Advances in surface plasmon resonance-based high throughput biochips

This article reviews our recent advances in surface plasmon resonance (SPR) based biochips. It includes four issues, which are the preparation and characterization of high quality gold film, the preparation and characterization of self-assembled monolayer (SAM), dynamics of DNA adsorption on SAMs, and SPRbased microscopies. Numerous topics related to SPR, such as, the modeling of SPR by transmission matrix, effective medium theory, applications of SPR in biology, and SPR-based novel microscopies, are discussed. A novel electrochemical technique, which is extremely useful for the preparation and characterization of high quality SAMs, is also discussed.     

Representation theory of generalized deformed oscillator algebras

The representation theory of the generalized deformed oscillator algebras (GDOA's) is developed. GDOA's are generated by the four operators {1, a, a , N}. Their commutators and Hermiticity properties are those of the boson oscillator algebra, except for [a, a ] _q = G(N), where [a, b] _q = ab – q ba and G(N) is a Hermitian, analytic function. The unitary irreductible representations are obtained by means of a Casimir operator C and the semi-positive operator a a. They may belong to one out of four classes: bounded from below (BFB), bounded from above (BFA), finite-dimentional (FD), unbounded (UB). Some examples of these different types of unirreps are given.     

Experimental implementation of a concatenated quantum error-correcting code

Concatenated coding provides a general strategy to achieve the desired level of noise protection in quantum information processing. We report the implementation of a concatenated quantum error-correcting code able to correct phase errors with a strong correlated component. The experiment was performed using liquid-state nuclear magnetic resonance techniques on a four spin subsystem of labeled crotonic acid. Our results show that concatenation between active and passive quantum error correction is a practical tool to handle realistic noise involving both independent and correlated errors.     

Sonochemical degradation of triclosan in water and wastewater

The sonochemical degradation of 5 μg l⁻¹ triclosan, a priority micro-pollutant, in various environmental samples (seawater, urban runoff and influent domestic wastewater) as well as in model solutions (pure and saline water) was investigated. Experiments were conducted with a horn-type sonicator operating at 80 kHz frequency and a nominal applied power of 135 W, while solid-phase microextraction coupled with gas chromatography–electron capture detector (SPME/GC–ECD) was employed to monitor triclosan degradation. The latter followed pseudo-first order kinetics with the rate constant being (min⁻¹): 0.2284 for seawater > 0.1051 for 3.5% NaCl in deionised water > 0.0597 for centrifuged urban runoff  0.0523 for untreated urban runoff > 0.0272 for deionised water > 0.0063 for wastewater influent. SPME/GC–ECD and SPME coupled with gas chromatography–mass spectrometry (SPME/GC–MS) were also used to check for the formation of chlorinated and other toxic by-products; at the conditions in question, the presence of such compounds was not confirmed.     

Noise induced state transitions, intermittency, and universality in the noisy Kuramoto-Sivashinksy equation

Consider the effect of pure additive noise on the long-time dynamics of the noisy Kuramoto-Sivashinsky (KS) equation close to the instability onset. When the noise acts only on the first stable mode (highly degenerate), the KS solution undergoes several state transitions, including critical on-off intermittency and stabilized states, as the noise strength increases. Similar results are obtained with the Burgers equation. Such noise-induced transitions are completely characterized through critical exponents, obtaining the same universality class for both equations, and rigorously explained using multiscale techniques.     

Nonstationary wave turbulence in an elastic plate

We report experimental results on the decay of wave turbulence in an elastic plate obtained by stopping the forcing from a stationary turbulent state. In the stationary case, the forcing is seen to induce some anisotropy and a spectrum in disagreement with the weak turbulence theory. After stopping the forcing, almost perfect isotropy is restored. The decay of energy is self-similar and the observed decaying spectrum is in better agreement with the prediction of the weak turbulence theory. The dissipative part of the spectrum is partially consistent with the theoretical prediction based on previous work by Kolmakov. This suggests that the nonagreement with the weak turbulence theory is mostly due to a spurious effect of the forcing related to the finite size of the system.     

Spin-spin coupling edition in chiral liquid crystal NMR solvent

The application of the G-SERFph pulse sequence is presented on enantiomeric mixtures dissolved in a chiral liquid crystal. It aims at editing, within one single 2D spectrum, every proton coupling which is experienced by a given proton site in the molecule, and leads to real phased T-edited spectroscopy (T=J+2D). This NMR experiment is based on the combination of homonuclear semi-selective refocusing techniques with a spatial frequency encoding of the sample. This approach, which consists in handling selectively each coupling in separate cross sections of the sample, is applied to the visualization of enantiomers dissolved in a chiral liquid crystalline phase. Advantages and limits of this methodology are widely discussed.     

Long range one-dimensional ordering of lead phthalocyanine monolayer on InSb(1 0 0) (4 × 2)/c(8 × 2)

Sub-monolayer and monolayer of lead phthalocyanine deposited on InSb(1 0 0) (4 × 2)/c(8 × 2) surface have been investigated by scanning tunneling microscopy and low energy electron diffraction. Molecules first adsorb on the indium rows of the (4 × 2)/c(8 × 2) structure in the [1 1 0] direction and diffuse at the surface in order to form two-dimensional islands. The molecule-substrate interaction stabilizes the PbPc molecules on the In rows. It weakens the interaction between molecules located in adjacent rows resulting in numerous gliding planes between the molecular chains, in the direction parallel to the rows. At monolayer completion, a long-range one-dimensional order is adopted by the molecules in the [1 1 0] direction.     

Tensor Gauge Fields in Arbitrary Representations of GL(D, ℝ). Duality and Poincaré Lemma

Using a mathematical framework which provides a generalization of the de Rham complex (well-designed for p-form gauge fields), we have studied the gauge structure and duality properties of theories for free gauge fields transforming in arbitrary irreducible representations of GL(D, ). We have proven a generalization of the Poincaré lemma which enables us to solve the above-mentioned problems in a systematic and unified way.