without evidence of lipid metabolism alterations. These data support our observations that telavancin is active against intracellular S. aureus

Escherichia coli as Reservoir for Macrolide Resistance Genes

The plasmid-borne mph(A) gene that confers resistance to azithromycin and has recently emerged in Shigella sonnei is present in multidrug- and non–multidrug-resistant Escherichia coli isolates from 4 continents. Further spread of mph(A) to Shigella and Salmonella spp. may be expected