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A reflectometry station has been set up in 2013 near Ny‐Ålesund, Svalbard, at 78.9082°N, 11.9031°E. The main goal of the setup is to resolve the spatial and temporal variations in snow and ice cover, based on reflection power observations at grazing elevations. In this study, we develop a method to map the recorded signal power to the main reflection contributions while also discussing the spatial characteristics of the observations. A spectral analysis resolving differential Doppler between direct and reflected signals is presented to identify reflection contributions for a complete year (2014). Strong water reflections are identified with power ratios higher than 70 dB/Hz and constant Doppler shifts of 0.5–0.6 Hz for all elevations. Contributions with ratios higher than 40 dB/Hz can be related to specular land or glacier reflections, for which Doppler shift usually increases with the elevation angle and the distance between reflection point and receiver. Reflections nearby, around 3–5 km, show differential Doppler of 0.4–0.5 Hz, while for reflections farther than 16 km away, Doppler shift is usually larger than 0.8 Hz. Azimuth variations cause cross‐track drift of up to 4° during the observation year. Topography‐induced shadowing of very low lying satellites limits the extent of the monitoring area. However, the amount of satellites tracked daily, up to 30, allows the reflectometry station to constantly record reflections over areas with thick snow cover and glaciers. This offers the possibility to compare the derived reflected power with local meteorological data to resolve snow and ice variations on the area. Doppler shift analysis resolves GNSS reflection events over mountainous topographySignal power is retrieved from multipath signatures for water, land, and glacier reflectionsA range of 14 km and more is detected for grazing angle multipath over land

The annual cycle of modal and mean sea ice thickness was derived from upward looking sonar ice thickness observations (1990–2011) in Fram Strait. The average annual peak‐to‐trough amplitude of the mode of 0.54 m is superimposed on interannual variability with peak‐to‐trough amplitudes of 0.73 m on time scales of 6–8 years, which again is superimposed on a long‐term trend of −0.55 m/decade over the observation period. The long‐term trend is stronger for April than for August, the average months of maximum and minimum modal thickness. As a result, the annual peak‐to‐trough modal thickness amplitude was reduced by 30% between the 1990s and the 2000s. The average annual peak‐to‐trough amplitude of the mean ice thickness of 1.20 m is also superimposed on interannual variability, with as much as 0.97 m thickness change over only 3 years. These two modes of variability are superimposed on a long‐term trend of −0.35 m/decade through the entire data set. In contrast to the modal thickness, the long‐term trend is weaker for the average month of maximum mean thickness (June), than for the average month of minimum (September). Therefore, the annual peak‐to‐trough amplitude of the mean ice thickness increased by 14% between the 1990s and the 2000s. The 1990–2011 thinning trend in ice thickness in Fram Strait displays seasonalityThe annual peak‐to‐trough amplitude of the modal thickness decreased by 30% during 1990–2011The annual peak‐to‐trough amplitude of the mean ice thickness increased by 14% during 1990–2011

The horizontal transfer of genes into the nuclear genome of plants is a rare phenomenon. Currently, the only known examples of this have been described for several Nicotianaand Linariaspecies. In the genome of Linaria dalmatica(L.) Mill a nucleotide sequence sharing 94% similarity with the sequence of the Agrobacterium rhizogenes rolCgene have been described for the first time. The significance of the rolCgene and T-DNA for the evolution of Linariais discussed, as well as their role in the origin of plant species.

This review summarizes information about rol-genes which constitute a part of the T-DNA of Agrobacterium rhizogenes Ri-plasmid. The structure of each of rol-genes, their regulatory sequences, and the possible roles of rol-genes being transferred into the plant are discussed.

Time series (1990–2011) of sea ice thickness observed by moored sonars in the Transpolar Drift in Fram Strait are examined. Contrasting the post‐2007 years against the 1990s, three remarkable changes in the monthly ice thickness distributions are highlighted: (1) The thickness of old level ice (modal thickness) is reduced by 32%, (2) the old ice modal peak width is reduced by 25%, and (3) the fraction of (ridged) ice thicker than 5 m is reduced by 50%. The combined effect on the mean ice thickness is a reduction from an annual average of 3.0 m during the 1990s to 2.2 m during 2008–2011. Most of the thinning took place after 2005–2006. While the old ice modal thickness and peak width show signs of recovery after 2008, the decreasing trend in fraction of ridged ice and mean ice thickness persists until the end of the record in 2011. The ice observed in Fram Strait carries an integrated signal of Arctic change due to the advection of ice from many sites in the Arctic. Based on concurrence in timing, we conclude that much of the thinning quantified here is reflecting recent change in the age composition of the Arctic ice cover toward younger ice. The old level ice remains thin, and as such the ice cover remains preconditioned for new summers of very low sea ice extent. The thickness of old level ice was reduced by 32 % between the 1990s and 2007The relative amount of ridged ice was reduced by 50% between the 1990s and 2007The ice cover remains preconditioned for new summers of minimum sea ice extent

Studying of nitric oxide (NO) dependent mechanisms of regulation of microcirculation in a stomach can provide important diagnostic markers of the development of stress-induced ulcer bleedings. In this work we use a multiscale analysis based on the discrete wavelet-transform to characterize a latent stage of illness formation in rats. A higher sensitivity of stomach vessels to the NO-level in ill rats is discussed.

Abstract: The paper presents the result of investigation of species composition, distribution and degree of resistance to antibiotics of the Enterococcus bacteria in Lake Baikal. It is shown that they live in littoral zones of the lake. In the deep-water part of the lake the studied microorganisms are not found. We isolated 120 strains identified as E. faecium, E. avium, E. faecalis, E. mundii, E. hirae, E. durans, E. gallinarum. On the whole, the strains of enterococcus isolated from Lake Baikal are characterized as antibiotic-sensitive. Nevertheless, the antibiotic-resistant strains of enterococci are found in the studied collection, including those with typical intermediate level of resistance to vancomycin.

Abstract: The rates of changes in the acid-base properties of the sandy-loamy soddy-podzolic soils of fallow lands abandoned for 5, 10, 30, and 63 years were determined. The transformation of the vegetation related to the fallow age has been analyzed. The density of the human-induced topsoil compaction was found to be gradually restored. Mathematical models describing the changes in the acid-base properties of the sandy-loamy soils in the course of the transition from cropland to forest are proposed. The sandy-loamy soils were shown to lose their favorable acid-base properties (gained under cultivation) more slowly than sandy soils do.

Abstract: The scope of stable strontium migration in the light-textured soddy-podzolic soils was determined in columns in a series of simulation experiments. The amount of leached strontium was found to depend on its initial content in the soils, the humus content, and the volume of percolated moisture. The artificial enrichment of soils with strontium increases the losses of this element due to its leaching. However, strontium is not completely removed even upon repeated water percolation.

Abstract: Changes in the content, reserves, and composition of humus in a sandy gleyic iron-humus-illuvial soddy-podzolic soil under intensive, decreasing, and ceased agrotechnical impacts were studied. It was shown that when a well-cultivated soil is removed from economic use, the conditions of humus formation in the former homogeneous plow layer develop differently. A deterioration of the humus status parameters of the layland soil was found as compared to the cultivated soil. It was concluded that, when a soil is removed from economic use, its profile, which was disturbed by the anthropogenic impact, tends to return to the original genetic state. The change in the level of the agricultural practices affected the optical density of the humic acids only slightly, which is indicative of their relative stability under specific soil-forming conditions.

Abstract: A food-related operant reaction was developed in dogs, in which animals had to maintain tonic elevation of the forelimb to hold a bowl while eating with the head tilted towards the feeder. The acquisition of this reaction involved rearrangement of the natural coordination of head and limb movements which appeared at an early stage of training of the dogs. Forelimb elevation was initially accompanied by anticipatory raising of the head, while lowering of the head led to lowering of the elevated limb. Limb elevation could only be maintained in the posture in which the head was raised. The new coordination required for obtaining food, contrary to the innate coordination and consisting of tonic elevation of the limb with the head lowered, could only be achieved as a result of training. Previous studies have established that lesioning of the primary motor cortex (MI) in the hemisphere contralateral to the working limb leads to stable impairment of the learned coordination, with regression to the initial coordination. The present report describes studies of the effects of local lesions of various projection areas of MI on performance of the learned coordination. Dogs which had acquired the learned operant reaction requiring the new head/limb coordination showed impairment only after lesioning of the representation area of the working limb in the MI; lesioning of the representation area of the head had no such effect.

Abstract??A method is developed to determine deeply subcritical states of multiplying media. The method is based on a combination of the?-Rossi method and the multiplying source method with a calculation of the corresponding isotopic-spatial correlation factor.The effective neutron multiplication coefficients in plutonium blocks are measured. The range of determination of the effective multipication coefficients was 0.3?0.45. The measured effective neutron multiplication coefficients in plutonium blocks agree well with the computational results.The effective neutron multiplication coefficients in the MATR subcritical assembly with VV?R fuel elements were measured for different water levels. The range of determination of the effective multiplication coefficients was 0.7?0.97. The measured effective neutron multiplication coefficients agree with the results obtained using the shooting-source method.

Isothermal vapor−liquid equilibrium data for the system methanol + water + ammonium bromide at four salt molalities {(0.500, 1.000, 2.000, and 4.000) mol·kg^-1} have been measured with the help of headspace gas chromatography at (298.15 and 313.15) K. The experimental data were correlated using the electrolyte nonrandom two-liquid model and the extended universal quasichemical model.

A new series of CB1 ligands with high binding affinity (Ki = 0.7−100 nM) and moderate lipophilicity (cLogD7.4) in the range of 2.1−4.5 has been synthesized. A structure−activity relationship study demonstrated that for the studied set of aminoalkylindoles, the molecular dipole of the ground state conformation within the series was inversely related to the affinity. The racemic ligand with highest affinity (0.7 nM), 3-(4-fluoronaphthoyl)-1-(N-methylpiperidin-2-ylmethyl)indole, was radiolabeled with ¹⁸F. This radioligand specifically labeled CB1 receptors in mouse brain and accumulated in regions of high versus low CB1 receptor density in a ratio of 1.6. The displaceable radioactivity of one enantiomer in the brains of mice determined in a pretreatment study using the CB1 antagonist N-(piperidinyl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716) was nearly double that of the racemate for the same determination; therefore, the active enantiomer is a candidate for PET studies in animals. A pretreatement study for the other enantiomer found no displaceable radioactivity in the same group of mice; this result suggested the enantiomer was inactive.

Tellurite glasses were synthesized on the basis of the binary system composed of 70 mol % TeO2and 30 mol % ZnCl2and doped with Nd3+, Pr3+, Tb3+, Er3+, Yb3+, Ho3+. The physicochemical, luminescent, and magneto-optic properties of these glasses were studied.

Potential positron emission tomography (PET) ligands with low picomolar affinity at the nicotinic acetylcholine receptor (nAChR) and with lipophilicity (log D) ranging from −1.6 to +1.5 have been synthesized. Most members of the series, which are derivatives of 5-substituted-6-halogeno-A-85380, exhibited a higher binding affinity at α4β2-nAChRs than epibatidine. An analysis, by molecular modeling, revealed an important role of the orientation of the additional heterocyclic ring on the binding affinity of the ligands with nAChRs. The existing nicotinic pharmacophore models do not accommodate this finding. Two compounds of the series, 6-[¹⁸F]fluoro-5-(pyridin-3-yl)-A-85380 ([¹⁸F]31) and 6-chloro-3-((2-(S)-azetidinyl)methoxy)-5-(2-[¹⁸F]fluoropyridin-5-yl)pyridine) ([¹⁸F]35), were radiolabeled with ¹⁸F. Comparison of PET data for [¹⁸F]31 and 2-[¹⁸F]FA shows the influence of lipophilicity on the binding potential. Our recent PET studies with [¹⁸F]35 demonstrated that its binding potential values in Rhesus monkey brain were ca. 2.5 times those of 2-[¹⁸F]FA. Therefore, [¹⁸F]35 and several other members of the series, when radiolabeled, will be suitable for quantitative imaging of extrathalamic nAChRs.

Dogs were trained to tonic elevation of the forepaw and to use a lever to lift and maintain in position a food-containing cup during eating, this being accompanied by inclination of the head towards the feeder. In the conditions used here, the pretraining situation was that dogs would elevate the paw with an anticipatory upward movement of the lowered head; when the head tilted to the feeder, the paw flexed. The effect of special training, in which the initial coordination of the head and paw movements were remodeled, was that the animals maintained the paw elevated with the head in the lowered position. Dogs trained to perform the operant response with one paw did not transfer the acquired reaction when the “working” paw was changed. After the first training, the initial coordination was changed only between movements of the head and the “working” limb, but not between head movements and the non-trained paw. Remodeling of the initial movement coordination of the head with the second paw also occurred only as a result of the learning process.

The possibility that hindlimb movements (elevations) evoked by stimulation of the corresponding contralateral area of the motor cortex could be instrumentalized by reinforcement with food was demonstrated, contradicting some previously published data. Operant movements (interstimulus voluntary high elevations of the hindlimb) were acquired as a result of consistent combinations: cortical stimulation – movement – food. Acquisition required more than 50–200 combinations. Delivery of food was accompanied by a click at exactly the moment at which the hindlimb reached the required height. The click became the food-related conditioned signal and served as a secondary operant reinforcement, which facilitated acquisition of the operant movement. These results support the view that the motor cortex can have an immediate role in forming “operant” temporary connections (motivation-movement) and that simple operant movements can be initiated via this arc.

Exploration of the central CB1 cannabinoid receptors using positron emission tomography (PET) will allow for an understanding of the pharmacological and physiological role played by these receptors in the CNS. Current tracers are highly lipophilic compounds that exhibit very high nonspecific to specific binding ratios and as a result are inapt for use in humans. We have synthesized a series of less lipophilic analogues of SR141716 to serve as potential radioligands. Binding affinities of the series and a functional electrophysiological assay of three of our compounds have been presented.

Changes in the functional state of the sensorimotor cortex associated with reorganization of the natural pattern of postural rearrangement before limb elevation (the “diagonal” pattern and of an artificial rearrangement (the “unilateral” pattern) were studied in dogs. The state of cortical structures on postural rearrangement was assessed in terms of the pattern of somatosensory evoked potentials produced in response to stimulation of the forelimb during postural preparation of the animal for elevating the hindlimb (acquired avoidance response to a sound signal). Evoked potentials during the natural postural preparation (the “diagonal” pattern) were compared with those during the altered pattern of postural preparation (the “unilateral” pattern), this preparation taking place prior to elevation of the limb. Controls consisted of evoked potentials in the resting state. Decreases were seen in the latencies and amplitudes of most components of evoked potentials during postural rearrangement. In general, changes in evoked potentials were less marked in the “unilateral” pattern than in the “diagonal” pattern, though the differences were significant only for the amplitude of the first negative component. Changes in evoked potentials were similar regardless of whether the supporting forces of the limb to which the test stimulus was applied increased or decreased during postural rearrangement. It is suggested that differences in evoked potentials may reflect changes in the interaction between neuronal populations within the sensorimotor cortex during reorganization of the pattern of postural rearrangement associated with learning.

Reportedly, 2-[¹⁸F]fluoro-A-85380, 1, a promising radiotracer for imaging the nicotinic acetylcholine receptor (nAChR) by positron emission tomography (PET) in humans, exhibits slow penetration through the blood−brain barrier (BBB) due to its low lipophilicity. A ligand for nAChRs with greater lipophilicity than that of 1 would be potentially more favorable for PET imaging of nAChR due to its faster penetration through the BBB. Herein, a novel series of compounds has been developed based on the high affinity ligand for nAChRs, 2-chloro-5-((1-methyl-2-(S)-pyrrolidinyl)methoxy)-3-(2-(4-pyridinyl)vinyl)pyridine, 3b. The in vitro binding affinities for the new series were found to be in the range of Ki = 9−331 pM. A molecular modeling study showed differences in the comformational profiles and the electronic properties of these compounds, which provides further insight into the structure−activity relationships at nAChR. Lipophilicities of the compounds 3b−6b have been found to be substantially higher than that of 1. As a result, compounds 3b−6b might exhibit a faster penetration through the BBB than the less lipophilic 1. The N-methyl derivatives 3b and 6b demonstrated very high affinities at nAChRs (Ki = 28 and 23 pM, respectively) and will be targets for development of ¹¹CH3-labeled derivatives as radiotracers for PET imaging of nAChRs.

Abstract??Using the integral transformation method involving the investigation of the Laplace transforms of wave functions, we find the discrete spectra of the radial Schr?dinger equation with a confining power-growth potential and with the generalized nuclear Coulomb attracting potential. The problem is reduced to solving a system of linear algebraic equations approximately. We give the results of calculating the discrete spectra of the S-states for the Schr?dinger equation with a linearly growing confining potential and the nuclear Yukawa potential.

A gene of human tumor-associated antigen VNTR(MUC1) bound to streptavidin, an expression plasmid, and a highly effective hybrid protein-producing strain were constructed. It was shown that the streptavidin leader peptide ensures effective secretion of the hybrid protein into the periplasmic space ofEscherichia colicells. The hybrid protein was isolated in a homogeneous state and its immunogenic properties were studied.

Abstract: The evolution of a charged particle spin in electromagnetic fields of a special form is investigated based on the Bargmann-Michel-Telegdi equation. For some types of nonhomogeneous fields, an exact analytic form of the dependence of the spin vector on the four-dimensional velocity of the particle is found.

This paper discusses the induced radiation of electrons in the field of a plane electromagnetic wave propagating along the intensity vector of a uniform magnetic field. Expressions are obtained for the power and frequencies of the radiation. The role of the polarization of the plane wave in the radiation process and the effect of the magnetic field present on the induced radiation in the field of a plane wave are investigated. Several specific cases are discussed.

In this article, we study the scattering of free electrons and neutrons of an arbitrary force center having a charge and magnetic moment, taking into account the electric and magnetic anomalous moments of the Fermi particle. Polarization effects of scattering are also considered.

A study is made on a polarized neutron undergoing ß-decay induced by an intense electromagnetic wave. The angular distribution of electrons in the decay is obtained and their polarization is studied. A comparison is made with the decay of a moving neutron.

Within the framework of single-particle theory for Dirac particles, quasiclassical equations of spin motion in a magnetic field are obtained. Various operators are considered for the description of the spin properties of the particles moving in the external field. As a specific example, the equations for the magnetic moment in a focusing field are solved. The resonance character of these equations is noted.

The motion and radiation of an electron moving in the field of a plane wave of elliptical polarization and a magnetic field is considered. By the methods of classical and quantum theory, the effect of the plane-wave polarization on the characteristics of the particle motion and radiation is investigated. Some particular cases are considered.

The motion and radiation of electrons in a homogeneous magnetic field and the field of two plane waves propagating along the vector of the magnetic field intensity are considered. The law of motion and expressions for the total power, frequencies, and angular spectral distribution of the electron radiation intensity are obtained. An analysis is carried out of the results obtained in the case of small intensities of the plane waves. It is shown that the presence of the plane waves has a considerable effect on the characteristics of synchroton radiation.

In this work we study the leptonic-decay processes of a p-meson in a field that is a superposition of a crossed field and the field of a plane electromagnetic wave. Expressions for the decay probability are obtained that take into account a non-zero neutrino mass. The dependence of the probabilities on the spin of the created lepton is investigated. The values of the parameters of the external field are indicated for which it is possible to isolate the decay process depending on the neutrino mass, which may be of interest for the solution of the problem of the existence of the neutrino mass.

The pattern of change produced in somatosensory evoked potential (EP) in the forelimb projection area within the motor cortex (MI) following lesion of the projection area of the same limb in the somatosensory cortex (SI) or in parietal cortex area 5 was investigated during chronic experiments on waking dogs. Amplitude of the initial positive — negative wave of EP declined to 28–63% of preoperational level in all cases. No significant recovery of EP was noted for three weeks. Thus, a correlation between change in EP and spontaneous recuperation of the precision motor response occurring within two weeks after lesion of the SI did not exist. Nor was EP reinstated in the MI after ablation of area 5, despite complete but gradual reinstatement of EP (after an initial decline to 53%) in the nearby SI region. This protracted depression of EP seems to have been associated with breakdown of somatotopic sensory input from the SI or from area 5 to the MI, since EP in the motor cortex of the intact hemisphere and the hindlimb projection area within the MI on the lesioned side either remained unchanged or recovered within a week or two.

Analysis of domestic and foreign patent and scientific-technical literature has shown the fundamental possibility of using a biochemical method to clean up exhaust discharges from viscose manufacturing from such toxic sulfur-containing compounds as hydrogen sulfide and carbon disulfide.

Abstract: A model of instrumental conditioning similar to the classical model (Pavlovian) is proposed. Flexion of the ipsilateral forelimb was elicited while EDS was applied to the hind limb by stimulation of the motor area of the cortex (M1); both stimuli ceased during the raising of the forelimb. Uniform combinations of this kind led to the development of forepaw flexion reactions in response to the EDS of the hind paw. Prolongation of EDS by 3 sec following cortical stimulation led to rapid extinction of the developed reactions. Thus, the possibility of the effective instrumentalization of movements induced by stimulation of the M1 is proven. This argues that the forming “instrumental” connection (drive-motor structures) is addressed directly to the M1.

Conclusions 1.Isolated injury of the premotor and parietal regions of the associative cortex does not cause disturbances in a developed motor coordination associated with holding a raised forepaw with the head lowered; however, holding becomes less stable.2.Successive injury of the parietal and premotor regions, as does destruction of the sensorimotor cortex, leads to a breakdown of the developed coordination.3.The obtained results indicated that the parietal and premotor regions may be involved in the organization of new motor programs, which are realized by way of the sensorimotor cortex.

This paper discuses the t?p, t?p?t decay process in a field formed by the super-position of two fields: a crossed constant field and and electromagnetic plane-wave field. An expression is derived for the decay probability under the assumption of a nonzero t-neutrino mass. The dependence of the decay probability on the lepton spin and on the external-field parameters is analyzed. The variation of the decay probability with the neutrino mass and lepton spin yields information which may be useful for ascertaining the neutrino mass.

On the basis of general expressions obtained for the total emission probability and the probability of a radiation transition with spin reversal of an electron moving in an arbitrary plane-wave electromagnetic field, the particular case of a plane-wave field is considered. It is shown that under certain conditions self-polarization of the electron spin is possible during the emission by an electron in a field which is the superposition of a constant crossed field and a plane, elliptically polarized, electromagnetic wave.

The induced radiation of electrons moving in a plane, monochromatic, circularly polarized wave leads to a predominant orientation of the electron spin. Under certain conditions an electron beam can become completely polarized.