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The 14th Electromagnetic and Light Scattering Conference (ELS-XIV) was held at the Universit de Lille 1, Villeneuve d'Ascq, France on 17-21 June 2013. The conference was attended by 200 scientists from 26 countries. The scientific program included one plenary lecture, 12 invited reviews, 100 contributed oral talks, and 86 poster presentations. The program, the abstracts, and the slides of the oral presentations are available at the conference web site http:www-loa.univ-lille1.frELS-XIV. To highlight one of the traditional ELS themes, the ELS-XIV featured a special session on Remote sensing of aerosols and clouds using polarimetric observations. This session was sponsored and co-organized by the French space agency CNES and attracted representatives from nearly all research teams word-wide involved in the development and active use of space-borne, in situ, and ground-based polarimetric observations.

Mossbauer spectroscopy was used for direct experimental measurement of the Neel barrier height for magnetization reversal in ensembles of interacting γ-Fe2O3 nanoparticles. As the barrier height is proportional to the size of the magnetic cluster, these measurements enable an evaluation of the relative sizes of the magnetically coupled clusters that are formed during the manufacture of the magnetic hyperthermia beads. For the hyperthermia beads, which were synthesized and studied in the work, an increase in the size of the magnetically coupled cluster corresponds to a reduction of the specific loss power.

Water soluble magnetite iron oxide nanoparticles with oleic polymer coating and average diameters in the range of 5–25 nm, previously determined by TEM, were characterized using Mossbauer, magnetization and X-ray diffraction measurements. Comparative analysis of the results demonstrated a large diversity of magnetic relaxation regimes. Analysis showed the presence of an additional impurity component in the 25 nm nanoparticles, with principally different magnetic nature at the magnetite core. In some cases, X-ray diffraction measurements were unable to estimate the size of the magnetic core and Mossbauer data were necessary for the correct interpretation of the experimental results.

Principal difference of magnetic nanoparticles from the bulk matter which cannot be ignored when constructing upon them combined metamaterials and modern devices is the essential influence on their behavior thermal fluctuations of the environment. These disturbances lead to specific distributions of the particles characteristics and to stochastic reorientations of their magnetic moments. On the basis of quantum-mechanical representation of the particle possessing intrinsic magnetic anisotropy and being placed onto the external magnetic field we developed general approach to describe equilibrium magnetization curves and relaxation Mossbauer spectra of magnetic nanoparticles for diagnostics of magnetic nanomaterials in the whole temperature or external field ranges. This approach has universal character and may be applied not only to the systems under thermal equilibrium, but may in principle describe macroscopic dynamical phenomena such as magnetization reversal.

119Sn Mossbauer spectroscopy was used to study the fluctuations of antiferromagnetic domains in the heavy-fermion CePdSn Kondo compound. The temperature evolution of the experimental spectra was described within both two- and multi-level relaxation models. The difference between these two approaches is discussed. The temperature dependence of the relaxation rate of the domain’s magnetization and the density of itinerant electrons near the tin atoms are investigated.

Mossbauer spectroscopy in a weak static magnetic field and measurements of isothermal magnetization loops were used to study the effect of polymer coating of the γ-Fe 2O3 nanoparticles on the magnetic properties of concentrated ensembles of such nanoparticles. It was found that the individual coating of the nanoparticles by a ∼ 1 nm layer of the polymer leads to the observable changes in the shapes of the Mossbauer spectra and the magnetization curves of the ensembles. Modeling of the experimental magnetization curves in the classical Langevin model and analysis of the Mossbauer spectra in the generalized multi-level relaxation model revealed that the establishment of interparticle magnetic dipole interactions leads to both a ∼ 30 % increase in the magnetic anisotropy constant and a ∼ 35 % increase in the width of the hysteresis loop.

Biodegradation of a 57Fe3O4 - based dextran - stabilized ferrofluid in the ventricular cavities of the rat brain was studied by X-ray diffraction and Mossbauer spectroscopy. A two-step process of biodegradation, consisting of fast disintegration of the initial composite magnetic beads into separate superparamagnetic nanoparticles and subsequent slow dissolution of the nanoparticles has been found. Joint fitting of the couples of Mossbauer spectra measured at different temperatures in the formalism of multi-level relaxation model with one set of fitting parameters, allowed us to measure concentration of exogenous iron in the rat brain as a function of time after the injection of nanoparticles.

Fe3O4 based ferrofluid was injected transcranially in the ventricle of the rat brain. At 3 months after the injection the rat was sacrificed and the brain was investigated by Mossbauer spectroscopy and histological Perls Prussian blue method. Joint analysis of histological and Mossbauer data confirms that superparamagnetic nanoparticles Fe3O4, which constituted about 91 % of the iron of the ferrofluid, were cleared from the brain, while the concomitant chemical compound containing ferric ion in the high-spin state, remains intact.

In order to extract a quantitative information about characteristics of the magnetic nanoparticles injected into a living organism it is necessary to define a model of the magnetic dynamics for fitting self-consistently the whole set of the experimental data, specifically, the evolution of Mossbauer spectral shape with temperature and external magnetic field as well as the magnetization curves. We have developed such a model and performed such an analysis of the temperature- and magnetic field-dependent spectra and magnetization curves of nanoparticles injected into mice. This allowed us to reliably evaluate changes in the characteristics of the residual particles and their chemical transformation to paramagnetic ferritin-like forms in different mouse organs as a function of time. Actually, the approach makes it possible to quantitatively characterize biodegradation and biotransformation of magnetic nanoparticles delivered in a body.

The paper shows the necessity of a differentiated approach to the planning of the rural territories development. The article focuses on the criteria of grouping rural territories. The affinity to city (center) is a key criterion that determines rural social and economic development in many respects. The author offers his approach to the methods of differentiation of intra-regional rural periphery. The main feature of the approach is that all the cities of the regional system are used as centers of regional development.

The problems of account of factors, which influence on the wear of objects of the track infrastructure with the purpose of the optimum planning of expenses on reproduction measures and the development of expense method of forming of tariff for access to the infrastructure, are under investigation.

For an 8-month period aerosol optical depth (AOD) is compared, derived over global oceans with five different retrieval algorithms applied to four satellite instruments flown on board three satellite platforms. The Advanced Very High Resolution Radiometer (AVHRR) was flown on board NOAA-14, the Ocean Color and Temperature Scanner (OCTS) and the Polarization and Directionality of the Earth’s Reflectances (POLDER) on board the Advanced Earth Observing Satellite(ADEOS), and the Total Ozone Mapping Spectrometer (TOMS) on board the Earth Probe satellites. The aerosol data are presented on the same format and converted to the same wavelength in the comparison and can therefore be a useful tool in validation of global aerosol models, in particular models that can be driven with meteorological data for the November 1996 to June 1997 period studied here. Large uncertainties in the global mean AOD are found. There is at least a factor of 2 difference between the AOD from the retrievals. The largest uncertainties are found in the Southern Hemisphere, and the smallest differences mostly near the continents in the Northern Hemisphere. The largest relative differences are probably caused by differences in cloud screening.

The report describes the results of a study the effect of pH and binding of six physiologically active compounds (isoproterenol, yohimbine, theophylline, propranolol, clonidine and carbachol) on the molecular structure of human serum albumin (HSA) using dynamic light scattering. It was found that the albumin globule had the most compact configuration (Stokes diameter 59-62A) at physiological pH 7.4. The changes in pH both increased to 8.0 and decreased to 5.4, resulting in the growth of globule size to 72-81A. At acidic shift of pH an additional peak arose in the correlation spectra. This peak was caused by the light scattering on the structures with the Stokes diameters of 29-37A, which conformed to the sizes of the albumin subdomains. The additional peak was not displayed at basic shift of pH. The interaction with propranolol, clonidine and carbachol, which hinder adenylate cyclase (AdC) signaling system of a cell, initiated structural rearrangements similar to acidic transitions. Isoproterenol, yohimbine and theophylline, which activate AdC, caused the conformational changes of HSA similar to basic transitions.

In order to extract quantitative information about characteristics of the magnetic nanoparticles in a media it is necessary to define a model of the magnetic dynamics for treating self-consistently the whole set of the experimental data, particularly, the evolution of Mossbauer spectral shape with temperature and external magnetic field as well as the magnetization curves. We have developed such a model and performed such an analysis of the temperature- and magnetic field-dependent spectra and magnetization curves by the example of nanoparticles injected into laboratory mice. This allowed us to reliably evaluate changes in the characteristics of the residual particles and their chemical transformation to paramagnetic ferritin-like forms in animals organs as a function of time. Actually, the approach makes it possible to quantitatively characterize biotransformation and biodegradation of magnetic nanoparticles delivered in a living organism.

The optimization of kinetic scheme of chemical process is the important stage of computer simulation of chemical processes. This iterative method consists from the next steps: proposition of scheme from theory, translation scheme to the system of ordinary differential equation (ODE), finding solution of this system, comparison results with experimental data, modification of kinetics scheme. ChemPAK software package was created for automation of this process. ChemPAK consists of network database, computational modules and visual interface. User can create and edit systems of chemical equations with unlimited number of equations with easy‐to‐use interface, translate systems of chemical equations to systems of ODE, add some new equations to the translated system and solve this system by using one of ChemPAK computational modules. Optimized kinetics scheme can be used in FLUENT software for modelling fluid flows, heat transfer and chemical reactions. ChemPAK creates FLUENT database file with chemical reaction...

The effect of pH and binding of ten physiologically active compounds (isoproterenol, yohimbine, propranolol, clonidine, phenylephrine, carbachol, tripeptide fMLP, diphenhydramine, chlorpromazine and atropine) on the molecular structure of human serum albumin (HSA) has been studied using the dynamic light scattering. It was found that albumin globule has the most compact configuration (Stokes diameter 59-62 A) at physiological pH 7.4. The changes in pH, both increase to 8.0 and decrease to 5.4, result in the growth of globule size to 72-81 A. At acidic shift of pH an additional peak arises in the correlation spectra caused by the light scattering on the structures with the Stokes diameters of 29-37 A. Those conform to the sizes of the albumin subdomains. The indicated peak is not displayed at basic shift of pH. The interaction with propranolol, clonidine, phenylephrine, carbachol and tripeptide fMLP which hinder adenylate cyclase (AdC) and activate Ca-polyphosphoinositide (Ca-PPI) signaling system of a cell initiates structural rearrangements similar to acidic transitions. Isoproterenol, yohimbine diphenhydramine, chlorpromazine and atropine, which activate AdC and hinder Ca-PPI, cause conformational changes of HSA similar to basic transitions.

Mossbauer spectroscopy is a powerful method for investigation structural, magnetic and thermodynamic properties of magnetic nanoparticles, in particular those delivered in a body. Multiform temperature- and field-dependent Mossbauer absorption spectra of fine particles provides the researcher with rich information about physical characteristics inherent to such particles staying in different environment. With that the 57Fe gamma-resonant spectroscopy is efficiently used to study spin states, electronic and dynamical properties of iron-containing proteins in a living organism. For quantitative estimates of characteristics of the magnetic nanoparticles it is required to define a model of the magnetic dynamics. We have developed such a model and performed consistent least-square fitting procedure for the set of temperature- and magnetic field-dependent spectra as well as magnetization curves of nanoparticles injected into mice. This allowed us to reliably evaluate changes in the nanoparticles characteristics and the chemical transformation of the iron to paramagnetic ferritin-like forms in mouse's organs as a function of time after injection of nanoparticles. In fact, the approach allows the researcher to quantitatively characterize biotransformation and metabolism of magnetic nanoparticles injected into a body.