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The paper presents an original approach to time-domain reflectance fluorescence molecular tomography (FMT) of small animals. It is based on the use of early arriving photons and state-of-the-art compressed-sensing-like reconstruction algorithms and aims to improve the spatial resolution of fluorescent images. We deduce the fundamental equation that models the imaging operator and derive analytical representations for the sensitivity functions which are responsible for the reconstruction of the fluorophore absorption coefficient. The idea of fluorescence lifetime tomography with our approach is also discussed. We conduct a numerical experiment on 3D reconstruction of box phantoms with spherical fluorescent inclusions of small diameters. For modeling measurement data and constructing the sensitivity matrix we assume a virtual fluorescence tomograph with a scanning fiber probe that illuminates and collects light in reflectance geometry. It provides for large source-receiver separations which correspond to the macroscopic regime. Two compressed-sensing-like reconstruction algorithms are used to solve the inverse problem. These are the algebraic reconstruction technique with total variation regularization and our modification of the fast iterative shrinkage-thresholding algorithm. Results of our numerical experiment show that our approach is capable of achieving as good spatial resolution as 0.2 mm and even better at depths to 9 mm inclusive.

The fracture energy of 12Cr1MoV steel specimen with V-shaped, U-shaped and I-shaped notches under impact loading was measured and analysed. The results were described using three common approaches to ductile-brittle fracture: force-based, energy-based and strain-based. Within the stage-wise approach of physical mesomechanics of materials, the rate of increase/decrease of load at the stage of initiation and propagation of a macroscopic defect was evaluated, providing a good correlation with the work of fracture. The excitable cellular automata technique was applied to simulate the deformational behaviour of the specimens with different shape of notches. It was demonstrated that in the case of the blunted notch, the maximum impact toughness is facilitated by a more uniform distribution of the load along the notch, which hinders brittle fracture at lower testing temperature. For the specimen with the sharp I-notch, the bands of localised shear are oriented normally to the loading axis, inhibiting macroscopic localisation of strain and crack propagation. For this reason, the impact toughness of the specimen with the I-notch appeared to be higher than that of the V-notched one. Using the fractographic analysis and the size of shear lips as a quantitative fracture parameter, a physical-mechanistic scheme of fracture was suggested for the case of enhanced localised plasticity near the stress riser.

Impact loading curves and fracture energy of the notched 12Cr1MoV ductile steel specimens are analysed. The qualitative description and quantitative parameters are obtained for major stages of ductile and brittle fracture depending on the shape of the notch and the stress stiffness ahead. It was shown that a zone with enhanced plasticity forms in the vicinity of V-, U- and I-shaped notches at 20 °C testing temperature, giving rise to ductile fracture. The stress stiffness at the notch tip increased with testing temperature reduced to −40 °C. We demonstrated that the size of shear lips on a fracture surface is a quantitative characteristic of fracture. Using this approach, which is close by nature to non-linear fracture mechanics, together with the quantitative description of fracture surfaces, a physical–mechanical scheme of the specimen fracture was suggested for the case of enhanced and localized (constrained) plasticity near the stress concentrator tip.

Intermediates (III) are isolable solids which are used without purification for the following thermal rearrangement.

The morbidity of tick-borne encephalitis (TBE) varies yearly by as much as 10-fold among the people of Western Siberia. This long-term variation is dependent on many factors such as the density of the tick populations, the prevalence of TBE virus (TBEV) among sub-adult ticks, the yearly virulence of the TBEV, and prophylactic measures. Here we highlight the role of small mammal hosts in the circulation of TBEV through the ecosystem. Refining classical models of non-viremic horizontal transmission, we emphasize the recently understood fact that the physiological and immunological status of the small mammal hosts affects the tick and virus-host interactions. In addition to its theoretical interest, our approach may lead to some practical improvements in the precision of epidemiological forecasts and perhaps in forestalling the severity of outbreaks of TBE, or, at least, in forewarning medical authorities and the general public of impending TBE outbreaks.

The origin of the reinforcement effect in uniaxially drawn films on the basis of immiscible blends composed of crystalline matrix of polyamide-12 (PA) and glassy polystyrene (PS) dispersed phase has been investigated. Other conditions being equal, the effect becomes the more pronounced the lager the draw ratio and the finer the PS dispersion. Since the latter factor is itself a strong function of phase viscosity ratio (μ), the following two techniques of adjusting the optimal value of μ ≈ 1 have been adopted. According to the first one, a selective plasticizer, which is a good solvent for the PS minor phase and a nonsolvent for the PA matrix phase, was added to the more viscous PS. According to the second approach, the value of μ was varied by the use of PS samples of different molecular weights. It was shown that significant reinforcement effect appears on drawing regardless of the method of adjusting optimal phase viscosity ratio. These data as well as the results obtained with the help of IR-dichroism and transmission electron microscopy techniques evidence that the formation of a much more ordered crystalline morphology of the PA matrix located at the PS/PA interfaces and a large interface area are mainly responsible for the discussed reinforcement phenomenon. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1299–1305, 2007

Possible approaches to synthesis of 5-methyl-4-oxo-2-(coumarin-3-yl)-N-aryl-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxamides 4 have been discussed. It is shown that the preferable approach is cyclization of 2-iminocoumarin-3-carboxamides 1, utilizing 5-amino-3-methyl-N2-arylthiophene-2,4-dicarboxamides 2 as binucleophilic reagents. The proposed procedure allowed us to easily obtain 4 in two stages, using common reagents. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:341–346, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20303

In this work the first samples of polymeric semi-conductors of a new structure are produced. Their electric conductivity is of the order ∼10 -2 Ohm -1 . cm -1 and it increases with temperature. Their synthesis includes a stage of radiation grafting of a matrix-type on stretched polyamide films. Conducting molecular circuits in such materials include fragments with conjugated bonds and metal clusters. The alternation of these fragments is determined by the polyamide matrix.

This review is focused on our and literature data on reactions of acyl iodides RC(O)I with organic (alcohols, ethers, esters, carboxylic acids, amino acids, tertiary amines, nitrogen heterocycles, carbamides, thiocarbamides, and thiols) and organoelement compounds (alkoxy silanes, siloxanes, silylamines, silazanes, silicon-containing amines, and ethynyl silanes, germanes, and stannanes). Photolysis of acyl iodides in arene medium yields a-diketones, products of photochemical Friedel-Crafts acylation and iodination of arenes, and polyarylenation.

Intermediates (III) are isolable solids which are used without purification for the following thermal rearrangement.

The reaction of carboxylic acids with SiCl4 can be recommended as a preparative route to corresponding acid chlorides only for weak acids (pKa < 4.7).

In the course of our research on the synthesis of coumarins, the interaction of 2-iminocoumarin-3-carboxamides with a series of 2-aminothiophene-3-carboxamides was studied. It was established that the initial products - 2-substituted coumarin-3-carboxamides - can undergo rearrangement to 2-(coumarin-3-yl)thieno[2,3-d]pyrimidin-4-ones by refluxing in DMF.

Pecularities of deformation of two-phase blends is considered depending on drawing conditions and mechanical properties of each phase. Significant anisotropy of mechanical properties of polymer blends film can take place because of particle orientation of dispersed polymer. This significant anisotropy exists also when there is no orientation of macromolecules in each phase. Possibility is demonstrated to regulate properties of each phase in polymer blends by addition of selective plasticizer which can act only on one polymer phase in two-phase polymer mixture.

The augmented plane wave method (APW) is used for a theoretical study of the electron properties of europium monochalcogenides. Spin-polarized energy band calculations of the ferromagnetic EuO, EuS, and EuSe explain qualitatively the exchange interactions therein. Based on the APW data in the frame of perturbation theory the Coulomb electron—electron interaction at the 4f shell of europium is taken into account for EuO and EuS. The band structures and the multiplet terms of the f6d and 3d94f8 excited states gives a new interpretation of a known experimental spectra for these compounds. [Russian Text Ignored].

The self-consistent relativistic linearized-augmented-plane-wave method is applied to local-density calculation of electronic structure of TmS. It is found, that thulium monosulphide is a metal with a trivalent state of thulium. The influence of spin—orbital interaction is shown for different symmetry states of electrons. Calculated densities of states are used for the estimation of the electron—phonon coupling constant. And in conclusion it is shown that TmS is a high temperature Kondo-like system. [Russian Text Ignored]

The effect of quasi-hydrostatic pressures up to 100 kbar is investigated on the phase transitions of Fe1−xRhx alloys by resistivity measurements. The pressure dependence of the first order antiferromagnetic (AF) to ferromagnetic (FM) phase transformation temperature dTk/dp = 4.4 to 5 K/kbar. The pressure dependence of the second order FM to paramagnetic (PM) transition, i.e. that of the Curie-point is dTC/dp = −0.7 K/kbar. At about 60 kbar the thermal hysteresis diminishes, and above the range of the co-existence of three phases (AF—FM—PM) the pressure dependence of the AF—PM transition is characterized by dT/dp = 0.6 to 1.0 K/kbar. The AF—PM transition is investigated in an Ir-substituted alloy (Fe44Rh49.5Ir6.5) also, where dT/dp = 0.6 K/kbar. [Russian Text Ignored].

The augmented plane wave (APW) method is used for theoretical study of the electronic structure of europium monoxide under hydorstatic pressure. A magnetic state of europium ion at the atmospheric pressure is analysed by comparison of theoretical magnetic form-factor with the experimental one of Cable et al. The energy gap between the filled majority spin f-states and the bottom of the conduction band is found to be closed at the pressure 140 kbar in good agreement with recent experiments of Zimmer et al. [Russian Text Ignored].