Interaction-induced dynamical phase locking of Bose-Einstein condensates

We show that interactions result in the emergence of a {\it definite} relative-phase between two initially incoherent Bose-Einstein condensates. The many-realization interference fringe visibility is universal at $g_{12}^{(1)}\sim1/3$ throughout the Josephson interaction regime, as evident from a semiclassical picture. Other types of incoherent preparation yield qualitatively different coherence dynamics.Comment: 4 pages, 5 figure

Entropy exchange and entanglement in the Jaynes-Cummings model

The Jaynes-Cummings model is the simplest fully quantum model that describes the interaction between light and matter. We extend a previous analysis by Phoenix and Knight (S. J. D. Phoenix, P. L. Knight, Annals of Physics 186, 381). of the JCM by considering mixed states of both the light and matter. We present examples of qualitatively different entropic correlations. In particular, we explore the regime of entropy exchange between light and matter, i.e. where the rate of change of the two are anti-correlated. This behavior contrasts with the case of pure light-matter states in which the rate of change of the two entropies are positively correlated and in fact identical. We give an analytical derivation of the anti-correlation phenomenon and discuss the regime of its validity. Finally, we show a strong correlation between the region of the Bloch sphere characterized by entropy exchange and that characterized by minimal entanglement as measured by the negative eigenvalues of the partially transposed density matrix.Comment: 8 pages, 5 figure

Single-Molecule Fluorescence Detection of a Synthetic Heparan Sulfate Disaccharide

The first single-molecule fluorescence detection of a structurally-defined synthetic carbohydrate is reported: a heparan sulfate (HS) disaccharide fragment labeled with Alexa488. Single molecules have been measured whilst freely diffusing in solution and controlled encapsulation in surface-tethered lipid vesicles has allowed extended observations of carbohydrate molecules down to the single-molecule level. The diverse and dynamic nature of HS–protein interactions means that new tools to investigate pure HS fragments at the molecular level would significantly enhance our understanding of HS. This work is a proof-of-principle demonstration of the feasibility of single-molecule studies of synthetic carbohydrates which offers a new approach to the study of pure glycosaminoglycan (GAG) fragments

Hemorrhagic infarct of basal ganglia in cardiac arrest. CT and MRI findings. 2 cases

We report the CT and MRI findings in two cases of hemorrhagic infarct of the basal ganglia (BG), following out-of-hospital cardiac arrest (CA). In case 1, Brain-CT realized at day 2 showed bilateral and almost symmetric hemorrhagic infarct of the BG and infarct of the tectum of the mesencephalon. In case 2, MRI realized at day 6 showed hemorrhagic infarct of both lenticular nuclei on T2 GE images. In both cases there was no medical history and the cardiovascular and the coagulation profile were normal. In these cases, the lesions are observed earlier than reported in a few previous radiological cases. Similar lesions have been reported in pathological studies. These lesions seem occur early after CA. Reperfusion is probably responsible for the hemorrhagic transformation. The reason why some patients present either BG or brainstem infarct or both remains unclear. Bilateral and symmetric hemorrhagic infarct of the BG, especially of the Lenticular nuclei, and infarct of the dorsal pons and mesencephalic tegmentum seem to be a characteristic feature of profound and prolonged hypotension or of CA

Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering

We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely-polarized 3 GeV electrons from unpolarized protons at Q^2 = 0.15, 0.25 (GeV/c)^2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state, and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A_n provides a direct probe of the imaginary component of the 2-gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.Comment: 5 pages, 3 figures, submitted to Physical Review Letters; shortened to meet PRL length limit, clarified some text after referee's comment