801 research outputs found
One and two-photon photocurrents from tunable organic microcavity photodiodes
Journal ArticleWe have constructed multilayer thin-film organic microcavity photodiodes with the photoactive layer comprised of a spin-coated conjugated polymer and an evaporated C60 layer. The electrodes are designed as semitransparent mirrors which form a resonant cavity structure. The photocurrent spectra show distinct maxima at the optical resonances of the cavities, which are located up to 200 nm below the fundamental optical transition of the polymer. The design allows a simple tuning of the spectral response by varying the layer thickness. Microcavity photodiodes are also shown to be highly sensitive two-photon detectors, which exhibit a factor 500 improvement in the two-photon response compared to devices without photonic confinement
Dynamical and quasistatic structural relaxation paths in Pd_(40)Ni_(40)P_(20) glass
By sequential heat treatment of a Pd_(40)Ni_(40)P_(20) metallic glass at temperatures and durations for which
Ī±-relaxation is not possible, dynamic, and quasistatic relaxation paths below the glass transition are
identified via ex situ ultrasonic measurements following each heat treatment. The dynamic
relaxation paths are associated with hopping between nonequilibrium potential energy states of the
glass, while the quasistatic relaxation path is associated with reversible Ī²-relaxation events toward
quasiequilibrium states. These quasiequilibrium states are identified with secondary potential energy
minima that exist within the inherent energy minimum of the glass, thereby supporting the concept
of the sub-basin/metabasin organization of the potential-energy landscape
Virus-like glycodendrinanoparticles displaying quasi-equivalent nested polyvalency upon glycoprotein platforms potently block viral infection
Ligand polyvalency is a powerful modulator of proteināreceptor interactions. Hostāpathogen infection interactions are often mediated by glycan ligandāprotein interactions, yet its interrogation with very high copy number ligands has been limited to heterogenous systems. Here we report that through the use of nested layers of multivalency we are able to assemble the most highly valent glycodendrimeric constructs yet seen (bearing up to 1,620 glycans). These constructs are pure and well-defined single entities that at diameters of up to 32ānm are capable of mimicking pathogens both in size and in their highly glycosylated surfaces. Through this mimicry these glyco-dendri-protein-nano-particles are capable of blocking (at picomolar concentrations) a model of the infection of T-lymphocytes and human dendritic cells by Ebola virus. The high associated polyvalency effects (Ī²>106, Ī²/N ~102ā103) displayed on an unprecedented surface area by precise clusters suggest a general strategy for modulation of such interactions.EspaƱa MICINN CTQ2008-01694EspaƱa MICINN CTQ2011-2341
Imaging butyrylcholinesterase activity in Alzheimer's disease
No abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55890/1/21023_ftp.pd
Microscopic Model for Granular Stratification and Segregation
We study segregation and stratification of mixtures of grains differing in
size, shape and material properties poured in two-dimensional silos using a
microscopic lattice model for surface flows of grains. The model incorporates
the dissipation of energy in collisions between rolling and static grains and
an energy barrier describing the geometrical asperities of the grains. We study
the phase diagram of the different morphologies predicted by the model as a
function of the two parameters. We find regions of segregation and
stratification, in agreement with experimental finding, as well as a region of
total mixing.Comment: 4 pages, 7 figures, http://polymer.bu.edu/~hmakse/Home.htm
Assessment of the biodistribution of an [ 18 F]FDGāloaded perfluorocarbon double emulsion using dynamic microāPET in rats
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97497/1/cmmi1532.pd
Piiiā37
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109838/1/cptclpt2006257.pd
[ 11 C]NNC 12-0722 or [ 18 F]GBR 13119: Just what is ābetterā?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46836/1/259_2004_Article_BF00285593.pd
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