Photopolymerization of mixed monolayers and black lipid membranes containing gramicidin A and diacetylenic phospholipids

We formed monolayers and black lipid membranes (BLMs) of photopolymerizable lipids mixed with the channel-forming protein gramicidin A to evaluate their miscibility and the potential for improved stability of the BLM scaffold through polymerization. Analyses of surface pressure vs area isotherms indicated that gramicidin A dispersed with three different synthetic, polymerizable, diacetylene-containing phospholipids, 1,2-di-10,12-tricosadiynoyl-sn-glycero-3-phosphocholine (DTPC), 1,2-di-10,12-tricosadiynoyl-sn-glycero-3-phosphoethanolamine (DTPE), and 1-palmitoyl-2,10,12-tricosadiynoyl-sn-glycero-3-phosphoethanolamine (PTPE) to form mixed monolayers at the air-water interface on a Langmuir-Blodgett (LB) trough. Conductance measurements across a diacetylenic lipid-containing BLM confirmed dispersion of the gramicidin channel with the lipid layer and demonstrated gramicidin ion-channel activity before and after UV exposure. Polymerization kinetics of the diacetylenic films were monitored by film pressure changes at constant LB trough area and by UV-vis absorption spectroscopy of polymerized monolayers deposited onto quartz. An initial increase in film pressure of both the pure diacetylene lipid monolayers and mixed films upon exposure to UV light indicated a change in the film structure. Over the time scale of the pressure increase, an absorbance peak indicative of polymerization evolved, suggesting that the structural change in the lipid monolayer was due to polymerization. Film pressure and absorbance kinetics also revealed degradation of the polymerized chains at long exposure times, indicating an optimum time of UV irradiation for maximized polymerization in the lipid layer. Accordingly, exposure of polymerizable lipid-containing black lipid membranes to short increments of UV light led to an increase in the bilayer lifetime.     

Measurement of time-dependent CP-violating parameters in B(0)-->K_(S)(0)K_(S)(0) decays

We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst).     

Time-dependent CP-violating asymmetry in B0-->rho0gamma decays

We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively.     

Synthesizing chaotic maps with prescribed invariant densities

The Inverse Frobenius–Perron Problem (IFPP) concerns the creation of discrete chaotic mappings with arbitrary invariant densities. In this Letter, we present a new and elegant solution to the IFPP, based on positive matrix theory. Our method allows chaotic maps with arbitrary piecewise-constant invariant densities, and with arbitrary mixing properties, to be synthesized.     

Measurement of the near-threshold e+e- --> D(*)+/-D(*)-/+ cross section using initial-state radiation

We report a measurement of the exclusive e+e- -->D(*)+/-D*-/+ cross section as a function of center-of-mass energy near the D(*)+/-D*-/+ threshold with initial-state radiation. A partial reconstruction technique is used to increase the efficiency and to suppress background. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 547.8 fb(-1).     

Measurement of the e+e- -->pi+pi- J/psi cross section via initial-state radiation at Belle

The cross section for e(+)e(-)-->pi(+)pi(-)J/psi between 3.8 and 5.5 GeV/c(2) is measured using a 548 fb(-1) data sample collected on or near the Upsilon(4S) resonance with the Belle detector at KEKB. A peak near 4.25 GeV/c(2), corresponding to the so called Y(4260), is observed. In addition, there is another cluster of events at around 4.05 GeV/c(2). A fit using two interfering Breit-Wigner shapes describes the data better than one that uses only the Y(4260), especially for the lower-mass side of the 4.25 GeV enhancement.     

Asymptotically (in)dependent multivariate maxima of moving maxima processes

Smith and Weissman introduced a M4 class of processes which are very flexible models for temporally dependent multivariate extreme value processes. However all variables in these M4 models are asymptotically dependent and what this paper does is to extend this M4 class in a number of ways to produce classes of models which are also asymptotically independent. We shall study properties of the proposed models. In particular, asymptotic dependence indexes, coefficients of tail dependence, and extremal indexes are derived for each case.     

The formation and evolution of fractal structure within chaotic attractors

In this paper we examine in detail the formation and evolution of fractal structure in the chaotic attractors of nonlinear dynamical systems. We explicitly obtain the fractal structure of the underlying chaotic attractors of low-dimensional systems and study their evolution as a system parameter is varied. Using periodic enumeration, dimensional, andf() spectral techniques, we obtain a detailed characterization of the multifractal structure.     

Extraordinary atomic mobility of Au{111} at 80 Kelvin: effect of styrene adsorption

We describe how the presence of styrene, a weakly adsorbed molecule, dramatically restructures the Au{111} surface at temperatures as low as 80 K. The restructuring manifests itself both in mobility of step-edge atoms, as well as changes in the position of the herringbone reconstruction over time. These effects are explained in terms of the preferential adsorption sites of styrene allowing it to assist in atom detachment from step edges, as well as lowering of the energetic barrier for movement of the herringbone reconstruction. This work has important consequences for studies in which Au is used as a support for or as an electrical contact to molecules.     

Characterization of chaos

We give a brief introduction to chaos and its characterization. We examine some standard systems in detail from the perspective of chaos and review their properties. Concepts necessary to understand them, such as dimension, are also reviewed. To illustrate the main ideas, we choose three examples which have served as paradigms for the study of chaos in physical systems, namely, the Hénon discrete mapping, the Lorenz system of coupled ordinary differential equations, and the Mackey-Glass infinite-dimensional delay differential equation.