Identification of short-chain poly-3-hydroxybutyrates in Saiga horn extracts using LC-MS/MS.

Saiga horn extracts were analyzed with the goal of obtaining new information about compounds present in it. The purpose of this study is to find synthetic alternatives to Saiga horn extract, which is used in traditional Chinese medicine, by identifying potentially biologically active compounds in the extracts. Using high-performance liquid chromatography coupled with high-resolution mass spectrometry, we have been able to identify a series of short-chain polyhydroxybutyrates in alcoholic extracts of Saiga horn. Optimized high-performance liquid chromatography coupled with tandem mass spectrometry methods for analysis of short-chain poly-3-hydroxybutyrates were developed and subsequently applied to investigate Saiga horn extract for the presence of these compounds, which might explain its biological actions, particularly for its antipyretic and procoagulant properties.

Interaction of surface plasmon polaritons and acoustic waves inside an acoustic cavity.

In this Letter, we introduce an approach for manipulation of active plasmon polaritons via acoustic waves at sub-terahertz frequency range. The acoustic structures considered are designed as phononic Fabry-Perot microresonators where mirrors are presented with an acoustic superlattice and the structure's surface, and a plasmonic grating is placed on top of the acoustic cavity so formed. It provides phonon localization in the vicinity of the plasmonic grating at frequencies within the phononic stop band enhancing phonon-light interaction. We consider phonon excitation by shining a femtosecond laser pulse on the plasmonic grating. Appropriate theoretical model was used to describe the acoustic process caused by the pump laser pulse in the GaAs/AlAs-based acoustic cavity with a gold grating on top. Strongest modulation is achieved upon excitation of propagating surface plasmon polaritons and hybridization of propagating and localized plasmons. The relative changes in the optical reflectivity of the structure are more than an order of magnitude higher than for the structure without the plasmonic film.

High-intensive femtosecond singular pulses in Kerr dielectrics.

The nonlinear dynamics of a high-power femtosecond singular pulse in Kerr media are analyzed numerically upon optically induced ionization. We examine the plasma inertia impact to stable propagation of optical vortices. Multifoci behavior of vortices in medium are revealed. Next we numerically demonstrate that inertial character of plasma formation provides a quasi-soliton regime of vortex propagation resistant to symmetry-breaking perturbation.

Study of saiga horn using high-performance liquid chromatography with mass spectrometry.

The saiga horns have been investigated the using of modern analytic methods. High-performance liquid chromatography (HPLC) with mass-spectrometric (MS and MS/MS) detection and polyacrylamide gel electrophoresis (PAGE) were used. It could be concluded that basic proteins of the saiga horns are keratins and collagen. The basic representation protein in all samples is keratin type I microfibrillar (from sheep), keratin type II microfibrillar (from sheep), collagen type I (α(1)) (from bovine) and collagen type I (α(2)) (from bovine). Free amino acids we determined in all samples are nontreated by enzyme.

Efficient 3D numerical approach for temperature prediction in laser irradiated biological tissues.

Temperature prediction in biological tissues irradiated by an optical source is frequently required in some medical applications, like Thermotherapy, Hyperthermia or tissue ablation. In this work we propose a new numerical approach to solve the bio-heat equation. It is based on the two steps 3D modified Du Fort-Frankel algorithm, which allows a better convergence, more accuracy and a faster computation than previous numerical methods developed by other authors. The model also includes adaptive spatial mesh and time step refinement. These improved results for opto-thermal temperature distribution could be used for choosing appropriate laser treatment parameters in medical praxis.