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A study of the degradation profiles of drugs based on recombinant monoclonal antibodies under stress conditions made it possible to determine the dynamics and mechanisms of degradation processes, to identify drug degradation products, and to reveal differences in the stability of biosimilar drugs for relatively short times. A strategy for accelerated (35 d) stability assessment under stress conditions of the original product Soliris® (Switzerland) and its biosimilar PRK-001 (Russia) was proposed. Their degradation profiles after exposure to extreme pH, oxidative stress, and UV radiation were studied. Antibody fragments were analyzed using size-exclusion chromatography, capillary isoelectric focusing, electrophoresis, and mass spectrometry. Both products showed similar degradation profiles and similar changes in isoform contents.

A series of silica mesoporous molecular sieves SBA-15 with a 7.7 ± 0.8 nm pore diameter, the surface of which is hydrophobized with methylsilyl groups, and polymethylsiloxane derivatives with a 1.6 ± 0.8 nm pore diameter were obtained. These sieves are characterized by X-ray phase analysis, adsorption of nitrogen at 77 K and water at 293 K, as well as IR spectroscopy. It is established that there is a significant resistance to water intrusion (absorption) only in the case of substances characterized by the nitrogen adsorption potential value ∆μ0 ≤ 6.4 kJ/mol. The studied systems can be used as “molecular springs” in shock load damping devices due to their functional properties.

We studied the regularities of distribution of siderophile elements, including platinum group elements (PGE), in rock and in sulfides from Archean (2814 ± 51 Ma) peridotites collected in a fragment of deformed dike within the Bug granulite complex, Ukrainian Shield. In comparison with the primitive mantle, the studied rocks are enriched in Rh, Pd, Ni, Fe, and Co, and are characterized by low concentrations of other PGE. Sulfides are represented by a high-temperature variety of pentlandite and a small amount of chalcopyrite, with an inhomogeneous PGE distribution in them. Pd/Ir ratio typical of superchondrite is revealed for rocks and some sulfides. It is supposed that enrichment in Pd was not resulted from fractionation, but was rather related to mantle metasomatism. Saturation of the melt with sulfides and liquation process were favored by contamination of harzburgite with the host gneissic enderbite and fractionation of olivine. Solid sulfide solutions formed from sulfide melts at temperatures close to the crystallization temperature of magnesium phlogopite from a silicate melt.

As a result of the breeding process, there are two main types of flax (Linum usitatissimum L.) plants. Linseed is used for obtaining seeds, while fiber flax is used for fiber production. We aimed to identify the genes associated with the flax plant type, which could be important for the formation of agronomically valuable traits. A search for polymorphisms was performed in genes involved in the biosynthesis of cell wall components, lignans, fatty acids, and ion transport based on genome sequencing data for 191 flax varieties. For 143 of the 424 studied genes (4CL, C3′H, C4H, CAD, CCR, CCoAOMT, COMT, F5H, HCT, PAL, CTL, BGAL, ABC, HMA, DIR, PLR, UGT, TUB, CESA, RGL, FAD, SAD, and ACT families), one or more polymorphisms had a strong correlation with the flax type. Based on the transcriptome sequencing data, we evaluated the expression levels for each flax type-associated gene in a wide range of tissues and suggested genes that are important for the formation of linseed or fiber flax traits. Such genes were probably subjected to the selection press and can determine not only the traits of seeds and stems but also the characteristics of the root system or resistance to stresses at a particular stage of development, which indirectly affects the ability of flax plants to produce seeds or fiber.

The Sr isotope characteristic of carbonate rocks in the Central Azov Group has been reported (0.70322–0.70352), the Nd model age of silicate sediments has been calculated (2.34–2.31 Ga), and the U–Pb age of trondhjemites (2052 ± 5 Ma) breaking through carbonates was determined. According to the data obtained, the marine sedimentary cover of the Azov block making up the Early Precambrian Sarmatia Continent was formed in the Early Paleoproterozoic 2.23–2.34 Ga ago.

MIC and minimum biofilm bactericidal concentration (MBBC) values of eravacycline against 185 staphylococci from periprosthetic joint infections were determined. Staphylococcus aureus had MICs of ≤0.25 μg/ml. MICs for methicillin-susceptible and -resistant Staphylococcus epidermidis were ≤1 and ≤2 μg/ml, respectively. S. aureus and S. epidermidis MBBC 50 and MBBC 90 values were 8 and 16 μg/ml for each, showing poor anti-staphylococcal biofilm activity using the method studied.

Qualitative indicators of roasting products are fully determined from the technological mode parameters change in roasting carbon products campaign. Dividing the roasting campaign into the key stages and studying the dependence of the furnace temperature fields as a function of the technological parameters, and their rational use makes it possible to lower the defective products output. Therefore, it is important to model these processes taking into account the maximum number of factors that will minimize the time and cost of the finished products production; this modeling being an important stage in the development of a process control system that provides the output of finished products of the appropriate quality. On the basis of the numerical simulation method, the influence of the initial temperature of the air, which is fed for fuel combustion into the chamber «under the fire», on the temperature mode of products roasting has been carried out. It has been shown that the change in the initial air temperature substantially affects the furnace temperature fields. The regularities in the change of the mean value of the temperature drop across the blanks under different operating conditions were revealed. The main attention of the research was paid to the homogeneity of the temperature field of blanks, which significantly affects their quality. The results of the study showed that an increase in the initial temperature leads to the possibility of reducing the cost of natural gas, which improves the technical and economic parameters of the process, but causes an increase in temperature variations in the billets, which can lead to a defect of finished products. From the results of this study, the task for further research is to develop an algorithm for determining the optimal initial air temperature, taking into account both the energy efficiency conditions of the roasting process and the provision of the required quality of finished products

The concentrations of polycyclic aromatic hydrocarbons (PAH), total carbon (TC), total organic carbon (TOC), total nitrogen (TN) and dissolved inorganic nitrogen (DIN) in water and sediment...

Qualitative management of the process of baking carbon products by changing the parameters of the technological routine allows achieving a lower output of defective products. The study of the main stages of the baking process is characterized by the multifactor of the model and the nonlinearity of the connection between the temperature field and the technological parameters. Therefore, it is important to model these processes taking into account the maximum number of factors that will minimize the time and cost of finished products. The study of the influence of excess air on the temperature regime of the chamber of the baking furnace while working «under fire» was carried out. The regularities of change in temperature drop across the workpieces under different modes of conducting the process are analyzed. Characterized areas of the furnace with minimum and maximum temperatures are detected. The quality of the process of combustion of fuel through the mass fraction of combustion products is investigated. The study of the effect of excess air flow on the temperature regime of the operation of one chamber of the baking furnace is carried out. The temperature of carbon blanks and gas medium was investigated in two operating modes: with excess air a = 1.1 and a = 1.2. The main attention of the research was paid to the issues of homogeneity of the temperature field of blanks, which significantly affects their quality. It is shown that it is advisable to maintain an excess air flow at the lower limit of permissible values.

We present results of study of organic matter in the coastal and bottom sediments of the Laptev Sea (Buor-Khaya Gulf). The study has shown the regularities of organic-matter distribution in the shelf zone adjacent to the glacial coast. The coast composed of a glacial rock complex supplies the largest amount of organic material to the sea as compared with other types of the coast. The average content of organic matter in these strata is ~2–3%. The bottom sediments of the shallow littoral zone are significantly depleted in organic carbon (0.1–0.3%) as a result of their active rewashing and the transition of finely dispersed material (mainly organic one) toward the deep sea zones. The content of organic carbon in the bottom sediments increases to 1–2% as the sea deepens to 7–10 m at 5–12 km from the coast. There are frequent local anomalies of organic-carbon contents (up to 4–5%) in the deltaic zones of the sea. The highest contents of organic carbon (up to 3%) have been found in the recent marine sediments in the central, relatively deep zones of the bays.

The object of research is the process of formation of carbon products. The production of carbon products is characterized by considerable resource and energy intensity, therefore the actual task is to increase the efficiency of this production by introducing the optimum operating modes of its component technological processes. One of the main technological processes in the production of carbon products is the process of their formation by squeezing of the electrode mass through a mouthpiece of the corresponding shape in a hydraulic press. All inherited properties that determine the quality of finished products are laid at the stage of pressing the electrode blanks The analysis of the existing control systems for the process of formation of carbon products shows that the formation process is a typical cyclic process. For such processes, the control task is, as a rule, to implement such controls that would ensure that one or more output variables are tracked by a predetermined path of motion, which is repeated from cycle to cycle. A new control system is proposed that provides for iterative learning control in formation of the electrode mass by squeezing through a mouthpiece of the corresponding shape in a hydraulic press. The corresponding ILC algorithm is proposed. Thanks to this solution, a high quality control is provided in the absence of initial uncertainties and external disturbances.

The objective of the present study was to assess the levels of Se, as well as other essential and toxic trace elements in wheat grains and traditional Roti-bread from whole-grain flour in a seleniferous area of Punjab (India) using inductively-coupled plasma mass-spectrometry. Wheat grain and bread selenium levels originating from seleniferous areas exceeded the control values by a factor of more than 488 and 179, respectively. Se-rich wheat was also characterized by significantly increased Cu and Mn levels. Se-rich bread also contained significantly higher levels of Cr, Cu, I, Mn, and V. The level of Li and Sr was reduced in both Se-enriched wheat and bread samples. Roti bread from Se-enriched wheat was also characterized by elevated Al, Cd, and Ni, as well as reduced As and Hg content as compared to the respective control values. Se intake with Se-rich bread was estimated as more than 13,600% of RDA. Daily intake of Mn with both Se-unfortified and Se-fortified bread was 133% and 190% of RDA. Therefore, Se-rich bread from wheat cultivated on a seleniferous area of Punjab (India) may be considered as a potent source of selenium, although Se status should be monitored throughout dietary intervention.

Flax (Linum usitatissimum L.) is a multipurpose crop which is used for the production of textile, oils, composite materials, pharmaceuticals, etc. Soil acidity results in a loss of seed and fiber production of flax, and aluminum toxicity is a major factor that depresses plant growth and development in acid conditions. In the present work, we evaluated gene expression alterations in four flax genotypes with diverse tolerance to aluminum exposure. Using RNA-Seq approach, we revealed genes that are differentially expressed under aluminum stress in resistant (Hermes, TMP1919) and sensitive (Lira, Orshanskiy) cultivars and selectively confirmed the identified alterations using qPCR. To search for differences in response to aluminum between resistant and sensitive genotypes, we developed the scoring that allowed us to suggest the involvement of MADS-box and NAC transcription factors regulating plant growth and development and enzymes participating in cell wall modifications in aluminum tolerance in flax. Using Gene Ontology (GO) enrichment analysis, we revealed that glutathione metabolism, oxidoreductase, and transmembrane transporter activities are the most affected by the studied stress in flax. Thus, we identified genes that are involved in aluminum response in resistant and sensitive genotypes and suggested genes that contribute to flax tolerance to the aluminum stress.

Field observations showed that the characteristics of chemical composition of waters and the development of plankton algae in the lakes within the delta of the Selenga river are determined by their flowage. The most open Lake Nekipelovskoe communicates with the Selenga outlets throughout a year, and Lake Zavernyaikha only at the period of an open channel. Lake Semenovskoe and Lake Khlystov Zaton are located in the islands and are isolated from the outlets. According to composition of main ions, the lakes under investigation refer to the hydrocarbonate class, the calcium group. The sum of ions in the water of Lake Nekipelovskoe approaches the one in the Selenga (86−221 mg/dm3), and the highest sums of ions were recorded in the wintertime in the lakes isolated from the outlets (446−743 mg/dm3). The lakes of the delta are characterized by a high trophicity. The maximum concentrations of total phosphorus in Lake Nekipelovskoe and Lake Zavernyaikha were 68 and 122 μg mg/dm3, and in Lake Semenovskoe and Lake Khlystov Zaton −0.8 and −0.63 μg mg/dm3, respectively. The most intense development of algae is observed in Lake Zavernyaikha, which is due to the high population of Baikal endemics. Lake Zavernyaikha showed a close negative correlation between the concentration of NO3−, mineral phosphorus and phytoplankton biomass; the correlation coefficient was −0.8 and −0.63, respectively. The lakes exhibited increased contents readily hydrolysable organic matter, and a decrease in dissolved oxygen concentration in winter; hydrogen sulfide was repeatedly recorded in Lake Khlystov Zaton. The water quality in the lakes during the springtime varies from “quite clean” to “weakly polluted”; at low-water periods, especially in winters, it can drop to the category of “exceedingly dirty”. The water quality of the Selenga can be influenced by the lakes during spring floods when material accumulated during the wintertime is transported to the river outlets and further to Lake Baikal.

Background Perirosthetic joint infections (PJIs) are costly and difficult to treat. The most common causes of PJIs are Staphylococcus aureus and Staphylococcus epidermidis. Eravacycline is a newer tetracycline with promising activity against Gram-positive and negative bacteria which is approved for treatment of complicated intraabdominal infections. Here, the in vitro activity of eravacycline was assessed against bacteria associated with PJI. Methods 185 staphylococcal isolates, including 38 methicillin-resistant S. aureus (MRSA), 64 methicillin-susceptible S. aureus (MSSA), 62 methicillin-resistant S. epidermidis (MRSE) and 21 methicillin-susceptible S. epidermidis (MSSE) strains were studied. Minimum inhibitory concentrations (MICs) were determined according to Clinical and Laboratory Standards Institute guidelines (range of 0.06-64 µg/ml tested). Results were analyzed using susceptible breakpoints from EUCAST (≤0.25 µg/ml) and the FDA (≤0.06 µg/ml). Minimum biofilm bactericidal concentrations (MBBCs) were determined using a modification of the Calgary biofilm method. Briefly, biofilms were formed on pegged lids in trypticase soy broth, after which the pegged lids were rinsed in phosphate buffered saline (PBS), transferred to a plate containing dilutions of eravacycline in cation-adjusted Mueller Hinton broth (CAMHB) and incubated for 20-24h. Finally, the pegged lids were again rinsed in PBS and transferred to a plate containing CAMHB and incubated for 24h. The MBBC was the lowest concentration with no visible growth. Results MIC50/90 (range) in µg/ml for MRSA, MSSA, MRSE, and MSSE were 0.125/0.125 (≤0.06-0.25), ≤0.06/0.125 (≤0.06-0.25). 0.125/1 (≤0.06-2), and 0.25/1 (≤0.06-1), respectively. Using the EUCAST susceptible breakpoint, 100% of isolates would be considered susceptible, whereas only 54% would be considered susceptible using the FDA breakpoint. MBBC50/90 (range) in µg/ml for MRSA and MSSA were both 8/16 (4-16); for MRSE and MSSE, the values were 4/16 (2-32) and 8/16 (2-32), respectively. Conclusion Our data suggest that the FDA susceptible breakpoint may need re-evaluation. Eravacycline has low anti-staphylococcal biofilm activity. Disclosures Robin Patel, MD, Accelerate Diagnostics (Grant/Research Support)CD Diagnostics (Grant/Research Support)Contrafect (Grant/Research Support)Curetis (Consultant)GenMark Diagnostics (Consultant)Heraeus Medical (Consultant)Hutchison Biofilm Medical Solutions (Grant/Research Support)Merck (Grant/Research Support)Next Gen Diagnostics (Consultant)PathoQuest (Consultant)Qvella (Consultant)Samsung (Other Financial or Material Support, Dr. Patel has a patent on Bordetella pertussis/parapertussis PCR issued, a patent on a device/method for sonication with royalties paid by Samsung to Mayo Clinic, and a patent on an anti-biofilm substance issued.)Selux Dx (Consultant)Shionogi (Grant/Research Support)Specific Technologies (Consultant)

This paper reviews the chemical composition of 12 Antarctic lakes at offshore Russian stations in the period of seasonal work 55 and 58 RAE (Russian Antarctic Expedition) in December-January 2009-2010 and 2013-2014. Results of hydrochemical analyses of lake water, as well as their classification by ion composition, organic matter content, and mineralization, are presented in this paper. Low-level content of microelements in lake waters are also presented. Enrichment factors of lake waters in relation to ocean water were calculated and direct stratification of water from the surface to the bottom of Lake Progress was identified.

A nickel-chelate affinity chromatography has been used to isolate fused proteins of Hsp70-E7 from yeast lysate at the initial stage of the work. The low purity of the monomeric Hsp70-E7 in the final fraction was associated with the occurrence of dimeric and tetrameric forms of the target protein and low-molecular impurities. A modification of the purification procces by the addition of reduced L-glutathione to inhibit the formation of unwanted disulfide bonds permitted to increase the purity of the target protein by reducing the content of the oligomerized products. Further changes in the purification protocol, namely the reduction of hydrophobic interactions by the introduction of glycerol, significantly reduced the amount of low-molecular impurities. For a finer purification of E7-HSP70, a two-stage process of anion-exchange chromatography that made it possible to effectively eliminate low-molecular impurities was used. The assessment of the final material by electrophoresis under non-reducing conditions showed that the purity of the monomeric forms of either of the proteins was higher than 95%.

The sources of polycyclic aromatic hydrocarbons (PAHs) and sources of water that deliver PAHs to an investigated river were apportioned using an end-member mixing approach. The identification of sources and tracers was based on bounding the samples by end-member sources on the mixing diagram using coordinates of source tracer concentrations. The sums of PAHs with the same molecular weight were used as PAH source tracers, and the dissolved organic carbon to base cations ratio was used as a tracer for water sources. The source contributions were evaluated by solving systems of linear equations. Most of the water samples were bound by a triangle formed by wood combustion, oil-fired boilers, and aluminum smelters in the mixing space defined by the concentrations of the principal mass 178 and 228 PAHs. There were notable seasonal variations in the PAH source contributions at each sampling site due to different contributions of groundwater, surface flow, and interflow to stream water. The differences in the PAH source contributions among sites were due to both different proportions of the flow components and different positions of the sites relative to the emission sources. Most of the bottom sediment samples were bound by a triangle formed by the same sources, but in the mixing space defined by the principal mass 252 and 276 PAHs. There were no spatial or temporal differences in the PAH source proportions among the samples because the PAH composition of the bottom sediments at each location represents the time- and space-weighted average of all the sediment loads from upstream.

A microwave digestion procedure with the use of specially designed autoclaves and a domestic microwave oven is proposed for the mass-spectrometric determination of the elemental composition of bottom sediments. The throughput of sample preparation in routine analysis was considerably increased because of the elimination of a purification step. Reaction mixture compositions and microwave digestion conditions were chosen to reach complete decomposition (within the limits of error of semiquantitative ICP MS analysis) of Baikal bottom sediments with respect to the majority of elements. It was found that the procedure is unsuitable for the determination of Sn, Zr, Nb, Hf, As, and Sb. The approximate concentrations of elements in a BIL-1 certified reference material of Baikal bottom sediments were found: Tl, 0.52 ± 0.16 ppm; Bi, 0.33 ± 0.10 ppm; I, 14.3 ± 4.3 ppm; Cd, 0.31 ± 0.09 ppm; and Pb, 0.24 ± 0.07 ppm.

A simple, reliable, and high-performance method has been proposed for direct determination of the isotopic composition of authigenic uranium in silica lacustrine sediments. The method is based on studying the kinetics of the selective extraction of authigenic uranium from sediments with weak solutions of ammonium hydrocarbonate followed by the ICP-MS analysis of the nuclides. To estimate the contamination of authigenic uranium by terrigenous one, the contents of 232Th and some other clastogenic elements in the extracts were measured simultaneously. The selectivity of extraction of authigenic uranium from the sediments treated with a 1% NH4HCO3 solution appeared to be no worse than 99%. The method was used to analyze the isotopic composition of authigenic uranium at several key horizons of a core dated before. The measurements directly prove that the 234U/238U values in Baikal water varied depending on climate, which contradicts the previous statements. The measured 234U/238U ratios in paleo-Baikal water match the values reconstructed from isotopic data for total uranium in the sediments on the supposition that the U/Th ratio is constant in the terrigenous part of the sediment. Direct experimental determination of total and authigenic nuclides in sediments enhances the potentiality of the method for absolute 234U-230Th dating of carbonate-barren lacustrine sediments, including those from Lake Baikal, within the intervals corresponding to the periods of glaciation, where the sediments contain a large fraction of terrigenous component. Given the fractions of terrigenous and authigenic uranium are accurately determined, we have an opportunity to study the variability of the sources of terrigenous matter and to refine the previous model for reconstructing the climate humidity in East Siberia.

The density of states for InAs/GaAs quantum dot (QDs) bi-layer arrays placed between two AlGaAs barriers is studied by means of photoluminescence (PL) excitation, resonant PL and time-resolved PL. By varying the excitation energy from above the AlGaAs band gap to values resonant with the QD energies, the energy of states in each layer including the wetting layer, corresponding localized states, defect states and QD states is determined. The creation of asymmetric pairs of quantum dots caused by interlayer coupling is traced starting from the case of weakly correlated systems represented by bi-layer QD arrays with a thick GaAs spacer layer (50 monolayers) to the case of fully correlated systems with a GaAs spacer (30 monolayers). Different mechanisms of carrier relaxation related to the density of states below the barrier and interlayer coupling are explored.

Quantum well micro-Hall devices based on uniformly Si-doped Al 0.3 Ga 0.7 As/GaAs and Si-δ-doped Al 0.3 Ga 0.7 As/GaAs/In 0.3 Ga 0.7 As heterostructures are investigated as function of electric field and compared in terms of sensitivity and noise properties. The data show that at high electric fields, doped-channel quantum well devices are advantageous over high-mobility structures and that the use of pseudomorphic InGaAs results in better performance than does GaAs. A maximal signal-to-noise sensitivity (SNS) of 138 dB T −1 is achieved in a 10 μm ×10 μm device at 300 K, at frequency of 100 kHz and bandwidth of 1 Hz. This performance corresponds to a lowest detection limit of 127 nT Hz −1/2 , with no degradation for electric fields up to 2.4 kV cm −1 ; these values represent the best reported at such high electric fields. Furthermore, our results suggest that a signal-to-noise sensitivity of 160 dB T −1 and a lowest detection limit of 10 nT is achievable in doped-channel structures.

This report presents a PC-based program for solution gas dynamics and heat exchange mathematical tasks in fuel assemblies of the fast-neutron nuclear reactors. A fuel assembly consisting of bulk heat-generating elements, which are integrated together by the system of supply and pressure manifolds, is examined. Spherical heat-generating microelements, which contain nuclear fuel, are pulled into the heat-generating elements. Gaseous coolant proceed from supply manifolds to heat-generating elements, where it withdraws the nuclear reaction heat and assembles in pressure manifolds.

Shubnikov-de Haas oscillations of magnetoresistance are studied in semimagnetic quaternary solid solutions of n-Hg1-x-yCdxMnyTe (x 100 meV. The effect of the a value reduction is found to be the most pronounced near the semimetal-semiconductor transition and probably depends on the value of spin-orbit splitting in semimagnetic semiconductors. It is assumed to be connected with the growth of p-d exchange admixing due to the small Eg value.

Narrow-gap ( E g ≤50 meV) semi-magnetic n -Hg 1− x − y Cd x Mn y Te ( x y ≤0.028) single crystals have been studied by means of oscillatory magneto-resistance. It has been found that the Dingle temperature T D , defined by a non-thermal electron scattering, is of comparatively high value, T D ∼9 K, for the compositions 0≤ y y >0.025. Strong reduction of the T D value is detected for the composition 0.01 y 1− x Cd x Te material favored by manganese doping.

Photoluminescence (PL) of self-organized quantum dots (QDs) in bilayer InAs/GaAs structures is studied with a fixed seed layer and spacer, but variable second-layer coverage. Careful line shape analysis reveals modulation in the high-energy tail of the seed-layer PL spectrum. The oscillation-like behavior is reproducible with variations in both the temperature and optical excitation energy. These oscillations are attributed to carrier relaxation through inelastic phonon scattering from the wetting layer to the QD excited states.

Time-resolved photoluminescence (PL) from InAs/GaAs quantum dots with a bimodal size distribution is used to investigate the dynamic carrier-transfer processes which couple transfer between similarly sized quantum dots and between quantum dots in different size categories. The relationship between the decay time and the emission energy appears staircaselike and the energetic positions of the steps as well as the shape can be correlated to the shape of the steady-state PL emission through a rate-equation theory. These results show how transient PL can be used to investigate the dynamics of carrier transfer in quantum-dot systems.

The mixed state of the YBaCu2O6.9 superconducting ceramics is investigated by neutron depolarization (ND). The magnetic flux penetration into superconductor's granules can be described in terms of Bean's critical state model. The field and temperature dependence of the average angle of the vortex line deflection from the direction of the applied magnetic field are determined. In particular, this angle is zero atT/T c ∼0.5 andH/H c2∼0.015, which is at the sameT/T c nearH/H c2∼0.017 for the metalloceramic SnMo6S8 superconductor. The latter is also studied in the present work for comparison with the YBa2Cu3O6.9 sample. TheseH/H c2 are far below the corresponding values ofH/H c2 for Nb, Nb−Ta. The creep of the flux line misalignments from the applied field direction is examined.

Concentrations of (137)Cs and stable Cs were determined in plant, mushroom, lichen and soil samples collected at two forest sites with different contamination levels in Belarus in 1998. The concentration of (137)Cs in soil was the highest in near-surface organic layers (Of and Oh horizons) and decreased with depth in the mineral layers, whereas the concentrations of stable Cs were almost constant in the soil profile. The levels of (137)Cs and stable Cs in biological samples varied depending both on the species and the plant part sampled. Even though different species and parts of the same species were included, the concentration ratios of (137)Cs to stable Cs were fairly constant for samples collected at the same forest site, and were in the same order of magnitude as the (137)Cs to stable Cs ratios for the organic soil layers. This finding suggests that (137)Cs, mainly deposited on the forest ecosystems from the Chernobyl accident in 1986, was well mixed with stable Cs within the biological cycle in the forest ecosystems by 1998. The transfer factor for each biological sample of (137)Cs was almost the same as that of stable Cs, if they were calculated based on the concentrations in the Of + Oh layer. This suggests that the stable-Cs-based transfer factor could be used as equilibrium transfer factor of (137)Cs for different types of biological samples in the forest.

Pseudomorphic strained-layer AlxGa1-xAs/InyGa1-yAs/GaAs heterostructures have been studied by means of photoluminescence (PL) and Raman scattering. It is established the correlation between the PL line shape changes and the Raman spectra modification when the QW width is below the critical layer thickness (CLT) estimated to be of 25 nm for y = 0.1. The PL feature observed for the InGaAs QW width equal to 20 nm as extremely narrow exciton-like peak with the FWHM equal 1.5 meV at low temperature (T = 6K) transforms into broad band of the FWHM equal 16 meV when the QW width reaches the value about of 12 nm. The PL line shape broadening is accompanied by the modifications of Raman spectra. A new line arising at the spectral position v = 160 cm-1 is assigned to impurity-induced longitudinal acoustic optical mode of InyGa1-yAs. The changes observed in optical spectra are related to generation of defects in the under-CLT region.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

One of the largest environmental polluters in Chapaevsk (Samara Region, Russia) is the Middle Volga chemical plant. From 1967 to 1987, it produced hexachlorocyclohexane (lindane) and its derivatives. Currently, it produces crop protection chemicals (liquid chlorine acids, methyl chloroform, vinyl chloride, and some other chemicals). Dioxins were detected in air (0.116 pg/m3), in soil (8.9-298 ng/kg), in the town's drinking water (28.4-74.1 pg/liter), and in the cow's milk (the content of 2,3,7,8-TCDD was 17.32 pg TEQ/g fat). The mean content of dioxins in seven pooled samples of human milk (40 individual trials) was 42.26 pg TEQ/g fat, in four female workers' blood samples -412.4 pg TEQ/g fat, in six residents blood samples (those who lived 1-3 km from the chemical plant) -75.2 pg TEQ/g fat, in four residents' blood samples (5-8 km from the plant) -24.5 pg TEQ/g fat. To assess cancer risk and reproductive health status, official medical statistical information was used. In general, the male cancer mortality observed rate in Chapaevsk is higher than expected. The SMR is higher for lung cancer 3.1(C.I. 2.6-3.8), urinary organs 2.6(C.I. 1.7-3.6). Chapaevsk women have a higher risk overall due to breast cancer 2.1(C.I. 1.6-2.7) and cervix cancer 1.8(C.I. 1.0-3.1). The incidence rates were higher for lung cancer in males and for female breast cancer in all age groups compared to Russia and Samara Region in 1998. Significant disruptions in reproductive function were detected. The mean frequency of spontaneous abortions in the last seven years was statistically higher 24.4% in Chapaevsk (compared to other of the towns region). The average rate of premature labor was 45.7 per 1000 women in Chapaevsk that is significantly higher than in most Samara Region towns. The frequency of newborns with low birth weight was 7.4%. In Russia and in most of the Samara Region towns, this rate is lower (6.2-5.1%) but not statistically different. For the determination of congenital morphogenetic conditions (CMGC), 369 children born between 1990 and 1995 were examined. The average number of CMGC per child was significantly higher, 4.5 for boys and 4.4 for girls. The first results indicated serious disruptions associated with high dioxin levels in human milk and blood in Chapaevsk. We suggest that Chapaevsk is an incredibly interesting site for further environmental-epidemiological research to assess the impact of dioxins on human health.

Peculiar mechanism of carrier transfer, excitonic trapping, from quantum well (QW) states to quantum dot (QD) states is clearly observed for the intentionally designed strained InAs:In0.3Ga0.7As∕GaAs QD:QW structure. This transfer occurs very efficient at low excitation densities and low temperatures and explains the excitation density and nonmonotonic temperature dependences of the QW photoluminescence.

Temperature-dependent photoluminescence is investigated in bilayer InAs∕GaAs quantum dot structures with constant InAs deposition θ1 in the seed layer, but variable deposition θ2 in both the second layer and the GaAs spacer layer. It is shown that interlayer coupling, leading to the formation of asymmetric quantum dot pairs, strengthens the high-temperature photoluminescence and strongly influences carrier relaxation channels. We report that radiative recombination and carrier capture efficiency by the quantum dots in the second layer can be tailored using the deposition θ2 and the GaAs spacer thickness.

This paper determines the detonation parameters of several compounds by the method of obstacles by using precision optical instruments, as described; then proposes a new approach that permits the separation of the Jouguet state from the chemical transformation zone by the method of weak overcompression in the case of detonation. The detonation regimes of retarded composites are also determined. Finally, five fundamental deductions drawn from the experiments are given.

Experimental information obtained on laboratory charges of finite length stand in some doubt. In the present work, using precision optical recordings, the applicability of the steady model to short charges is shown, the sources of error in the ''free-surface'' method are analyzed, and the results are interpreted within the framework of classical concepts. The experimental results are completely explained from the viewpoint of the hydrodynamic theory of steady detonation and the model of ''growing detonation'' is based on conclusions from experiments that were formulated in a methodologically incorrect manner according to the authors.

The stopped-flow method has been used to study the kinetics of the reactions of the complexes formed by the rare earth elements of the yttrium subgroup and Xylenol Orange with Trilon B. The influence of the acidity of the medium and temperature on the reaction rate has been studied. The rate constants and activation energy for the process have been determined. A reaction mechanism has been proposed.