The chemical and isotopic compositions of glass fragments found on the site of a former 18th – 19th glass plant in Kazan are studied. The finds are divided into three basic groups in terms of three ...types of glass from which they are fabricated: Ca–K, Ca–K–Na, and Ca–Na–K. The data on the chemical and isotopic composition show difference between the glasses in terms of recipe and raw material source. Comparison of the analytical and historical data suggested that each group of glasses corresponds to a definite time period of production. The composition of one group indicates the possibility that soda ash was added to the recipe.
The phase composition and spatial distribution of chemical components in the volume of coins of medieval Volga Bulgaria are studied using the neutron-diffraction- and neutron-tomography methods. Two ...coins belonging to different time periods of this medieval state are studied: a Samanid multidirham dating from the first half of the 10th Century and a silver dirham dating from the period of the reign of the Bulgarian emir Bulat-Timur. It is established that both coins consist of a copper-silver alloy. In the Samanid multidirham, the average volume contents of copper and silver are found to be about 50%. Minor spatial variations in the chemical composition are found in the volume of the multidirham under study. It is established that the volume average silver content in the Bulat-Timur dirham is about 95%.
The article introduces the main results of the scientific activity of the Institute of Archaeology named after A.Kh. Khalikov of the Tatarstan Academy of Sciences in the year of its 5th anniversary. ...The Institute is a leading academic scientific institution in the field of archaeology in the Volga region. In 2019, excavations were performed at 16 archaeological heritage sites in the Republic of Tatarstan, the Volga region and other regions of the Russian Federation, as well as the Republic of Mongolia. The Institute has held 14 scientific conferences, workshops and schools, 11 international and 3 All-Russian events. The organization publishes two academic scientific journals. As a result of an analysis of publishing activity completed by SCImago, the scientific journal The Volga River Region Archaeology published by the Institute was included in the Q2 quartile. The second scientific journal of the Institute of Archaeology named after A.Kh. Khalikov “The Archaeology of the Eurasian Steppes” was included in the list of peer-reviewed publications of the Higher Attestation Commission of the Russian Federation in 2019. The recognition of the Museum of Archaeology of the Republic of Tatarstan as a safekeeper of the heritage of regional academic archaeological science reflected in the inclusion of the Museum of Archaeology of the Institute in the Register of Museums of the Russian Federation in March, 2019.
Long-length ultrafine-grained (UFG) Ti rods are produced by equal-channel angular pressing via the conform scheme (ECAP-C) at 200°C, which is followed by drawing at 200°C. The evolution of ...microstructure, macrotexture, and mechanical properties (yield strength, ultimate tensile strength, failure stress, uniform elongation, elongation to failure) of pure Ti during this thermo-mechanical processing is studied. Special attention is also paid to the effect of microstructure on the mechanical behavior of the material after macrolocalization of plastic flow. The number of ECAP-C passes varies in the range of 1–10. The microstructure is more refined with increasing number of ECAP-C passes. Formation of homogeneous microstructure with a grain/subgrain size of 200nm and its saturation after 6 ECAP-C passes are observed. Strength properties increase with increasing number of ECAP passes and saturate after 6 ECAP-C passes to a yield strength of 973MPa, an ultimate tensile strength of 1035MPa, and a true failure stress of 1400MPa (from 625, 750, and 1150MPa in the as-received condition). The true strain at failure failure decreases after ECAP-C processing. The reduction of area and true strain to failure values do not decrease after ECAP-C processing. The sample after 6 ECAP-C passes is subjected to drawing at 200¯C resulting in reduction of a grain/subgrain size to 150nm, formation of (101¯0) fiber texture with respect to the rod axis, and further increase of the yield strength up to 1190MPa, the ultimate tensile strength up to 1230MPa and the true failure stress up to 1600MPa. It is demonstrated that UFG CP Ti has low resistance to macrolocalization of plastic deformation and high resistance to crack formation after necking.
Ancient DNA analysis has revealed an involvement of the bacterial pathogen Yersinia pestis in several historical pandemics, including the second plague pandemic (Europe, mid-14th century Black Death ...until the mid-18th century AD). Here we present reconstructed Y. pestis genomes from plague victims of the Black Death and two subsequent historical outbreaks spanning Europe and its vicinity, namely Barcelona, Spain (1300–1420 cal AD), Bolgar City, Russia (1362–1400 AD), and Ellwangen, Germany (1485–1627 cal AD). Our results provide support for (1) a single entry of Y. pestis in Europe during the Black Death, (2) a wave of plague that traveled toward Asia to later become the source population for contemporary worldwide epidemics, and (3) the presence of an historical European plague focus involved in post-Black Death outbreaks that is now likely extinct.
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•Three historical Yersinia pestis genomes from the second plague pandemic in Europe•Low genetic diversity of the pathogen during the Black Death•Indication for link between the Black Death and 19th century plague pandemic lineages•Connection between post-Black Death outbreaks in Europe supports a local plague focus
Spyrou et al. have sequenced historical Yersinia pestis genomes from victims of the Black Death and subsequent outbreaks in Europe. Their data suggest a connection between the Black Death and the modern-day plague pandemic as well as the persistence of plague in Europe between the 14th and 18th centuries.
The effects of different dopamine concentrations on contractility of myocardium with blocked α- or β-adrenoceptors were examined
in vitro
in 21- and 100-day old rats. In myocardial strips with ...blocked α-adrenoceptors, dopamine (10
—5
M) increased the right atrial contractile force. By contrast, this neurotransmitter (10
—9
-10
—5
M) reduced the contractile force of atrial and ventricular strips with blocked β-adrenoceptors.
The article features the results of an research in a potential source of feedstock for Bolgar pottery production. The authors address the issues of history and techniques of studying certain aspects ...of Bolgar pottery. The article contains the results of the application of natural scientific and statistical methods in the field of identification of sampling areas and locations of feedstock for the production of unglazed ceramics. The chemical and mineralogical characteristics of feedstock and ceramic samples were used during identification. The investigation allows identify the sources of clay feedstock for the production of handicraft ceramics in Bolgar of the Golden Horde period. Of particular interest are the similarities with respect to ceramics from manufacturing complexes. A potential location of pottery feedstock extraction is the flood basin of the Melenka river (the aquatorium of Kuibyshev reservoir). The obtained results revealed considerable potential in the organization of investigations on the identification of feedstock sources. The authors outline the prospects of applying the proposed technique in the aspect of studying Bolgar pottery of the Golden Horde period.
Adrenal Gland Hormones in Primary School Children Shaikhelismanova, M. V.; Dikopol’skaya, N. B.; Sitdikov, F. G. ...
Bulletin of experimental biology and medicine,
04/2015, Letnik:
158, Številka:
6
Journal Article
Recenzirano
It was found that in 8-9-year-old children, the hormonal part of the sympathoadrenal system more rapidly develops in boys, while the transmitter part develops more rapidly in girls. The androgenic ...and glucocorticoid function of the adrenal cortex matures earlier in girls. To the end of the school year, excretion of epinephrine and norepinephrine decreased, which attests to the development of fatigue.
The structural characteristics and phase composition of several ancient brass ingots obtained in the archeological Shcherbet complex has been studied using neutron diffraction and tomography methods. ...The XRF analysis and neutron diffraction provide high zinc content up to 30 wt.%. The neutron tomog- raphy yielded 3D data of the spatial distribution of chemical elements in the brass alloy of the studied ingots, as well as inner voids and cavities as a possible result of the gas output during casting process. The patina, as a cuprite phase, occupy volumes to 8 % of the volumes of the ingots.
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