A microtomographic study of the internal structure of sulfide minerals from the ore-bearing rock varieties of two economically significant deposits in the Arctic zone of the Russian Federation, ...disseminated ore of the Pilgujarvi Cu–Ni deposit (Pechenga) and metalliferous gabbronorites of the platinum-bearing Fedorovo–Pansky complex (Kola Peninsula), was carried out. It was shown that all sulfide samples studied had a homogeneous structure without obvious defects or silicate inclusions larger than 1 µm. The absence of silicate microinclusions larger than one micron in sulfides testifies to the isomorphism of rare earth element (REE) occurrence in sulfides and eliminates, to a certain extent, the debatable problem of the influence of microinclusions on the results of Sm–Nd isotope-geochronological studies of sulfides. The presence of smaller (10–500 nm) silicate microinclusions is, with a high degree of probability, unable to control the total REE budget in a sulfide mineral. The conclusion of the absence of a significant effect of microinclusions on the obtained ages is confirmed by the results of Sm–Nd dating using sulfides from the same mineral aliquots: the Sm–Nd ages of the ores of the Pilgujarvi Cu–Ni deposit were estimated at 1965 ± 87 Ma; and the ore-bearing gabbronorites of the Fedorovo-Pansky complex, at 2482 ± 61 Ma. This agrees well with the datings obtained earlier using other isotopic systems (U–Pb, Re–Os).
Results of isotope-geochronological Sm-Nd studies of the Paleoproterozoic platiniferous Fedorovo-Pansky layered intrusive are presented. Implementation of a complex of isotope-geochemical methods ...(Sm-Nd, U-Pb, Rb-Sr) allowed a more reliable and precise study of the age, formation patterns, and conditions of ore substance localization in the major units of the complex, i.e., the Fedorova Tundra and Kievey deposits. Geological, mineralogical, and isotope-geochronological data combined facilitate the identification of three ore-magmatic systems within the Fedorovo-Pansky ore area: 1) early troctolite-gabbronorite (2526-2507 Ma); 2) major ore-bearing norite-gabbronorite-anorthosite (2502-2470 Ma); 3) anorthosite (2447 Ma). The main industrial PGE mineralization of the Fedorovo-Pansky ore area is related to the norite-gabbronorite-anorthosite ore-magmatic system with the age of 2500-2470 Ma. Analysis of Sm-Nd model ages for the Fedorova Tundra (2.9 - 3.4 Ma) and West-Pana (2.8 - 3.1 Ma) blocks of the complex indicated that the age range for the Fedorova Tundra intrusive chamber is inclined to more ancient ages, which is confirmed by geological observations of individual intrusive chambers of the complex blocks.
The effect of thermodynamic nonequilibrium of hydrogen isotope recycling, which consists in significant deviation of the velocity distribution function (VDF) of neutral hydrogen isotope atoms from ...the Maxwellian VDF, on the passive signal of the charge-exchange recombination spectroscopy (CXRS diagnostics) of edge plasma in tokamaks is analyzed using the ITER tokamak reactor as an example. The calculations of the VDF for atomic and molecular deuterium are carried out using the three-dimensional Monte Carlo code EIRENE as a part of the two-dimensional transport code SOLPS and the semi-analytical Ballistic Model BM1D2V, which is one-dimensional in coordinate and two-dimensional in projections of atomic velocity. The source of level population of the Be IV beryllium ion, the line radiation of which is used in the CXRS diagnostics, is calculated for the above two methods of calculating the VDF and the average atomic kinetic energy, as well as in the case of neglecting the thermodynamic nonequilibrium of recycling, when the temperature of atoms is equal to the temperature of the plasma ions. The calculations of the cross section for the charge-exchange reaction of beryllium ions Be V on deuterium atoms using the ARSENY code and other codes and the erosion kinetics of the beryllium first wall using the three-dimensional code ERO2.0 are used. The calculations of the level populations of the Be IV beryllium ion using the
nl
-KinRyd code, the luminosity of the ions, and the passive charge-exchange radiation intensity on the observation chord are carried out for the three indicated cases of the VDF of deuterium atoms. A significant dependence of the results of the conducted predictive modeling on the thermodynamic nonequilibrium of recycling is shown.
Ring chromosome 18 is a rare chromosomal disorders that usually originate de novo and correlate with clinical manifestation: developmental delay as well as microcephaly, brain and ocular ...malformations, hypotonia and skeletal abnormalities. We generate iPSC clonal cell line ICGi024-A with pluripotency properties which were demonstrated in vitro by three germ layer differentiation capacity. ICGi024-A can be used for disease modeling and fundamental investigation of ring chromosome instability.
The first Sm/Nd and
40
Ar/
39
Ar isotope–geochronological studies of amphibolite of the Khanmeikhoi Formation of the Kharbei metamorphic complex (Kharbei Block, Polar Urals) showed that metamorphism ...reaching the conditions of the amphibolite facies of moderate and high pressures occurred in the Devonian (367 ± 40 Ma (amphibole, plagioclase, whole rock), 392 ± 23 Ma (amphibole, garnet, whole rock), Sm/Nd method) and is consistent with the age estimates of high-pressure and regressive metamorphism within the Marunkeu Block. They correspond to the stage of radical restructuring of subduction processes that began in the Silurian to the east of the Baltica, associated with the subduction of the paleocontinent edge beneath the island arc and wedging of the subduction zone. The regressive stage and the beginning of the exhumation of the Kharbei metamorphic complex occurred in the Early Carboniferous (346 ± 5 Ma, amphibole,
40
Ar/
39
Ar method). Judging from the model age of amphibolite (Т(DM2) of 1.07 and 1.13 Ga) corresponding to the Middle–Late Riphean boundary, the Khanmeikhoi Formation is not older than that time.
Ring chromosomes are structural aberrations commonly associated with disease phenotype. We consider necessary to create the iPSCs with a ring chromosome 8, which can be used for disease modeling and ...related research. The ICGi025-A iPSCs line was obtained by the reprogramming of the skin fibroblasts from a 1-year-old boy with 46,XY,r(8)/45,XY,–8 mosaicism, developmental delay, microcephaly, dysmorphic features, diffuse muscle hypotonia, moderate proximal muscle weakness, feeding problems, and motor alalia. The iPSCs had expression of the pluripotency-associated markers. In vitro differentiated cells expressed the markers of the cells of three germ layers. That data allowed us to conclude that ICGi025-A cells were pluripotent.
Expansion over 200 CGG repeats in FMR1 gene causes inherited intellectual disability or autism spectrum disorder named as fragile X syndrome. Despite the known cause fragile X syndrome pathogenesis ...has not been specified yet. The ICGi026-A iPSCs line was obtained by the reprogramming of the peripheral blood mononuclear cells from a 9-year-old boy with fragile X syndrome. The ICGi026-A iPSCs expressed pluripotency markers, had a normal male karyotype (46, XY) and had the capacity to in vivo differentiate into the cells of three germ layers.
The U-Pb dating zircon and Sm-Nd dating the whole rock and secondary minerals from the Kanozero massif of alkaline granites of the Kola region (the Fennoscandian shield) have been carried out. The ...age of alkaline granites of the Kanozero massif by zircon is 2667 ± 36 Ma, aplite-like alkaline granites - 2301 ± 13 Ma and blastomylonites - 2264 ± 12 Ma. The crystallization temperature of zircon has been estimated from the crystal habit. According to the zircon morphology of alkaline granites and blastomylonites the conditions during the crystallization process of the Kanozero massif have been established as long-term cooling high-temperature volatile- and alkali-rich crustal-mantle melts. The mineral Sm-Nd isochron by whole rock and by secondary minerals - biotite and titanite - has an age of 1921 ± 53 Ma interpreted as the time of regional Svecofene metamorphism. Based on the obtained isotopic data it can be noted that the rocks of the Kanozero massif of alkaline granites have similar features of formation and transformation with alkaline granites of the Keivsky terrane.
Results are provided for an experimental study of the effect of deoxidation on the composition of nonmetallic inclusions in pipe steels melted in a vacuum induction furnace with a periclase lining. ...Thermodynamic calculations are made for oxygen activity within melts with lanthanum, cerium, aluminum, and yttrium for the metal of four melts. Conditions are evaluated for magnesium spinel inclusion formation in relation to deoxidant used and the extent of deoxidation. The effect is demonstrated of reduced aluminum concentration during metal ladle treatment on nonmetallic inclusion composition and the possibility of modifying them in the course of an industrial pipe steel melt.
In the study of materials on electron probe devices in the field of action of the electron beam, a contaminating hydrocarbon film is formed, which affects the experimental results. In this paper, we ...have studied the influence of a contamination film on carbon-film-coated dielectrics on the intensity of cathodoluminescence and characteristic X-ray lines. The absorption coefficient of the contamination film in the visible and UV ranges has been determined. Filming mechanisms at different parameters of the electron beam have been discussed.
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