The Love's problem for hyperbolic thermoelasticity

In our paper we investigated the initial-boundary value problem for elastic layer situated on half space of another elastic medium. In this medium the thermomechanical interactions were taken into consideration. The system of equations with initial-boundary conditions describes the phenomenon of wave propagation with finite speed. In our problem there are two surfaces ie. free surface and contact surface between layer and half space. On the free surface are setting boundary conditions for normal and tangent surface force. We consider two types of contact between layer and half-space: rigid contact and slip contact. The initial-boundary value problem was solved by using integral transformations and Cagniard-de Hoope methods. From the solution of this problem follows that in layer and half space exist some kind of thermoelastic waves. We investigated moreover the conditions which should be fullfiled for propagation of Rayleigh and Love's type waves on the contact surface between layers and half space. The results obtained in our investigation were used in technical applications especially engineering design and diagnostics of roads and airfields. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Computational study of the mechanism of Bcl-2 apoptotic switch

In spite of attention devoted to molecular mechanisms of apoptosis, the details of functioning of one crucial component–the Bcl-2 apoptotic switch–are not completely understood. There are two competing mechanisms of its internal working—the indirect activation and the direct activation. In the absence of conclusive experimental data, we have used computational modeling to assess the properties of both mechanisms and their suitability to act as a biological switch. Since the two mechanisms form opposite poles of continuum of Bcl-2 molecular interaction models, we have constructed more general models including these two models as extreme cases. By studying the relationship between model parameters and the steady-state response we have found optimal interaction patterns which reproduce the behavior of the Bcl-2 apoptotic switch. Our results show, that stimulus–response ultrasensitivity is negatively affected by spontaneous activation of Bcl-2 effectors. We found that ultrasensitivity requires effectors activation, mediated by another subgroup of Bcl-2 proteins—activators. We have shown that the auto-activation of monomeric effector forms provides an ultrasensitivity enhancing feedback loop. Thorough robustness analysis revealed that the interaction pattern postulated in the direct activation hypothesis is able to conserve stimulus–response switching characteristics for wide range changes of its internal parameters. The robustness of the switch against the variation of the reaction parameter is strongly reduced for the intermediate hybrid model and even more for the indirect part of the models. Computer simulations of the more general model presented here suggest, that stimulus–response ultrasensitivity is an emergent property of the direct activation model that is unlikely to occur in the model of indirect activation. Introduction of indirect-model-specific interactions does not provide a better explanation of the Bcl-2 switch functionality compared to the direct model.     

Trace elemental analysis by laser-induced breakdown spectroscopy—Biological applications

Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. Since the late 1980s LIBS became visible in the analytical atomic spectroscopy scene; its applications having been developed continuously since then. In this paper, the use of LIBS for trace element determination in different matrices is reviewed. The main emphasis is on spatially resolved analysis of microbiological, plant and animal samples.     

Calculation of rotational barriers in amorphous polymers

The Monte Carlo method was used for generation of amorphous polyethylene configurations on a diamond lattice. Chain building was performed on the tetrahedral lattice of edges 36, 62 and 43 Å with periodic boundary conditions imposed.32 chains were generated, each with a length of 100 CH₂-groups (resulting density = 0.81 g·cm⁻³). Small spherical volumes with a radius of 10 Å were chosen at random from the total volume for the calculation of rotational barriers. The rotating bond was chosen to be close to the center of this sphere. We employed the method of molecular mechanics in order to calculate the rotational barriers. The calculation was made for 578 rotating bonds and the obtained distribution of rotational barriers is approximated by the corresponding Γ-distribution.     

Gas-Free Amino- and Alkoxycarbonylation of Aryl Iodides in a Bioinspired Deep Eutectic Solvent with Mo(CO)6 as a Safe CO Source

The Pd-catalyzed amino- and alkoxycarbonylation of aryl iodides has been exploited, for the first time, in a bioinspired Deep Eutectic Solvent and under gas-free conditions, by using Mo(CO)₆ as the CO source. The method allows for the preparation of carboxylic amides and esters in high yields (up to 99 %), short reaction time (2 h) and under mild reaction conditions (80 °C), with a low catalyst loading (2.5 mol %). Noteworthy, in the case of N-hexylbenzamide, it has been demonstrated that both the catalyst and DES can be used for four consecutive runs, with a moderate decrease of catalytic efficiency. The methodology has been also applied to the preparation of an Active Pharmaceutical Ingredient used for the treatment of human scabies and lice.     

Functional derivatives of sterically hindered amines. 1. Glycidyl compounds

Four polymerizable glycidyl derivatives of sterically hindered amines were prepared from derivatives of 2, 2, 6, 6-tetramethyl-4-hydroxypiperidine and 14, 16-dioxo-7, 15-diazadispiro [5, 1, 5, 3] hexadecane. One of them is a stable nitroxyl derivative.     

Azo‐group labelled polyesters by end‐capping with 2‐oxazoline derivatives – preparation

Two azobenzene containing 2‐oxazolines were used for labelling of polyesters with carboxylic end groups by the end‐capping method. The reaction proceeded under the conditions of reactive processing, and in a solution. High conversions in melt were achieved in several minutes. The coupling of the modifiers was proved by NMR spectroscopy.