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In the Cis- and Trans-Baikal regions of the southern part of Eastern Siberia, the detailed study and dating of geoarchaeological deposits and the erosion channel network (gullies, floodplains, and river terraces), along with the interpretation of high-resolution satellite images, have revealed areas of modern cryogenic processes as well as horizons with cryoturbations from the second half of the Late Pleistocene and the Holocene (MIS 3–1). Modern cryogenic landforms are found in swampy areas on gentle slopes, floodplains, and river terraces and are mainly represented by cryogenic cracks, hummocks, and thaw sinks; in river beds they are represented by icings. This paper establishes the formation ages of cryogenic horizons and distinguishes the permafrost phenomena of MIS 3–1. The stages of cryogenesis are associated with cold events, permafrost aggradation, the activation of cryogenic processes, and ice wedge polygon relief formation. During interglacials and interstadials, climate warming lead to permafrost degradation, ice thawing, active layer growth, erosion, cryokarst (thermokarst) development, suffusion, the acceleration of slope processes, the infilling of cryogenic relief forms, erosion network changes, the activation of erosion-accumulative processes, and sedimentation in river valleys. The second half of the Late Pleistocene contains five stages of active cryogenesis (49–42 k, 38–32.5 k, 29–23 k, 21–14.5 k, 12.9–11.7 k cal. BP), 1 each of which can be further divided into shorter phases. For example, in the Nadeino section (Western Trans-Baikal), three layers are distinguished with cryoturbations dated ~14.5–14.4 k, ~12.7–12.5 k, and 11.9–11.7 k cal. BP. In the Nizhniaia Bulanka section, one cryogenic horizon (formed at ~12.8–11.8 k cal. BP) was identified. Cryogenic horizons are categorized as syngenetic or epigenetic depending on the formation process. Polygonal-block reliefs (hummocks) are clearly visible in high-resolution space images of river basins on floodplains, terraces, watersheds, and gentle slopes within arable lands. These hummocks range from 4 to 50 m wide and 0.5–3 m high, and are divided by swales and hollows. The paleocryogenic relief on the watersheds and slopes formed in Early MIS 2 (29–23 k cal. BP) and, subsequently, experienced several stages of aggradation and degradation, resulting in a hummocky-hollow relief with sporadic permafrost distribution. Degradation of the permafrost during Late Glacial (15–11 k BP) and Early Holocene warming caused the formation of thermokarst (cryokarst), sheet and gully erosion, suffusion, sedimentation in river valleys, and changes in the microrelief of the upper links of the erosion network. Existing dells, rills, and gullies are the modern manifestations of paleocryogenic depressions and troughs.

Gully erosion has important on and off site effects. Therefore, several studies have been conducted over the past decades to quantify gully headcut retreat (GHR) in different environments. Although these led to important site-specific and regional insights, the overall importance of this erosion process or the factors that control it at a global scale remain poorly understood. This study aims to bridge this gap by reviewing research on GHR and conducting a meta-analysis of measured GHR rates worldwide. Through an extensive literature review, GHR rates for 933 individual and actively retreating gullies have been compiled from more than 70 study areas worldwide (comprising a total measuring period of > 19 600 years). Each GHR rate was measured through repeated field surveys and/or analyses of aerial photographs over a period of at least one year (maximum: 97 years, median: 17 years). The data show a very large variability, both in terms of gully dimensions (cross-sectional areas ranging between 0.11 and 816 m 2 with a median of 4 m 2 ) and volumetric GHR rates (ranging between 0.002 and 47 430 m 3 year − 1 with a median of 2.2 m 3 year − 1 ). Linear GHR rates vary between 0.01 and 135 m year − 1 (median: 0.89 m year − 1 ), while areal GHR rates vary between 0.01 and 3628 m 2 year − 1 (median: 3.12 m 2 year − 1 ). An empirical relationship allows estimating volumetric retreat rates from areal retreat rates with acceptable uncertainties. By means of statistical analyses for a subset of 724 gullies with a known contributing area, we explored the factors most relevant in explaining the observed 7 orders of magnitudes of variation in volumetric GHR rates. Results show that measured GHR rates are significantly correlated to the runoff contributing area of the gully (r 2 = 0.15) and the rainy day normal (RDN; i.e. the long-term average annual rainfall depth divided by the average number of rainy days; r 2 = 0.47). Other factors (e.g. land use or soil type) showed no significant correlation with the observed GHR rates. This may be attributed to the uncertainties associated with accurately quantifying these factors. In addition, available time series data demonstrate that GHR rates are subject to very large year-to-year variations. As a result, average GHR rates measured over short ( 100%) uncertainties. We integrated our findings into a weighted regression model that simulates the volumetric retreat rate of a gully headcut as a function of upstream drainage area and RDN. When weighing each GHR observation proportional to its measuring period, this model explains 68% of the observed variance in GHR rates at a global scale. For 76% of the monitored gullies, the simulated GHR values deviate less than one order of magnitude from their corresponding observed value. Our model clearly indicates that GHR rates are very sensitive to rainfall intensity. Since these intensities are expected to increase in most areas as a result of climate change, our results suggest that gully erosion worldwide will become more intense and widespread in the following decades. Finally, we discuss research topics that will help to address these challenges.

First complexes of tetra(1,2,5-thiadiazolo)porphyrazine with representatives of rare earth elements [TSDPzM(acac)] (M = Y and Lu) were prepared by complexation of the metal free macrocycle [TSDPzH2] with YIII and LuIII acetylacetonates in o-dichlorobenzene in the presence of DBU. The obtained complexes were characterized by MALDI-TOF mass-spectrometry, IR spectroscopy and by electronic absorption and fluorescence emission spectra. The DFT calculations performed for the model complexes [TSDPzM(Cl)] evidence that coordination of Y and Lu leads to considerable doming deformation of the TSDPz macrocycle and were used for the assignment of the characteristic bands observed in the experimental IR spectra.

An assessment of the total soil loss from cultivated land was undertaken for the Chernozems–Kastanozems belt of European Russia and Siberia, based on the results of the National Soil Survey for administrative regions and the detailed study of three sentinel catchments, located in different parts of the Russian Plain. The soil profile truncation method was used to assemble data on soil erosion for the period of intensive agriculture, which ranged in duration between 110 and 230 years for the different parts of the sentinel study catchments and which had mean durations of 50–220 years for the total area of arable land comprising the administrative regions of Russia. The average value of the mean annual erosion rate for all regions of European Russia was estimated at 0.5 mm yr−1 for Chernozems and 0.4 mm yr−1 for Kastanozems, equivalent to ~6 t ha−1 yr−1 and ~4.8 t ha−1 yr−1, respectively. The total volume of soil eroded on arable lands during the period of ploughing, in the Chernozems–Kastanozems soil belt of Russia, amounted to 33.4 × 109 m3 (excluding sediment re-de-position on the arable land). The topography of arable slopes and the erosion index of precipitation are the critical factors determining the differences in the rates of soil loss, both at the level of small catchments and at regional level, while the duration of the ploughing period does not significantly affect the proportion of eroded land. The contribution of wind erosion to soil loss of the study regions located in the dry steppe zone is identified. It was established that the values of soil erosion rates obtained using the soil profile truncation method are in good agreement with the evaluation of soil erosion rates compiled during long-term monitoring of soil loss using runoff plots. Our rates of soil loss do not agree with recent estimates based on the revised universal soil loss equation (RUSLE) for some administrative regions of European Russia with significant wind erosion.

Inhalation exposure of outbred female white rats (initial age about 4 months) to formaldehyde vapours (12.8 ± 0.69 mg/m 3 ) 4 h per day, 5 days per week during 10 weeks induced statistically significant changes in some indices characterizing differential WBC count, functional status of the central nervous system and liver, redox and porphyrin metabolisms, bone marrow micronuclei count as well as free amino acid spectrum of the blood serum. The development of intoxication was accompanied by increased urinary excretion of formaldehyde, formic acid and methanol. Daily oral administration of glutamate (150–180 mg), glycine (12 mg) and methionine (50 mg) in combination rendered all of the formaldehyde's toxic effects reduced. This administration also caused a significant increase in the ratio between the rates of excretion of formic acid and non-metabolized formaldehyde. This shift supposedly reflects activation of oxidative detoxifying biotransformation of formaldehyde. Taking into consideration that the combination of amino acids used in this study proved innocuous in protectively effective doses, the administration in this combination may be recommended to humans exposed to high levels of formaldehyde in workplace or ambient air.

Introduction Targeted superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as a promising detection tool for the molecular magnetic resonance imaging (MRI). Decoration of the surface with specific moieties that have anti-tumour immunotherapeutic activity could provide a theranostic potential for the nanocomplexes. Combination of functionalized particles with blocking of immune checkpoint inhibitors could further enhance the therapeutic benefit. Material and methods Synthesised nanoparticles conjugated with granzyme B (GrB-SPIONs) were in vitro assessed (employing confocal and electron microscopies, flow cytometry) for specific targeting of the membrane-bound Hsp70 in cancer cells. Application of GrB-SPIONs as a monotherapy or in combination with single dose (10Gy) radiotherapy (SARRP, X-strahl) was performed in the orthotopic models of human U87 glioblastoma in NMRI nu/nu mice, GL261 glioma in C57/Bl6 mice, C6 glioma in rats. Combinatorial therapy of anti-CTLA-4 and anti-PD-1 anitbodies with GrB-SPIONs and radiotherapy was performed. Results and discussions Internalised GrB-SPIONs in Hsp70-positive tumour cells induced apoptotic death in dose- and time-dependent manner (as shown by flow cytometry). Monotherapy with GrB-SPIONs in animal models resulted in delayed tumour progression (MRI volumometry) and increased survival. Biodistribution analysis employing highly sensitive non-linear magnetic response measurements (NLR- M 2 ) confirmed the retention of particles in the tumour (that was further proved by histological studies). Addition of radiotherapy further promoted therapeutic benefit of systemically administered nanoparticles. Subsequent therapy with anti-CTLA-4 and anti-PD-1 antibodies synergistically improved the efficacy of GrB-SPIONs nanocomplexes with radiotherapy. Inhibitory immune checkpoint blockade significantly enhanced inflitration of tumour tissue with activated CD8 +and natural killer (NK1.1) cells and decreased suppressive PD-1 +cells. Conclusion These findings reveal that GrB-SPIONs can specifically target Hsp70-positive cancer cells that could be used simultaneously for nonivasive MRI diagnosis of tumours and therapy. Combinatorial regimen of targeted nanocomplexes and immune checkpoint inhibitors has a high theraputic potency that could be translated into clinial trials.

Introduction The stress-inducible 72 kDa heat shock protein (mHsp70) is known to be expressed on the plasma membrane of tumour cells, but not on the corresponding normal cells. Targeting of the mHsp70 might provide a promising strategy for theranostics. Functionalized superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as a promising contrast agents for the molecular magnetic resonance imagning (MRI). Coating of nanoparticles surface with therapeutic ligands could provide an anti-cancer activity. Material and methods Synthesised nanocomplexes were conjugated with anti-Hsp70 tools (including monoclonal cmHsp70.1 antibodies (cmHsp70.1-SPIONs), granzyme B (GrB-SPIONs), tumour penetrating peptide TPP (TPP-SPIONs)) and in vitro analysed for specific targeting of mHsp70 in cancer cells. Diagnostic potential of nanoparticles for MRI was assessed in the orthotopic models of U87 glioblastoma in NMRI nu/nu mice, C6 glioma in rats, orthotopic H1339 lung cancer in immunodeficient nu/nu mice, GL261 glioma in C57/Bl6 mice. To increase the tumour accumulation of particles additionally an external magnetic field was applied. Theranostic potential of GrB-SPIONs (that have a pro-apoptotic activity) was assessed as a monotherapy or in combination with radiotherapy. Results and discussions Superparamagentic conjugates had a high contrast enhancing properties (NMR relaxivity studies) and specifically targeted Hsp70-positive tumour cells (as shown by confocal and electron microscopies, flow cytometry) in a dose-dependent manner. High-resolution MRI (11 T) on T2-weighted images demonstrated the retention of conjugates in the tumour site. Biodistribution analysis employing highly sensitive non-linear magnetic response measurements (NLR- M 2 ) confirmed the retention of particles in the tumour (that was further confirmed by histological studies). Application of the external magnetic field further enhanced accumulation of the nanocarriers in the tumour. Due to the pro-apoptotic potency of GrB-SPIONs conjugates the latter, when being systemically administered in tumor-bearing animals, not only targeted the Hsp70-positive tumours but also induced the delay of cancer progression (MRI volumometry) and increased the survival. Combination of GrB-SPIONs with radiotherapy further enhanced the anti-cancer activity of the conjugates. Conclusion Overall, the data showed that Hsp70-targeted superparamagnetic nanoparticles have a potential to be used for the early detection and therapy of the tumours.

The mean values of potential soil loss and of sediments that are removed from the gullies are calculated, and the data on the rates of erosion-accumulative processes on arable lands, in gully-dried-up river-bed systems are provided. For the Yelovka and Kuitunka rivers the basin component of the erosion-accumulative processes has been assessed qualitatively. The sequences of erosion loss to drainage basins of small rivers as well as of scouring and accumulation are determined.

We investigate the structure of the dilatation operator D of planar N = 4 SYM in the sector of single trace operators built out of two chiral combinations of the 6 scalars. Previous results at low orders in 't Hooft coupling λ suggest that D has a form of an SU ( 2 ) spin chain Hamiltonian with long range multiple spin interactions. Instead of the usual perturbative expansion in powers of λ, we split D into parts D ( n ) according to the number n of independent pairwise interactions between spins at different sites. We determine the coefficients of spin–spin interaction terms in D ( 1 ) by imposing the condition of regularity of the BMN-type scaling limit. For long spin chains, these coefficients turn out to be expressible in terms of hypergeometric functions of λ, which have regular expansions at both small and large values of λ. This suggest that anomalous dimensions of “long” operators in the two-scalar sector should generically scale as λ at large λ, i.e., in the same way as energies of semiclassical states in dual AdS 5 × S 5 string theory.

By considering AdS_5 x S^5 string states with large angular momenta in S^5 one is able to provide non-trivial quantitative checks of the AdS/CFT duality. A string rotating in S^5 with two angular momenta J_1,J_2 is dual to an operator in N=4 SYM theory whose conformal dimension can be computed by diagonalizing a (generalization of) spin 1/2 Heisenberg chain Hamiltonian. It was recently argued and verified to lowest order in a large J=J_1+J_2 expansion, that the Heisenberg chain can be described using a non-relativistic low energy effective 2-d action for a unit vector field n_i which exactly matches the corresponding large J limit of the classical AdS_5 x S^5 string action. In this paper we show that this agreement extends to the next order and develop a systematic procedure to compute higher orders in such large angular momentum expansion. This involves several non-trivial steps. On the string side, we need to choose a special gauge with a non-diagonal world-sheet metric which insures that the angular momentum is uniformly distributed along the string, as indeed is the case on the spin chain side. We need also to implement an order by order redefinition of the field n_i to get an action linear in the time derivative. On the spin chain side, it turns out to be crucial to include the effects of integrating out short wave-length modes. In this way we gain a better understanding of how (a subsector of) the string sigma model emerges from the dual gauge theory, allowing us to demonstrate the duality beyond comparing particular examples of states with large J., 49 pages. v2,v3: misprints and coefficients in eqs.(2.77),(2.89) corrected; comments about quadratic terms in the effective action added at the end of section 2.3 and section 3

We analyse the collective spontaneous emission from a thin solid film comprised of three-level atoms with a Λ -configuration of operating transitions. The thickness of the system is assumed to be smaller than the emission wavelength so that the local-field correction to the acting field appears to be of importance and affects significantly the three-level super-radiance. Because of this correction, there exists a competition between the operating transitions, resulting, under suitable conditions, in the complete suppression of one of them.

This report describes the impact-parameter trigger used by the WA92 BEATRICE fixed-target experiment at the CERN Omega spectrometer. A comprehensive description of the microstrip detector, readout electronics and trigger processor is given. Preliminary results on its operation in the 1992 data collection are also presented.