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The influence of the properties of an aqueous medium on aggregation of dimegin, photoditazine, and radachlorin is comparatively studied. It is noted that the molar extinction nonlinearly depends on the concentration of photosensitizer in solution and the degree of nonlinearity is different for the pharmaceutical form of solutions and solutions prepared with the use of freeze-dried photosensitizer powders. It is shown that the use of surfactants (Pluronic F-127 and polyvinylpyrrolidone) somewhat reduces problems related to aggregation of photosensitizers under study.

The photostability of albumin complexes, Pluronic F-127 complexes and the aqueous solutions of photoditazine and dimegin were investigated. The photodegradation rate of albumin complexes was about four times faster than that of other compositions under study due to the desagregation of photosensitizers.

We compare the photostability of one porphyrin and two chlorine photosensitizers. We show that a higher photostability of dimegine compared to photoditazine and radachlorin is determined both by their different chemical natures and by the fact that the aggregation ability of porphyrin dyes is higher than that of chlorine dyes, which in the solution leads to efficient formation of dimers and higher-order complexes.

The photophysical properties of three photosensitizers—dimegine, photoditazine, and radachlorin—have been comparatively examined. For dimegine and photoditazine, two techniques have been used to measure the singlet oxygen generation quantum yields and the quenching constants of singlet oxygen by dimegine and photoditazine, as well as the dimegine fluorescence quantum yield.

The spectral properties of singlet-oxygen luminescence at the 1Δ g → 3Σ g transition in the presence of rose Bengal as a photosensitizer are analyzed. The effect of iodine in solution in CCl4 on the efficiency of singlet-oxygen generation and on the structure of singlet-oxygen luminescence is shown. The results of studies with tetrachloromethane are compared with the results obtained with other solvents.

The photocatalytic activity of some metal oxides and sulfides, as well of С60 fullerene, is compared using the method of photocatalytic degradation of methylene blue simultaneously with comparison of the efficiency of methylene blue adsorption on solid-phase powders of these oxides, sulfides, and fullerene in aqueous solution of the dye in the absence of irradiation.

Ion production and acceleration is ubiquitous in astrophysical objects but many questions still remain on the mechanisms at play and while laboratory plasmas provide an “accessible” regime, non-thermal ion acceleration has not been observed in the laboratory before the advent of high-power lasers. The authors collide two relativistic plasma flows and observe large energy difference of the protons coming out of the interaction region with or without an external magnetic field, qualitatively corroborating their 1D and 2D particle-in-cell simulations.

The formation processes of a new delta-like object with a hydromorphic landscape in the upper part of the Kapchagai Reservoir on the Ili R.—an internal delta—are considered. The quantitative characteristics of the development of this delta are evaluated using data of Landsat-2, 5, and 7 space images over period 1975–2012. These processes were found to accelerate considerably in the wet year of 2012, and intense under-flooding and salinization of nearby lands were revealed in the Chilikskii alluvial fan on the southern wing of the Kapchagai delta. A consequence of this accumulative process was found to be the development of planar channel deformations of the Ili R. 30 km upstream the Kapchagai delta.

Porphyrin-based substances are modern materials applied in the design of preparations used for photodiagnostics and photodynamic therapy of cancer [1]. The wide interest to their study is drawn by its low toxicity and high selectivity to accumulation in tumor tissues. At that, the photodiagnostics task requires pronounced photoluminescent properties of porphyrins, whereas the photodynamic therapy is based on their high efficiency as regards to photosensibilization of reactive oxygen species, and especially of singlet oxygen.

Four types of carbon nanoparticles: C60 fullerene (crystalline and amorphized) and single- and multilayer carbon nanotubes were studied in the form of solid-phase film coatings for the purpose of obtaining singlet oxygen generation in the process of irradiation of these materials by continuous-wave broadband light-emitting diodes in the visible region spectra and by a monopulse 532-nm neodymium laser.

Singlet oxygen generation is studied in three types of carbon nanoparticles (C60 fullerene and single- and multilayer carbon nanotubes in the form of aqueous suspensions obtained by sonication) upon their irradiation by continuous-wave broadband visible radiation of light-emitting diodes.

It is established that the microdepressions are the most widespread phenomena of zonal soil combinations in the Forest-Steppe zone of Ukraine. They are represented by rather large combinations of zonal soils: different subtypes of gray forest soils and chernozem. It is revealed that fairly common heterogeneities of various forms and depths have become the cause of the variegated field crop rotation of the research farm. Borders of microdepressions indicate a change in the soil properties , the nature of the state of plants and their yields. The main factor of influence is the hydrological regime of microdepressions, which differs significantly from the water regime of the plains. Depending on the redistribution of moisture across the field, varies the physiological state of plants, biological activity of the soil and grain quality indicators changes. The article deals with the distribution of microdepressions in the fields of RF "Velikosnitinske" in the Fastovsky district of the Kiev region and analyzes the seasonal regularities of the influence of these microscales on winter wheat sowing state. The studies were carried out using ground-based field and laboratory methods, as well as aerovisual observations of the quadrocopter. The basis for the study was a preliminary familiarization with the soil maps of the economy and additional field studies, during which numerous microdepressions of various shapes and depths were identified. The area of the agro-research field is 32 hectares. The territory is represented by a large variegated cover in flat areas, is caused by nanorelief and very slightly pronounced depressions with a depth of up to 20-30 cm. Key factor in the formation of heterogeneities here is the specific water regime of the elements of the relief. This is due to the uneven redistribution of atmospheric precipitation over the surface of the territories, which in turn leads to a concentration of moisture in barely noticeable nanoscales and microscales, its filtration deep into the soil profile, washing out the products of soil formation to a noticeable depth. The spatial heterogeneity of the water regime of such territories leads to the same heterogeneity of soil fertility and crop yields. Using ground-based field research and laboratory methods of analysis with the involvement of robotics, namely quadrocopter, it was possible to analyze seasonally patterns of the microscales influence on the state of winter wheat «Merlena» variety. In the course of the research, the yields of wheat within the microdepression border and on the plain, the quality and quantity of gluten were compared, and the soil was analyzed for biological activity. At the end of March 2017 the physiological state of wheat within the microdepression was generally suppressed. The situation changed in summer, when because of relatively dry weather conditions , agroecological state of the vegetation and soil state of the microdepressions was even in better condition than on the plain (control plot). This increased the productivity of wheat within the microdepressions, in comparison with the control plains area. A complex approach to the study of fields productivity problem with available microdepressions of the relief, made it possible to establish a interconnection between the water regime features of experimental field and the agroecological state of vegetation and the individual elements of microdepression soil. It is necessary to continue the research to find new approaches for conducting accurate farming and increasing the productivity of agricultural production.

Considered the phenomenon of spatial heterogeneity of water regime of soils in the Forest-Steppe of Ukraine, its impact on agro-ecological state of soil and regularities of yields formation on the territories with microdepressions. For the research we used the data of Google Earth cartographic service and technical means - a high-precision GPS receiver and Sentinel-2A satellite images. It was found that the uneven distribution of moisture in the agrolandscapes leads to the formation of various soil differences and has a significant effect on the formation of the crop. The results of research can be used in precision farming and in the preparation of detailed soil maps.

Summary Background The problem of transfution-transmitted infections still remains serious and actual for health care despite the detailed testing of donors. Human immunodeficiency virus, hepatitis B and C viruses and human cytomegalovirus are among the most dangerous pathogens that can be transmitted with blood. Previously, a composition consisting of fullerene layer applied on silica gel particles was shown to inactivate influenza virus up to complete loss of infectivity. Methods In the present study the unit has been developed with source of irradiation whose spectrum is appropriate for solid-phase fullerene. The ability of the unit to inactivate the enveloped influenza virus in protein fraction of donor blood has been studied. Results It was shown that at optimized conditions complete inactivation of enveloped virus of extremely high initial titer (7.0–9.5 log10EID50/0.2 mL) in the solution of albumin was achieved after as short time as 30 min of irradiation. This process did not affect the oxidative metabolism of neutrophils and membranes of erythrocytes evaluated by NBT reduction test and morphological analysis of erythrocytes, respectively. Conclusion The data obtained suggests that the method described can be recommended for further development and optimization of the procedure of inactivation of viruses in the preparations of the plasma of donor blood.

General tendencies of changes in the Danube delta landscapes as a result of economic activity were revealed due to comparative analyses of remote sensing data carried out by Landsat satellites. A spatial and temporal differentiation of abrasion, accumulation, waterlogging or flooding processes was investigated on 7 key areas of the delta according to satellite images of Landsat-5 for the years 1986–2011. For the images interpretation the results of the terrestrial route into the Ukrainian part of the delta were used.

The formation of new deltaic landscape at the places where rivers flowing in to the large reservoir is considered as an important and major scientific and economic problem. This process is estimated to be universal having a global character. New landscapes , which are formed by delta type, are vary considerably depending on climatic conditions. So here the processes of deltas formation in the temperate climate of Ukraine and in arid and semiarid climate of Central Asia are discussed in more detail. Schematic observations are made in other regions of the world as well. Problem analysis was carried out using remote sensing data (Landsat satellite imagery) and ground-based observations. Using satellite images made it possible to trace the process in time and space over a long period. Deciphering of satellite images with the help of specialized software gave a possibility to determine the area of the newly formed landscapes and approximately to diagnose soil and vegetation objects that were specified by ground monitoring in the reservoirs.

A new type of proton acceleration stemming from large-scale gradients, low-density targets, irradiated by an intense near-infrared laser is observed. The produced protons are characterized by high-energies (with a broad spectrum), are emitted in a very directional manner, and the process is associated to relaxed laser (no need for high-contrast) and target (no need for ultra-thin or expensive targets) constraints. As such, this process appears quite effective compared to the standard and commonly used Target Normal Sheath Acceleration technique (TNSA), or more exploratory mechanisms like Radiation Pressure Acceleration (RPA). The data are underpinned by 3D numerical simulations which suggest that in these conditions a Low Density Collisionless Shock Acceleration (LDCSA) mechanism is at play, which combines an initial Collisionless Shock Acceleration (CSA) to a boost procured by a TNSA-like sheath field in the downward density ramp of the target, leading to an overall broad spectrum. Experiments performed at a laser intensity of 1020 W/cm2 show that LDCSA can accelerate, from ~1% critical density, mm-scale targets, up to 5 × 109 protons/MeV/sr/J with energies up to 45(±5) MeV in a collimated (~6° half-angle) manner.

The long-term effects of irrigational Bugun’ reservoir in Central Asia on the environmental and ameliorative state of shore landscapes was investigated. Quick Bird Space imagery obtained from Google Maps and retrospective analysis of field and laboratory studies in 60–70 s were used.

The rate and specifics of formation of unique hydromorphic landscapes in the upper parts of three Dnieper reservoirs are assessed based on the analysis of space photographs Landsat-5 and Landsat-7 over a many-year period, as well as topographic and electronic maps. Their area in the examined water bodies was found to exceed 25 thousand ha, and that in the entire chain of reservoirs, to exceed 35 thousand ha. The mean annual rate of increase in the area of hydromorphic landscapes varies from 66 in the Kanevskoe Reservoir to 351 ha/year in the Kievskoe Reservoir; the processes vegetation growth were found to significantly accelerate in the recent years.

Electrostatic wave streamers are excited in an inhomogeneous plasma by a resonant disturbance generated by a mesh antenna biased with an oscillating signal. These low-frequency streamers are observed to move away from the mesh antenna through the under and overdense regions in the plasma. The average velocities of the downward and upward wave streamers are observed to be vd ≈ 2.51 × 105 × cm/s and vu ≈ 1.63 × 105 cm/s, respectively. Based on the order of the velocities of the wave streamers as that of the ion acoustic wave, we name them as ion acoustic wave streamers. Considering the flow of the ions in the plasma due to the density gradient, a theoretical model is developed that explains the nature and propagation characteristics of these experimentally observed streamers.

Desertification of delta landscapes, mainly soil cover, is considered on the example of the Ili River, which basin is located in Kazakhstan and China. Long-term researches on the Ili River were begun in 1968 before creation of the large Kapchagay reservoir and proceed with the use of the space imagery NASA/MODIS/Terra. Degradation of delta landscapes is differentiated in space and in time depending on the features of the natural water regime and its transformation because of flow regulation. The main accent in research has been made on the newest processes of desertification, caused by intensification of irrigation. Characteristics of drying, desertification and salinization of soils in delta are estimated on the state of spring 2008.

This paper presents a review of papers associated with the study of in vitro spectral, fluorescence, and photosensitizing properties, as well as the photostability of low-toxicity photosensitizers based on endogenous porphyrins—the disodium salt of 2,4-di(1-methoxyethyl) deuteroporphyrin IX (dimegin) and the tetrapotassium salt of coproporphyrin III—in comparison with chlorin preparations for medical purposes—Photoditazin, Radachlorin, and Fotolon—when photosensitizer solutions are irradiated in the visible range. The influence of transport additives and proteins on the properties mentioned above is discussed and studied. The results of the study are evidence that it is promising to use drugs based on endogenous porphyrins as effective agents for photodynamic therapy and fluorescence diagnosis, where, along with the photophysical properties of the photosensitizer, a key role is played by photostability, low toxicity, and accumulation selectivity in the pathological foci of the organism, and this is directly associated with the chemical structure of the drug. The results of the latest work carried out at S. I. Vavilov State Optical Institute on this specialization are treated separately.

The relationship between the structural and photosensitizing properties of solid-phase particles of fullerene C60 in aqueous suspensions is studied using the methods of absorption spectroscopy, electron spin resonance spectroscopy (ESR), X-ray diffraction, and spectrophotometry of solutions of singlet oxygen chemical traps—histidine in combination with p-nitrosodimethylaniline. Two new variants are proposed for obtaining aqueous suspensions of particles of solid-phase fullerene whose structures are disordered and whose degrees of amorphization are 67 and 40%, respectively. It is shown that an increase in the disorder of the structure of particles in suspensions and a decrease in their average size facilitate an increase in the formation efficiency of singlet oxygen by solid-phase fullerene presumably due to an in increase in the concentration of surface localized excitons.

Laboratory plasma experiments have demonstrated their prime importance as essential and powerful tools for modeling and understanding many basic plasma physics phenomena as well as space and astrophysical processes. This review discusses laboratory experiments devoted to electron beam interaction with waves in magnetized plasmas, in physical conditions relevant to natural space phenomena or controlled experiments involving artificial beam injection. The study of physical processes governing the conversion of beam kinetic energy into whistler emission as well as the efficiency and the directive patterns of the resulting wave radiation is of great importance not only for basic and space plasma physics, but also for various applications. In particular, recent experimental results on the interaction of a modulated electron beam spiralling in a magnetized plasma with the whistler waves that it radiates through various excitation mechanisms are presented. Whistler emission through resonant Cherenkov and cyclotron processes has been demonstrated and characterized for the first time in a laboratory experiment when injecting a modulated electron beam into a magnetoplasma. By choosing beam and plasma parameters, these emissions could be separated from transition radiation due to interactions in the region of the beam source. Experimental investigation of fast processes produced by the injection of a single short-time current pulse of the order of 10 ns is also described, demonstrating different types of transient plasma responses depending on the nature of the whistler excitation mechanism involved.

Transition radiation from the zone of injection of a modulated electron beam spiralling into a magnetoplasma has been identified as whistler waves propagating quasiparallel to the external magnetic field. The characteristics of the radiation are similar to the emission by localized sources, such as loop antennas and electric dipoles: resonance-cone structures at low plasma densities and energy flow along the external magnetic field at higher densities, with a diverging radiation pattern and with whistler phase velocities inversely proportional to the plasma frequency. These studies should contribute to a wider understanding of the physical processes connected with the injection of charges in a magnetoplasma – either from a gun on board a spacecraft or in a plasma chamber – and thus allow the determination of appropriate radiator characteristics in order to control, to some extent, plasma perturbations and wave emission in the region of the injector.

When injecting an electron beam with a significant pitch-angle in a magnetoplasma, one has to take care that the parallel velocity of the electrons measured in the plasma does not only depend on the acceleration potential between the anode and the cathode of the electron gun, but also on the amplitude of the ambient magnetic field. The latter can play an important role when the actual acceleration distance of electrons in the gun vicinity, determined partly by collective processes that lead to potential modification in the gun environment, is large enough. Consequently, the actual beam pitch-angle can be noticeably different from the orientation of the electron gun.

Emission of whistler waves through the Cherenkov resonance mechanism has been studied in a laboratory experiment modeling the interaction of a modulated electron beam with a magnetized plasma under conditions relevant to space experiments involving electron beam injection. The characteristics of the emission and the propagation of the radiated whistlers, and namely the features of their directive radiation patterns, have been controlled as a function of the beam and plasma parameters. This beam radiation process can be distinguished from another mechanism of wave emission, the nonresonant transition radiation from the beam injection point, owing to adequate choices of the physical conditions.

In the frame of laboratory studies devoted to whistler excitation by a modulated electron beam injected in a magnetoplasma under conditions relevant to space experiments, fast processes have been investigated using the modulated electron beam as a train of short-time current pulses injected in the plasma. Single pulses of duration of the order of τ≃15 ns as well as unmodulated beams with sharp fronts (step functions with rise time of the order of τ≃10 ns) have been injected in the afterglow plasma with an energy of the order of 300 eV. Plasma responses to the fast perturbations are transported by whistler waves in the frequency range ωlh≪1/τ

A study has been carried out to compare the photophysical properties of a water-soluble photosensitizer of porphyrin nature (dimegin) with photosensitizers currently used in medical practice (photoditazin and radachlorin). Results are given for an investigation of the singlet-oxygen generation efficiency by the photosensitizers when they are irradiated by an LED array (radiation wavelength 395–405 nm). The luminescence spectra of the photosensitizers irradiated by an LED (wavelength 465 nm) were investigated, and it is pointed out that dimegin has higher luminescence intensity than photoditazin and radachlorin. A study was carried out of how the block copolymer Pluronic F-127 in a complex with dimegin affects the capability of the latter to generate singlet oxygen.

ALICE is a general-purpose heavy-ion experiment designed to study the physics of strongly interacting matter and the quark-gluon plasma in nucleus-nucleus collisions at the LHC. It currently involves more than 900 physicists and senior engineers, from both the nuclear and high-energy physics sectors, from over 90 institutions in about 30 countries. The ALICE detector is designed to cope with the highest particle multiplicities above those anticipated for Pb-Pb collisions (dN(ch)/dy up to 8000) and it will be operational at the start-up of the LHC. In addition to heavy systems, the ALICE Collaboration will study collisions of lower-mass ions, which are a means of varying the energy density, and protons (both pp and pA), which primarily provide reference data for the nucleus-nucleus collisions. In addition, the pp data will allow for a number of genuine pp physics studies. The detailed design of the different detector systems has been laid down in a number of Technical Design Reports issued between mid-1998 and the end of 2004. The experiment is currently under construction and will be ready for data taking with both proton and heavy-ion beams at the start-up of the LHC. Since the comprehensive information on detector and physics performance was last published in the ALICE Technical Proposal in 1996, the detector, as well as simulation, reconstruction and analysis software have undergone significant development. The Physics Performance Report (PPR) provides an updated and comprehensive summary of the performance of the various ALICE subsystems, including updates to the Technical Design Reports, as appropriate. The PPR is divided into two volumes. Volume I, published in 2004 (CERN/LHCC 2003-049, ALICE Collaboration 2004 J. Phys. G: Nucl. Part. Phys. 30 1517-1763), contains in four chapters a short theoretical overview and an extensive reference list concerning the physics topics of interest to ALICE, the experimental conditions at the LHC, a short summary and update of the subsystem designs, and a description of the offline framework and Monte Carlo event generators. The present volume, Volume II, contains the majority of the information relevant to the physics performance in proton-proton, proton-nucleus, and nucleus-nucleus collisions. Following an introductory overview, Chapter 5 describes the combined detector performance and the event reconstruction procedures, based on detailed simulations of the individual subsystems. Chapter 6 describes the analysis and physics reach for a representative sample of physics observables, from global event characteristics to hard processes.

The river runoff is regulated by the construction of water reservoirs, dams, and other hydrotechnical construction for allocation of water from riverbeds. These activities have a strong affect on the environment such as flooding of large areas of fertile land in river valleys, swamping, development of salination and erosion of water reservoir banks. The paper discusses negative effects caused by the Kapchagai Water Reservoir constructed on the Ili River to the environment in Kazakhstan, and in the Kiev Water Reservoir build up on the Dnepr River in the Ukraine.

Systematic observations of the whole celestical halfsphere radiation at centimeter and decimeter wavelength ranges have been carried out since 1970. Simultaneous observations at four locations in the Soviet Union are made to filter out cosmic signals from a background of all kinds of local noise. The existence of a global sporadic radiation apparently arising near the Earth was discovered. Conclusions are reached concerning the optimal conditions for scanning the cosmos in order to detect sporadic radiation from technically developed extraterrestrial civilizations.

The uniformity of the properties of the radio-emission bursts over a large territory and the dependence of their characteristics on manifestations of solar activity lead to the following conclusions.

Context. Colliding collisionless shocks appear across a broad variety of astrophysical phenomena and are thought to be possible sources of particle acceleration in the Universe. Aims. The main goal of our experimental and computational work is to understand the effect of the interpenetration between two subcritical collisionless shocks on particle energization. Methods. To investigate the detailed dynamics of this phenomenon, we performed a dedicated laboratory experiment. We generated two counter-streaming subcritical collisionless magnetized shocks by irradiating two Teflon (C2F4) targets with 100 J, 1 ns laser beams on the LULI2000 laser facility. The interaction region between the plasma flows was pre-filled with a low-density background hydrogen plasma and initialized with an externally applied homogeneous magnetic field perpendicular to the shocks. We also modeled the macroscopic evolution of the system via hydrodynamic simulations and the microphysics at play during the interaction via particle-in-cell (PIC) simulations. Results. Here, we report our measurements of the plasma density and temperature during the formation of the supercritical shocks, their transition to subcritical, and their final interpenetration. We find that in the presence of two shocks, the ambient ions reach energies around 1.5 times of those obtained with single shocks. Both the presence of the downstream zone of the second shock and of the downstream zone common for the two shocks play a role in the different energization: the characteristics of the perpendicular electric fields in the two areas indeed allow for certain particles to continue being accelerated or, at least, to avoid being decelerated. Conclusions. The findings of our laboratory investigation are relevant for our understanding of the energy distribution of high-energy particles that populate the interplanetary space in our solar system and the very local interstellar medium around the heliopause, where observations have indicated evidence of subcritical collisionless shocks that may eventually go on to collide with one another.