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Interaction of phonons with Dirac-like electronic states sets the fundamental limit of electron transport in topological insulators (TIs). Polarization-resolved and resonant Raman scattering of bulk and surface electronic excitation and vibrational modes in Bi 2 Te 3 and Bi 2- x Sb x Te 3- y Se y (BSTS) thin films was investigated. At photon energies ( E p ) of 1.57 and 2.54 eV, A11g and A21g (LO) modes in Bi 2 Te 3 and BSTS were resonantly excited owing to interband optical excitations of the surface Dirac state (DS) and bulk conduction band (CB), respectively. At room temperature, the resonance of the surface phonon of Raman and IR active modes E1u (LO) and A11u (LO) was observed in Bi 2 Te 3 because of interband excitation of bulk CB, and interband transition of DS resonantly excited the A21u (LO) surface phonon in BSTS. A Fano line-shape suggested interference in the presence of electron-phonon coupling of the surface states.

At the end of 36 years after the Chernobyl disaster, about 5 million people still live in the radioactively contaminated territories of Russia, Ukraine, and Belarus, and the density of radioactive contamination by Cesium-137 and Strontium-90 will remain radiologically significant for decades. We assessed cervical and endometrial cancer primary incidence (new cases) in the female population from the Bryansk region living in conditions of chemical, radioactive, and combined environmental contamination for 2000−2020. We found a significant increase in the long-term trend in the primary incidence of cervical and endometrial cancer in all the studied groups, regardless of the environmental conditions of residence (p < 0.00001). We did not find statistically significant differences in the incidence of cervical and endometrial cancer in women, regardless of the level of chemical, radioactive, and combined environmental contamination. However, women living in environmentally unfavorable areas (in total, in the territories of chemical, radioactive, and combined contamination) are statistically significantly more likely to develop endometrial cancer in terms of relative risk compared to environmentally safe (control) areas (RR 1.17 (1.08−1.27)). No such pattern was found for cervix cancer. It should be noted, since environmentally safe (control) areas have a certain level of contamination (albeit low), RR is underestimated.

The aim of the study was to investigate morphological traits of hepatic parenchymal tissue repair in response to injury using the conventional technique (closure) and an innovation method (such as hemostatic medication swab packing and modified batching). The experimental study was carried out on laboratory rats of the Winzar breed using light microscopy, standard stains for micropreparations, and morphometry. Histopathologic examination of micropreparations stained by standard methods revealed pronounced dystrophic processes in hepatocytes located near the necrotic zone (albuminous and hydropic degeneration and chromatin fragmentation in the nuclei). Morphometric studies showed a significant decrease (p<0.001) in almost all indicators of the size of cells and nuclei both near necrosis and distant from it on day 28 of the experiment in the experimental group in comparison to the control group. The results obtained pointed to more intense repair processes when applying the innovation method.

Background: Radioactive contamination and chemical pollution of the environment can affect the processes of carcinogenesis, including the formation of malignant neoplasms of the ovaries in women. We used the data of official state statistics for 2000-2020 to test the hypothesis about the effect of radioactive contamination (following the Chernobyl disaster) and chemical pollutants on the incidence of ovarian malignancies in the female population of the Bryansk region. Methods: A variety of statistical approaches were used to estimate the incidence of ovarian malignancies, including the Shapiro-Wilk test, Mann-Whitney U test, Spearman's rank correlation test and linear regression. Results: We did not establish statistically significant differences in the frequency of primary morbidity of women with malignant neoplasms of the ovaries, regardless of the environmental conditions of living. Furthermore, no significant correlations were found between the frequency of primary morbidity of ovarian malignancies, both with the level of contamination by Cesium-137 and Strontium-90, and air pollution with volatile organic compounds, carbon monoxide, sulfur dioxide and nitrogen oxides. A statistically significant increase in the long-term trend in the frequency of ovarian malignant neoplasms was revealed in the areas of chemical pollution ( p = 0.02), however, in other territories, no statistically significant regularities were established. The forecast of the frequency of newly diagnosed malignant neoplasms of the ovaries on average in the Bryansk region shows an increase of 12.4% in 2020 in comparison with the real data for 2020, while the largest increase in predicted values is recorded in the territories of radioactive contamination (by 79.6%), and the least in the combined territories (by 6.9%). Conclusions: The results obtained indicate the need for further work to understand the trends in the presence/absence of independent and combined effects of pollutants and the growth of oncogynecological pathology from the perspective of assessing the distant and regional metastasis, histological and immunohistochemical profile of a specific malignant ovarian neoplasm with levels of environmental contamination.

Background: Ionizing radiation and chemical pollution can disrupt normal embryonic development and lead to congenital malformations and fetal death. We used official government statistical data for 2000-2017 to test the hypothesis that radioactive and chemical pollutants influenced the frequency of de novo congenital malformations in newborns of the Bryansk region of southwest Russia., Methods: A variety of statistical approaches were used to assess congenital malformation frequencies including the Shapiro-Wilk test, White's homoscedasticity test, Wilcoxon T-test, Spearman's rank correlation test, and the inversely proportional regression., Results: We found that the frequency of polydactyly, multiple congenital malformations, and the frequency of de novo congenital malformations in newborns were significantly higher (p = 0.001-0.054) in regions with elevated radioactive, chemical and combined contamination. Polydactyly, multiple congenital malformations, and the sum of all congenital malformations were 4.7-7.4 times, 2.5-6.8 times, and 3.5-4.6 times higher in contaminated regions in comparison with the control group. The combination of both radioactive and chemical pollutants led to significantly higher frequencies of multiple congenital malformations when compared to regions with only one pollutant (radiation alone: 2.2 times, p = 0.034; chemical pollutants alone: 1.9 times, p = 0.008) implying that the effects of these stressors were at minimum additive. Although there was a trend for decreasing frequencies of multiple congenital malformations during the 2000-2017 period in areas of combined pollution, the opposite was true for regions with radioactive or chemical pollutants alone. However, overall, our models suggest that the frequency of multiple congenital malformations in areas of combined pollution will significantly (p = 0.027) exceed the frequencies observed for regions containing radioactive or chemical pollutants alone by 39.6% and 45.7% respectively, by 2018-2023., Conclusion: These findings suggest additive and potentially synergistic effects of radioactive and chemical pollutants on the frequencies of multiple congenital malformations in the Bryansk region of southwestern Russia., (© 2020 The Author(s).)

Trace amounts of water dissolved in minerals affect density, viscosity and melting behaviour of the Earth's mantle and play an important role in global tectonics, magmatism and volatile cycle. Water concentrations and the ratios of hydrogen isotopes in the mantle give insight into these processes, as well as into the origin of terrestrial water. Here we show the presence of molecular H 2 in minerals (omphacites) from eclogites from the Kaapvaal and Siberian cratons. These omphacites contain both high amounts of H 2 (70 to 460 wt. ppm) and OH. Furthermore, their ∂D values increase with dehydration, suggesting a positive H isotope fractionation factor between minerals and H 2 -bearing fluid, contrary to what is expected in case of isotopic exchange between minerals and H 2 O-fluids. The possibility of incorporation of large quantities of H as H 2 in nominally anhydrous minerals implies that the storage capacity of H in the mantle may have been underestimated, and sheds new light on H isotope variations in mantle magmas and minerals.

On the basis of official statistics of 1995-2014 a comparative analysis of the dynamics of stillbirths of boys and girls in the Bryansk region and the Russian Federation was carried out. The study established exceeding of rate of stillbirths in boys over stillbirths in girls at 14.4% and 9.0% correspondingly both in the Bryansk Oblast and the Russian Federation that confirms the global trend of higher risk of stillbirth in boys by approximately to 10%. In case the stillbirth rate in the Bryansk Oblast will proceed established trend the ratio of stillbirths will increase relatively to the nationwide values in 2016 - 2021 and will reach 30% in 2021. At that, the gap between indices of boys and girls will increase up to 32,8%.

A pressure shift of Raman band of liquid water (H 2 O) may be an important tool for measuring residual pressures in mineral inclusions, in situ barometry in high-pressure cells, and as an indicator of pressure-induced structural transitions in H 2 O. However, there was no consensus as to how the broad and asymmetric water Raman band should be quantitatively described, which has led to fundamental inconsistencies between reported data. In order to overcome this issue, we measured Raman spectra of H 2 O in situ up to 1.2 GPa using a diamond anvil cell, and use them to test different approaches proposed for the description of the water Raman band. We found that the most physically meaningful description of water Raman band is the decomposition into a linear background and three Gaussian components, associated with differently H-bonded H 2 O molecules. Two of these components demonstrate a pronounced anomaly in pressure shift near 0.4 GPa, supporting ideas of structural transition in H 2 O at this pressure. The most convenient approach for pressure calibration is the use of "a linear background + one Gaussian" decomposition (the pressure can be measured using the formula P (GPa) = -0.0317(3)·Δν G (cm -1 ), where Δν G represents the difference between the position of water Raman band, fitted as a single Gaussian, in measured spectrum and spectrum at ambient pressure).

The incommensurately modulated twin structure of nyerereite Na 1.64 K 0.36 Ca(CO 3 ) 2 has been first determined in the (3 + 1)-dimensional symmetry group Cmcm(α00)00s with modulation vector q = 0.383a*. Unit-cell values are a = 5.062 (1), b = 8.790 (1), c = 12.744 (1) Å. Three orthorhombic components are related by threefold rotation about [001]. Discontinuous crenel functions are used to describe the occupation modulation of Ca and some CO 3 groups. The strong displacive modulation of the O atoms in vertexes of such CO 3 groups is described using x-harmonics in crenel intervals. The Na, K atoms occupy mixed sites whose occupation modulation is described in two ways using either complementary harmonic functions or crenels. The nyerereite structure has been compared both with the commensurately modulated structure of K-free Na 2 Ca(CO 3 ) 2 and with the widely known incommensurately modulated structure of γ-Na 2 CO 3 .

On the basis of official statistical data for 1999-2014 the authors assessed the frequency of polydactyly, reduction defects of limbs and multiple congenital malformations in newborns of the Bryansk region living in the areas with different densities of radioactive contamination by long-lived radionuclides cesium-137.(3.0 to 2523.4 kBq/m(2)) and strontium-90 (from 0.02 to 42.5 kBq/M(2)). The findings did not reveal statistically significant differences in the frequency of polydactyly, reduction defects of limbs and multiple congenital malformations in newborns in the South-Western Territories compared with medium-regional values, although the maximum value of the sum of congenital. developmental anomalies (polydactyly, reduction limb defects and multiple congenital malformations) are detected in the above-mentioned most contaminated areas.

On the basis of official statistics for 1999-2014 there was performed the comparative evaluation of the prevalence of congenital malformations de novo: polydactyly, reduction limb defects and multiple congenital malformations in newborns of radiation-contaminated areas of the Bryansk area residing in areas with the various density of radioactive contamination by long lived radionuclides cesium-137 (from 10.0 to 2523.4 kBq/m) and strontium-90 (from 0.7 to 42.5 kBq/m). The findings showed no statistically significant differences in the prevalence of polydactyly, reduction limb defects and multiple congenital malformations in newborns in the South-Western areas compared to medium regional values, although the maximum value of the amount of congenital malformations de novo is found in most radiation-contaminated areas.

The use of the buccal mucosa cell micronucleus test for comparison of chemical, radiation, and radiation-chemical environmental pollution has been considered. The combined impact of chemical and radiation factors has been found to cause additive effects, synergism, and inhibition. It has been noted that the cytogenetic characteristics of the buccal epithelium may be used as a "biological dosimeter" of the total level of environmental pollution.

Comparative evaluation of the frequency of incidence of all forms of primary malignant tumors in the child population over the fourteen-year period (1995-2008.) is presented. Evaluation was carried out in ecologically unfavorable territories of the Bryansk region with varying density of radioactive (from 28.1 to 661.9 kBq/m2 for 137Cs), toxic (from 1.47 to 183.6 kg/person/year for gaseous toxic substances) and combined environment pollution. Statistically significant differences of incidence of malignant neoplasms in children in ecologically unfavorable areas have been established.

Confocal Raman imaging of fluid inclusions in garnet porphyroblasts from diamond-grade metamorphic calc-silicate rocks from the Kumdy-Kol microdiamond deposit (Kokchetav Massif, Northern Kazakhstan) reveals that these fluid inclusions consist of almost pure water with different step-daughter phases (e.g., calcite, mica and rare quartz). These fluid inclusions are characterized by negative crystal shape of the host-garnet and they exclusively occur within the core of garnet porphyroblasts. These observations are consistent with their primary origin, most likely at ultrahigh-pressure (UHP) metamorphic conditions. The euhedral newly formed garnet, different in color and composition, was found to be associated with these fluid inclusions. It is proposed that newly formed garnet and water fluid inclusions appear by reaction between the hydrous fluid and the garnet-host. These fluid inclusions provide an unequivocal record of almost pure H(2)O fluids, indicating water-saturated conditions within subducted continental crust during prograde stage and/or ultrahigh-P metamorphism., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The presence of aragonite inclusions in garnet from diamond-grade metamorphic rocks from the Kokchetav Massif, Northern Kazakhstan was identified for the first time by means of Raman analyses and mapping. Aragonite appears within the inclusions up to 50 μm in size as a single crystal. These inclusions have rounded shape. The grain boundary between the host-garnet is smooth. No cracks occur around the aragonite inclusions. No significant shift in the main aragonite Raman band was measured. These observations indicate that residual pressure within the inclusion is minor. These findings imply either non-UHPM origin of the host garnet or significant plastic deformation of host minerals during retrograde stage. These features should be taken into account for recovery peak metamorphic conditions and modeling of exhumation processes of UHPM complexes., (Copyright © 2010 Elsevier B.V. All rights reserved.)

We have performed petrographic and spectroscopic studies of brown diamonds from an eclogite xenolith from the Udachnaya pipe (Yakutia, Russia). Brown diamonds are randomly intermixed with colorless ones in the rock and often located at the grain boundaries of clinopyroxene and garnet. Brown diamonds can be characterized by a set of defects (H4, N2D and a line at 490.7 nm) which are absent in colorless diamonds. This set of defects is typical for plastically deformed diamonds and indicates that diamonds were likely annealed for a relatively short period after deformation had occurred. Excitation of brown colored zones with a 632.8 nm He-Ne laser produced the typical diamond band plus two additional bands at 1730 cm(-1) and 3350 cm(-1). These spectral features are not genuine Raman bands, and can be attributed to photoluminescence at ∼710 nm (1.75 eV) and ∼802 nm (1.54 eV). No Raman peak corresponding to graphite was observed in regions of brown coloration. Comparison with previous reports of brown diamonds from eclogites showed our eclogitic sample to have a typical structure without signs of apparent deformation. Two mechanisms with regard to diamond deformation are proposed: deformation of eclogite by external forces followed by subsequent recrystallization of silicates or, alternatively, deformation by local stress arising due to decompression and expansion of silicates during ascent of the xenolith to surface conditions., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Raman-based geobarometry has recently become increasingly popular because it is an elegant way to obtain information on peak metamorphic conditions or the entire pressure-temperature-time (P-T-t) path of metamorphic rocks, especially those formed under ultrahigh-pressure (UHP) conditions. However, several problems need to be solved to get reliable estimates of metamorphic conditions. In this paper we present some examples of difficulties which can arise during the Raman spectroscopy study of solid inclusions from ultrahigh-pressure metamorphic rocks.

For the first time burkeite was observed as a daughter phase in the melt inclusions in olivine by Raman spectroscopy. The olivine comes from sheared lherzolite xenoliths from the Udachnaya-East kimberlite pipe (Yakutia, Russia). This anhydrous sulfate-carbonate mineral (Na(6)(CO(3))(SO(4))(2)) is generally considered to be a characteristic mineral in saline soils or in continental lacustrine evaporite deposits. Recently, however, this mineral was identified in hydrothermal fluids. Our observations indicate that burkeite can also be formed from a mantle-derived melt.

Coesite inclusions occur in a wide range of lithologies and coesite is therefore a powerful ultrahigh-pressure (UHP) indicator. The transformation of coesite to quartz is evidenced by three optically well identifiable characteristics (e.g. palisade textures, radial crack patterns, polycrystalline quartz pseudomorphs). Under overpressure monomineralic coesite (on an optical basis), lacking the above transformation characteristics may survive. Raman micro-spectroscopy was applied on monomineralic coesite inclusions in garnet porphyroblasts from diamond-bearing garnet-clinozoisite-biotite gneisses of the Barchi-Kol area (Kokchetav Massif, Northern Kazakhstan). These coesite inclusions are euhedral and display a characteristic anisotropic hallo. However, Raman maps and separate spectra of these inclusions display shifted bands for coesite and quartz. Microscopically undetectable, quartz shows on the Raman map as a thin shell around coesite inclusion. Shift of the main coesite band allows to estimate their overpressure: coesite inclusions record 0-2.4 GPa in garnet and zircon. The quartz shell remains under lower pressure 0-1.6 GPa. The possible application of coesite and quartz Raman geobarometers for UHP metamorphic rocks is discussed.

Metamorphic diamond is a powerful but frequently debated indicator for ultrahigh-pressure metamorphic (UHPM) conditions. Because of their small size, their optical identification needs confirmation. Characteristics of chemically extracted microdiamonds from Kokchetav, identified by different analytical methods, are used here for unambiguous in situ identification by Raman microspectroscopy. Differences appear in the diamond spectra and the Raman analytical method is explored as a helpful tool in the discrimination between diamond populations from four different UHPM lithologies of Kokchetav. Not considering the graphite-coated diamond, out of the reach of the laser wavelength used here, the comparison of these Kokchetav Raman spectra may provide additional information in other UHPM studies.