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Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. We developed a procedure for determining manganese(II) in wines by stripping voltammetry on a graphite electrode as a poorly soluble compound. The detection limit of manganese(II) is 50 µg/L. The dependence of the analytical signal of manganese(II) on its concentration in solution is linear in the range 0.1–3 mg/L. It is demonstrated that the results of the stripping voltammetric determination of manganese(II) in wines agree with the data obtained by inductively coupled plasma mass spectrometry and EPR spectrom etry.

The dynamic Born charges and the frequency spectra of lattice oscillations in the crystals of ordered and disordered PbSc1/2Ta1/2O3 (PST) and PbSc1/2Nb1/2O3 (PSN) solid solutions have been calculated within the framework of the generalized Gordon-Kim model with allowance for the dipole and quadrupole polarizabilities. The phonon spectra of both compounds contain ferroelectric soft modes. The influence of various interactions on the magnitude of dynamic charges and ferroelectric instability in PSN and PST solid solutions has been studied and it is shown that both these charges and the ferroelectric instability are determined by the competition between long-range dipole-dipole interactions and short-range dipole-charge interactions, the determining role played by the interaction of Nb (Ta) cations and oxygen anions in the Nb-O (Ta-O) bond direction.

The properties of a superconductor featuring strong electron-phonon and electron-impurity interactions have been studied in a single-band approximation. It is shown that the elastic scattering of electrons on static impurities decreases the electron-phonon interaction constant in proportion to the ratio of the electron-impurity relaxation rate and the seeding band width. The optical spectral weight (integral of the real part of the optical conductivity) in various energy intervals of a metal in the normal and superconducting states has been calculated as a function of the temperature and the superconducting gap. In the region of large (compared to the phonon) energies, the dependence of the spectral weight on the superconducting gap is weak, while the dependence on the temperature is completely determined by the corresponding dependence of the relaxation rate due to the elastic electron-phonon scattering far from the Fermi surface. It is shown that a difference in behavior of the spectral weight between the normal and superconducting states at lower energies is determined by so-called Holstein’s shift of the feature in the optical conductivity spectrum (rather than by the gap width, as it is commonly believed) and sharply decreases upon the introduction of impurities.

We report ab initio linear-response calculations of the phonon spectra and the electron-phonon interaction for several transition metal carbides and nitrides in a NaCl-type structure. For NbC, the kinetic, optical, and superconducting properties are calculated in detail at various pressures and the normal-pressure results are found to agree well with the experiment. Factors accounting for the relatively low critical temperatures T c in transition metal compounds with light elements are considered and the possible ways of increasing T c are discussed.

A brief review is given on the studies of ferroelectricity in perovskites. Early phenomenological theories of displacement-type ferroelectrics are considered. Two markedly different approaches based on density-functional theory are described. In one approach, the electron density of crystal is determined as a sum of Bloch functions. In the other, it is constructed as a superposition of the electron densities of individual ions. The latter approach gives a microscopic justification for the old phenomenological theories. We show that some phenomena in perovskites, which seemingly are of the order–disorder origin, can be explained by quasi-one-dimensional peculiarities of lattice dynamics.

A detailed investigation of multiband superconductivity and Leggett’s mode in the Mg1−x AlxB2 (0 ≤ x ≤ 0.45) system was carried out using tunneling and Andreev spectroscopy. Temperature dependences of superconducting gaps Δσ and Δπ and their variation upon the degree of disorder and the Al concentration were studied. The dependence of the Leggett’s mode energy e0 upon the values of the gaps Δσ and Δπ has been derived.

The article covers organizational aspects of development of innovative technologies in the field of regenerative medicine. It is shown that for the effective design and implementation into medical practice of regenerative medicine requires a united complex of military health care, military medical research and education. The main goal is to formate a biological insurance of personnel to treat different consequences of radiological incidents, burn disease, identification of the remains of the victims; the maximum returning to action after disturbed as a result of health services. Proposes the creation of "Interdepartmental Clinical Research and Education Center for Regenerative Medicine", combining research, clinical, industrial and educational potential of the leading institutions of various departments that will enhance the national security of the Russian Federation.

Selective study of the electron transport chain components in living mitochondria is essential for fundamental biophysical research and for the development of new medical diagnostic methods. However, many important details of inter- and intramembrane mitochondrial processes have remained in shadow due to the lack of non-invasive techniques. Here we suggest a novel label-free approach based on the surface-enhanced Raman spectroscopy (SERS) to monitor the redox state and conformation of cytochrome c in the electron transport chain in living mitochondria. We demonstrate that SERS spectra of living mitochondria placed on hierarchically structured silver-ring substrates provide exclusive information about cytochrome c behavior under modulation of inner mitochondrial membrane potential, proton gradient and the activity of ATP-synthetase. Mathematical simulation explains the observed enhancement of Raman scattering due to high concentration of electric near-field and large contact area between mitochondria and nanostructured surfaces.

Tyrosine fluorescence in native proteins is known to be effectively quenched, whereas its emission increases upon proteins’ unfolding. This suggests that tyrosine fluorescence could be exploited for probing structural rearrangements of proteins in addition to the extensively used tryptophan emission. We studied the possibility of using tyrosine fluorescence as an indicator of surfactant-induced conformational changes in albumins. It was shown that fluorescence of tyrosine residues, which are uniformly distributed all over the protein molecules, allows the detection of subtle structural rearrangements of proteins upon surfactant binding, which do not influence the properties of a single tryptophan residue buried in the inner hydrophobic region of human serum albumin. Tyrosine fluorescence properties, including its fluorescence lifetime, revealed the multistage character of surfactant binding to albumin, consistent with the data provided by other methods. The obtained results demonstrate the possibility of probing conformational changes in proteins using tyrosine photophysical parameters as indicators.

The thermopower of cesium has been measured in the region of existence of four phases (I, II, III, and IV) at high pressures up to 7 GPa. The initial phase of cesium and three phases formed under pressure with various crystal structures have a positive thermopower. The thermopower of all three high-pressure phases decreases in magnitude as the pressure increases.

Неходжкинские лимфомы (НХЛ) - гетерогенная группа лимфопролиферативных заболеваний, различающихся по морфологическому строению, клинической картине, характеру и результатам лечения. В большинстве случаев НХЛ дебютируют поражением лимфатических узлов (нодальные лимфомы), однако в последние годы значительно увеличилось число больных экстранодальными лимфомами, среди которых важное место занимают НХЛ мочеполовой системы. Для дифференциальной диагностики с другими новообразованиями и стадирования НХЛ мочеполовой системы необходимо проведение обследования, включающего биопсию опухоли с гистологическим и иммуногистохимическим исследованием. Кроме того, требуются цитогенетические и молекулярно-генетические исследования, УЗИ внутренних органов, КТ груди и всех этажей брюшной полости, стернальная пункция и трепанобиопсия костного мозга. Это позволяет определить вариант и распространенность НХЛ и выбрать соответствующую тактику терапии, а в ряде случаев, учитывая высокую чувствительность НХЛ к химиолучевой терапии, избежать обширных хирургических вмешательств.

Experimental and theoretical high-pressure research on simple metals is reviewed. It is shown that simple metals undergo transition sequences from close-packed highly-symmetric to less-symmetric and often less closely packed structures as pressure is varied over a wide range. A number of theoretical perspectives concerning the nature of this behavior are reviewed with a focus on the electrophysical properties of lithium and calcium at high pressure. Static and shock-wave compression data on Li and Ca are presented.

We obtain a one-parameter family of (q, p)-representations of quantum mechanics; the Wigner distribution function and the distribution function we previously derived are particular cases in this family. We find the solutions o the evolution equations or the microscopic classical and quantum distribution functions in the form of integrals over paths in a phase space. We show that when varying canonical variables in the Green’s function of the quantum Liouville equation, we must use the total increment o the action functional in its path-integral representation, whereas in the Green’s function of the classical Liouville equation, the linear part o the increment is sufficient. A correspondence between the classical and quantum schemes holds only under a certain choice of the value of the distribution family parameter. This value corresponds to the distribution unction previously found.

First-principles calculations of the physical properties of ionic crystals are reviewed. Two markedly different approaches within the framework of the density functional theory are described. In one of them, the electron spectrum and wave functions are treated within the standard band picture based on the solution of Kohn–Sham equations. In the second approach, the total electron density of a crystal is represented as a superposition of the densities of individual ions. The problem of determining the electric polarization of a crystal is discussed for each approach. It is shown that it is the use of Bloch functions rather than the physics of the phenomenon that complicates the solution of this problem within the Kohn–Sham framework. The deformable and polarizable ion model is described in detail, and its application to calculating many properties of ionic crystals, including the lattice dynamics and structural stability of crystal phases, is discussed.

Ab initio calculations of the superconducting properties have been performed for niobium carbide (NbC) at normal pressure and upon a 15 and 30% compression. Factors accounting for the relatively low values of the transition temperature T c in transition metal carbides are considered and the possible ways of increasing this parameter are discussed.

The forms of iron in the composition of cenospheres prepared from energy ashes are investigated using the electron paramagnetic resonance (EPR) method, Mossbauer spectroscopy, and thermodynamic analysis. Cenospheres of controlled composition are produced by sieve, gravimetric, and magnetic separation. It is established that iron in two states (Fe3+, Fe2+) enters into the cenosphere composition. At an Fe2O3 content of 3–4 wt %, iron(III) predominantly occurs in two forms: single ions in the glass and particles of the superparamagnetic phase with a spinel structure. These particles are 30–50 A in size and are dispersed in aluminosilicate glass. The sublattices of the superparamagnetic spinel are diamagnetically diluted with Mg2+ and Al3+ ions. At an Fe2O3 content of higher than 7 wt %, cenospheres also contain a magnetic phase based on defect magnetite.

Electrical resistivity of two crystal phases of shock-compressed calcium and its melt was measured in a range of high pressures (10–50 GPa) and temperatures (800–1600 K). The thermodynamic equilibrium curves were constructed for different calcium phases and the shape of Hugoniot adiabat was determined in the region where it intersects the equilibrium curves. It is shown that sharp kinks observed earlier in the Hugoniot adiabat in shock experiments were caused not by the jumplike electronic transitions but by the intersections of the adiabat and the phase-equilibrium and melting curves. The electronic spectra of the calcium crystal phases were calculated using the electron-density functional method; the computational results are used to explain the observed behavior of the Ca resistivity under compression.

The correlation between the density ρs(T→0) of superconducting condensate and the superconducting transition temperature Tc in underdoped HTSC systems is considered. It is shown that the linear relation between ρs(0) and Tc observed in some experiments can easily be interpreted in the framework of the conventional Bardeen-Cooper-Schrieffer (BCS) model without invoking any exotic superconductivity models.

The break-junction tunneling has been systematically investigated in MgB2. Two types of the break-junction contacts have been exploited on the same samples, which demonstrated tunnel contact like (SIS) and point contact like (SnS) behavior. Both of them have shown the existence of the two distinct energy gaps. We have also observed peculiarities on the I(V)- characteristics related to Leggett's collective mode assisted tunneling.

Background: The claustrum is a brain structure found in both hemispheres beneath the inner surface of the neocortex in the region of the insula and is bordered by the external and extreme capsule. ...

Orange carotenoid protein (OCP) is the photoactive protein that is responsible for high light tolerance in cyanobacteria. We studied the kinetics of the OCP photocycle by monitoring changes in its absorption spectrum, intrinsic fluorescence, and fluorescence of the Nile red dye bound to OCP. It was demonstrated that all of these three methods provide the same kinetic parameters of the photocycle, namely, the kinetics of OCP relaxation in darkness was biexponential with a ratio of two components equal to 2:1 independently of temperature. Whereas the changes of the absorption spectrum of OCP characterize the geometry and environment of its chromophore, the intrinsic fluorescence of OCP reveals changes in its tertiary structure, and the fluorescence properties of Nile red indicate the exposure of hydrophobic surface areas of OCP to the solvent following the photocycle. The results of molecular-dynamics studies indicated the presence of two metastable conformations of 3′-hydroxyechinenone, which is consistent with characteristic changes in the Raman spectra. We conclude that rotation of the β-ionylidene ring in the C-terminal domain of OCP could be one of the first conformational rearrangements that occur during photoactivation. The obtained results suggest that the photoactivated form of OCP represents a molten globule-like state that is characterized by increased mobility of tertiary structure elements and solvent accessibility.

Tunneling spectroscopic studies of high-temperature superconductors (HTSC) are overviewed. It is demonstrated, in particular, that the superconducting gaps determined from Andreev reflections and tunneling current-voltage characteristics coincide at all doping levels. Facts are presented evidencing the strong electron-phonon interaction in the HTSC systems. The nature of the so-called pseudogap, which is observed in some tunneling experiments, is briefly discussed.

We formulate and solve the problem of finding a distribution function F(r,p,t) such that calculating statistical averages leads to the same local values of the number of particles, the momentum, and the energy as those in quantum mechanics. The method is based on the quantum mechanical definition of the probability density not limited by the number of particles in the system. The obtained distribution function coincides with the Wigner function only for spatially homogeneous systems. We obtain the chain of Bogoliubov equations, the Liouville equation for quantum distribution functions with an arbitrary number of particles in the system, the quantum kinetic equation with a self-consistent electromagnetic field, and the general expression for the dielectric permittivity tensor of the electron component of the plasma. In addition to the known physical effects that determine the dispersion of longitudinal and transverse waves in plasma, the latter tensor contains a contribution from the exchange Coulomb correlations significant for dense systems.

We introduce some versions of the notion of the combinatorial p-parameter property for polyhedra whose general meaning reduces to search for the number of parameters ensuring unique determination of a polyhedron locally on assuming given edge lengths and combinatorial structure.

We studied the possible use of the detergent Brij 58 in physiological experiments for the reorientation of right-side-out plasmalemmal vesicles, which were isolated from wheat (Triticum aestivum L.) coleoptiles. The activities of K+, Mg2+-ATPase and the ATP-dependent H+-potential were higher in Brij 58-treated vesicles, whereas membrane permeability for K+ and Na+ remained unchanged. Brij 58 did not suppress the ATP-dependent IAA transport into vesicles and RNA polymerase II activation by IAA–protein plasmalemmal complexes in the system of isolated nuclei. The conclusion was that, using Brij 58, we could obtain the plasmalemmal fraction, which consisted almost completely of closed inverted vesicles. These vesicles can be applied for the in vitro study of the processes, which occur on the cytosolic plasmalemmal surface.

A high-resolution Shack-Hartmann sensor is developed, which enables one to perform the fast time sampling and measuring both the wavefronts and the intensity distributions of high power lasers over the square entrance pupils up to 15x15 mm. The sensor has a flexible program interface with two built-in algorithms for reconstructing the laser wavefronts. Keywords—Shack-Hartmann sensor, high-power lasers, phase reconstruction, intensity distribution The experimental testing, assembling, and alignment of new high-power femtosecond laser systems based on the coherent superposition of multiple laser beams require to evaluate precisely the quality of both the separate beams in different channels and the resultant output laser beam. The first stage of this evaluation assumes a high-precision, fast, and high-resolution measurement of the transverse distributions of the phase and intensity of the beams. The necessity of this measurement is stipulated, in turn, by the effort of avoiding the emergence of hot spots within the transverse intensity distributions of laser beams and of reaching a higher level of the resultant output beam. Ideally, the central region of the beams must be free from the intensity and phase variations. Using the results of the measurement one can further perform a more accurate alignment of the spatial filters (in the form of vacuum telescopes) of the laser system in different channels and even to perform the compensation of the phase inhomogeneity of solid-state active crystals of the whole laser system by a correction phase plate. The most complicated part of the mentioned evaluation is the measurement of the phase distributions of laser beams. Due to a wide spectrum of a femtosecond laser radiation the use of classic interferometers is not feasible here and presents a real challenge. One of the most convenient tools for this measurement is a Shack-Hartmann sensor [see, e.g., 1] which is capable to operate in white light and to evaluate simultaneously both the phase and intensity maps. In the present work we report on the preliminary results of the numerical simulation of a high-resolution, fast, and wide-aperture Shack-Hartmann sensor together with describing the algorithms of reconstructing the wavefronts built-in a program interface. A developed Shack-Hartmann sensor consists of a highresolution commercially available camera, several replaceable microlens matrices (lenslets) adjusted before a chip of the camera and having different numbers of microlenses, and a program interface. The camera has a global shutter and a large CMOS chip with the overall dimensions of about 15x15 mm. The dimensions of the experimental lenslet matrices we used are equal to 32x32, 64x64, and 102x102. When performing the computer simulation of the process of wavefront measurement with the use of a Shack-Hartmann sensor, we have examined the main theoretical characteristics of the sensor for even higher binary dimensions of its lenslet matrices. Making the time optimization of a modal algorithm for reconstructing the wavefronts we have obtained a fast convergence of the process of approximation of the wavefronts by the Zernike polynomials. The results of the computer simulation of a method of spectral analysis with the use of N Zernike polynomials are presented in Table 1. The simulation is performed with a personal computer on the base of Intel Core 2 Duo CPU (2 GHz) running under Windows XP OS.

The current article is dedicated to promising technologies of packed red blood cells production and storage. The following new technical approaches are presented: (1) erythrocytes storage in strict anaerobic argon-hydrogen environment, (2) lyophilization of erythrocyte suspension by its atomization in nitrogen gas, (3) lyophilization of erythrocytes by directional freezing under the influence of radio frequency radiation, (4) automated pharming of antigen free packed red blood cells from progenitor cell directly at the battlefield.

The effect of the inhibitors of calcium channels on red-light (R)-mediated inhibition of gravitropic bending was studied in excised wheat (Triticum aestivumL.) coleoptiles. The effect of a short R pulse (2 min) preceding the gravitropic stimulation was completely alleviated by a similar pulse of far-red light (FR), when the latter preceded the gravitropic stimulation and the delay between R and FR pulses did not exceed 20 min. Plant memory of the R pulse lasted up to 40 min. Neither R nor FR exerted any effect on the gravitropic reaction when applied after gravitropic stimulation. Treatment with 1 μM of verapamil, LaCl3, GdCl3, or ruthenium red before the gravitropic stimulation prevented or released the R-exerted suppression of the gravitropic response (GR). The GR in coleoptiles is apparently regulated by the phytochrome system at the induction phase and involves calcium channels.

Sensors based on thick-film graphite and screen-printed electrodes open up a new era in stripping voltammetry. The increasing application of the stripping analysis in laboratory, field, and on-line variants is expected in the near future. The use of modified thick-film graphite and screen-printed electrodes allows solving main problems of the method: toxicity of mercury and mechanical regeneration of the solid electrode surface. However, one of the problems with the stripping voltammetric method, namely the interference of organic compounds, cannot be solved without sample pretreatment. New four-electrode sensors based on thick-film graphite and screen-printed carbon electrodes for analysis of natural and waste waters are described. The analysis is performed in three steps: sample pretreatment, accumulation of the analyte on the electrode surface, and measurement. The measuring cells have a small volume (e.g., 0.2–0.8 ml) sufficient for uniform mixing of the test solution and introduction (if required) of standard additions. A solid electrolyte can be placed in the cell. The sensors were used for determination of Cu, Pb, and Cd concentrations. The detection limit is n × 10−7 g l−1. Some results of the analysis of model solutions, river and waste waters with the use of the standard addition method or calibration curves are given. © 2002 Wiley Periodicals, Inc. Field Analyt Chem Technol 5: 260–271, 2001; DOI 10.1002/fact.10006

The changes in the specific binding of 3H-IAA to the plasmalemma from segments of wheat (Triticum aestivumL.) coleoptiles and the physiological activity of the IAA–protein complexes thus formed in dependence on the duration of gravitational stimulation (GS) (1 g) were studied. The overall inhibition of the formation of IAA–protein complexes was accompanied by a transverse polarization of their functional activity occurring as early as within two minutes after the onset of GS. The pretreatment of plasmalemmal vesicles with 0.1 μM CaCl2prevented the in vitroIAA–protein complex formation in the plasmalemma. It is suggested that the GS results in an increase in the plasmalemma permeability for Ca2+, which reduces the capacity of the plasmalemma to bind IAA at the early stages of the gravitropic response.

The 29th Research Institute recently published its latest transformation parameters for WGS and PZ 90. Because these tranformation parameter estimates were derived from stations located within Russia, variance-covariance propagation was carried out to study the benefits of a better global distribution of stations. An example that includes two stations in North America is presented. The transformation improves significantly. © 1999 John Wiley & Sons, Inc.

A description is given of a planned prism beta spectrometer intended for precise measurements of conversion electron spectra both from radiative capture reactions and radioactive sources, and its characteristics are presented.

The concept of regenerative medicine has acquired a considerable progress especially in NATO armies. Regenerative medicine with its innovative technologies becomes a powerful tool in solving ensuring problems of military medical institutions with medicines on the basis of donor blood, tissues and artificial skin. The centers of regenerative medicine and cell therapy developed by many of the leading research institutions in our country and abroad. Foundation of a Biological Register of Russian Armed Forces with a Centre of Cellular and Genetic technologies based at the Military Medical Academy will satisfy needs of military medicine in cellular technologies. Scientific research works in experimental biology and clinical studies of stem cells will enable to generate biological safety of servicemen.

Based on analysis of the catalytic properties and defect structure of oxide catalysts, the new systematization of catalysts for the oxidative coupling of methane (OCM) reaction has been proposed. The oxygen defects (anion vacancies for SrO and Li/Bi2O3 (0.1 at.%)) and impurity defects (transition metal ions for Li/CaO, Na/CaO) was proposed to play the important role for the process of N2O activation in OCM. The addition of 02 in CH4-N2O reaction mixture decreased the rate of N2O decomposition over SrO and Li/Bi2O3, while for M/CaO catalysts such effect was not observed. It was explained by the fact that the activation of O2 and N2O in OCM process occurs on the same centres for the first group of catalysts and different centres for the second group of catalysts. Two temperature ranges of proceeding of OCM reaction over SrO was established. The mechanism in which CO2 is a poison for active oxygen species was proposed.

We show that semiconductor nanocrystals (quantum dots, QD) can be used to increase the absorption capacity of pigment-protein complexes. In a mixture of photosystem 2 core complex (PS2) and QD, the fluorescence of the latter decreases several-fold due to the transfer of the absorbed energy to the PS2 core complex. We discuss Förster's inductive-resonance mechanism as a possible way of energy transfer in donor-acceptor pairs QD-PS2 core complex. Calculations based on the experimental data show that the enhancement of PS2 fluorescence and the rate of Q(A) reduction increase up to 60% due to efficient energy migration from QD to PS2.

Prokaryotic cells, including cyanobacteria, respond to a decrease in ambient temperature by activation of numerous cold shock genes. Low temperatures cause a decrease in membrane fluidity, which is maintained at some optimal level mainly by fatty acid (FA) desaturases. Here, temperature-dependent expression of the desB gene for the omega3-desaturase in Synechocystis, which synthesized polyunsaturated FAs, and in its mutant, desA-/desD-, which is defective in genes for delta12- and delta6-desaturases and is capable of synthesizing only monounsaturated FAs was studied. Low temperatures caused the increase in the amount of the desB mRNA in the wild-type cells with the maximum observed at 24 degrees C. In the double mutant desA-/desD- cells, the maximum amount of this mRNA was accumulated at 28-30 degrees C. Thus, our studies of the desB gene for the omega3-desaturase demonstrated that temperature-dependent expression of genes, which are responsible for the maintenance of the optimal membrane fluidity, depends on physical state of these membranes and is regulated by a feedback mode.

The catalytic properties of Na/CaO with a low amount of alkali promoter and SrO were studied under comparable conditions, using CH4-O2 and CH4-N2O reaction mixtures. CH4 conversion was similar for both oxidants (

Due to exposure to emissions from a protein-vitamin concentrate-manufacturing enterprise, the total and allergic morbidity rates remained high in the Blagoveshchensk population during a follow-up, the incidence of asthma and atopic dermatitis being on the rise and that of pollen disease on the decrease. The findings show the need for a further follow-up of the health status of the population of this area, the living conditions in which are risk factors for allergic and toxic allergic diseases even after microbiological industry closure.

The optical conductivity and permittivity spectra of Ba(Fe${}_{0.9}$Co${}_{0.1}$)${}_{2}$As${}_{2}$ films (${T}_{c}=20 \text{K}$) are analyzed together with the literature data on photoemission and specific heat. In the superconducting state at all temperatures up to ${T}_{c}$ the temperature dependence of the magnetic field penetration depth is well described within the generalized two-band BCS model with intraband and interband pairing interactions considered. It is shown that the small superconducting energy gap $2{\ensuremath{\Delta}}^{(1)}=3.7\text{meV}$ develops in the electron subsystem while the larger gap $2{\ensuremath{\Delta}}^{(2)}=7.9\text{meV}$ opens in the hole subsystem. The normal state parameters, such as plasma frequency and scattering rate, of electron and hole conduction bands are determined.

The low-energy electrodynamic response of a series of ${\text{La}}_{0.25}{\text{Ca}}_{0.75}{\text{MnO}}_{3}$ samples of different morphology is systematically studied in the frequency range from 4 to $700\text{ }{\text{cm}}^{\ensuremath{-}1}$ (0.1--20 THz, quantum energies 0.4--90 meV) with particular attention focused at frequencies below $40\text{ }{\text{cm}}^{\ensuremath{-}1}$. In the antiferromagnetically ordered phase below 140 K, a resonancelike absorption band appears in the spectra around $20--40\text{ }{\text{cm}}^{\ensuremath{-}1}$ that is assigned to acoustical phonons which acquire optical activity due to a fourfold superstructure appearance in the crystallographic $a$ direction and correspondent Brillouin-zone folding. Nanosize effects in charge and magnetic subsystems are investigated by measuring the spectra of samples with grain diameters reduced from several micrometers down to 40 nm. A strong relaxation in the lowest-frequency spectra is observed above 100 K in all samples, indicating that the charge-order transition shows characteristics typical for order-disorder transitions.

In Part I we discuss accumulating experimental evidence related to the structure and origin of the bosonic spectral function in high-temperature superconducting (HTSC) cuprates at and near optimal doping. Some global properties of the spectral function, such as number and positions of peaks, are extracted by combining optics, neutron scattering, ARPES and tunnelling measurements. These methods give convincing evidence for strong electron-phonon interaction (EPI) with the coupling constant between 1-3 in cuprates near optimal doping. Here we clarify how these results are in favor of the Eliashberg-like theory for HTSC cuprates near optimal doping. In Part II we discuss some theoretical ingredients - such as strong EPI, strong correlations - which are necessary to explain the experimental results related to the mechanism of d-wave pairing in optimally doped cuprates. These comprise the Migdal-Eliashberg theory for EPI in strongly correlated systems which give rise to the forward scattering peak. The latter is further supported by the weakly screened Madelung interaction in the ionic-metallic structure of layered cuprates. In this approach EPI is responsible for the strength of pairing while the residual Coulomb interaction (by including spin fluctuations) triggers the d-wave pairing., 59 pages, 38 figures, review article

Time‐ and wavelength‐correlated single photon counting and fs‐absorption change measurements of the excitation dynamics were performed on phycobiliproteins (PBP) and whole cells of A.marina. The excited state population was simulated with a set of coupled linear differential equations. The overall energy transfer from PBP to the membrane intrinsic Chl d antenna was found to be limited by electronic excitation energy transfer (EET) along all coupled pigments in the PBP from the short wavelength phycocyanin (PC) molecules to the “terminal emitter” (TE) allophycocyanin (APC). Our results reveal that the EET step from TE in the PBP antenna to the first Chl d acceptor occurs with a time constant of 20–30 ps leading to a 70–80 ps time constant observed in the fluorescence decay which describes the overall (diffusive) EET from PBP to Chl d [1]. The overall EET is therefore limited by the diffusive EET along the PBP antenna. Based on a Forster type EET the distance between the TE in the PBP antenna and the first neighbour Chl d molecule is determined to be 2.7 nm for a 20 ps transfer step.

The Gordon-Kim electron gas model is generalized to include a dipole polarization of the ions. The expression for the total energy of ionic crystals is derived including its polarization part. The frequencies of LO and TO phonons at the \ensuremath{\Gamma} point are calculated. Good agreement with experimental data for a number of alkali halides is obtained.

Oxidative coupling of methane has been studied over two Li/CaO systems with low ( 2 and N 2 O as oxidants. It was shown that replacement of O 2 by N 2 O in the reaction mixture results in the more selective oxidation of CH 4 to C 2 hydrocarbons, decreases CO formation and alters the methane conversion scheme. The signals from V- centers (O- near cation vacancy), Fe 3+ and Li + O − are observed in the EPR spectrum of γ-irradiated Li/CaO after contact with CH 4 - N 2 O at 1023 K. In the presence of CH 4 − O 2 , the defects observed after irradiation are [LiCO 3 ], CO 2 and O 3 − centers associated with cation vacancy sites. The possibility of defect participation at the stages of the electron transfer and / or in the formation of active oxygen species is discussed.

The relationship of the catalytic activity of Li/CaO (0 ⩽ Li ⩽ 1.7 at%) in CH4 oxidative coupling with the defectness of the matrix has been studied. It was shown that the activity of undoped CaO increases with the rise of concentration of anion and cation vacancies. The concentration and nature of defects in the pure CaO are independent of the composition of the gas (O2, N2O, CH4 or reaction mixture). The incorporation of Li ions into the CaO lattice and also the treatment of Li/CaO with the reaction mixture lead to a change of the character of bulk defects and catalytic properties of the oxide. The signals from O3−, CO2− and LiCO3− centers are detected in the EPR spectra of γ-irradiated Li/CaO catalysts after the contact with the CH4-O2 mixture. Such defects are not observed when a CH4-N2O mixture is used. Simultaneously, the replacement of O2 by N2O in the reaction mixture is accompanied by the decrease of the CO formation rate and the increase of activity in the C2-product formation.