Conodonts of the Krevyakinian and Khamovnikian Substages of the Kasimovian Stage in the Type Region (Moscow Basin)

2019 ◽  
Vol 53 (9) ◽  
pp. 950-955
Author(s):  
N. V. Goreva ◽  
A. S. Alekseev
Keyword(s):  
Type Region ◽  
Kasimovian Stage ◽  
Moscow Basin

Biostratigraphical analysis of the Moscovian–Kasimovian transition at the neostratotype of Kasimovian Stage (Afanasievo section, Moscow Basin, Russia)

Palaeoworld ◽  
2009 ◽  
Vol 18 (2-3) ◽  
pp. 102-113 ◽  
Author(s):  
Natalia Goreva ◽  
Alexander Alekseev ◽  
Tatiana Isakova ◽  
Olga Kossovaya
Keyword(s):  
Kasimovian Stage ◽  
Moscow Basin

The issue of radioactive contamination in context of ecosystem services development

2016 ◽  
Vol 3 (3) ◽  
pp. 48-53 ◽  
Author(s):  
G. Chobotko ◽  
L. Raychuk ◽  
I. McDonald
Keyword(s):  
Ecosystem Services ◽  
The State ◽  
Natural Ecosystems ◽  
Type Region ◽  
State Register ◽  
Agrarian Policy ◽  
Literary Sources ◽  
Radiation Contamination ◽  
Logical Research

The aim of the article was to defi ne the role of the radioactive environment contamination in the formation of ecosystem services strategy. Methods. Monographic, systemic and structural, factor analysis, abstract and logical research methods have been used. The data from the State Statistics Service of Ukraine, the Ministry of Agrarian Policy and Food of Ukraine, the Ministry of Ecology and Natural Resources of Ukraine, materials of scientifi c researches, international materials and reports and other literary sources on the issues investigated have been used as an information base. Results. Retrospective analysis of sources and state of radioactive eco- systems contamination was conducted and the priority steps in developing the concept of ecosystem services in conditions of radiation contamination were found. Conclusions. The current socio-ecological paradigm of the transition from environmental use to environmental management should be refl ected in the relevant envi- ronmental management mechanisms. Currently, when assessing the state of ecosystem services in Ukraine and worldwide one must take into account the changes in food demand of residents of radioactively contaminated areas, the exploitation of radioactively safe ecosystems growth, their overload and degradation. All of this re- quires an inventory of ecosystem services by type, region, consumers, etc. and the formation of a state register of ecosystem services with a clear assignment of area of responsibility for appropriate natural ecosystems. This will help to make the economic evaluation of different ecosystem services and mechanisms of charges for ecosystem services.

scholarly journals Biology and Physics of Heterochromatin-Like Domains/Complexes

Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1881
Author(s):  
Prim B. Singh ◽  
Stepan N. Belyakin ◽  
Petr P. Laktionov
Keyword(s):  
Phase Separation ◽  
Fission Yeast ◽  
Thermodynamic Description ◽  
Dynamic Structure ◽  
Vertebrate Development ◽  
Type Region ◽  
Additional Tool ◽  
3D Genome ◽  
Chromatin Template ◽  
Cis And Trans

The hallmarks of constitutive heterochromatin, HP1 and H3K9me2/3, assemble heterochromatin-like domains/complexes outside canonical constitutively heterochromatic territories where they regulate chromatin template-dependent processes. Domains are more than 100 kb in size; complexes less than 100 kb. They are present in the genomes of organisms ranging from fission yeast to human, with an expansion in size and number in mammals. Some of the likely functions of domains/complexes include silencing of the donor mating type region in fission yeast, preservation of DNA methylation at imprinted germline differentially methylated regions (gDMRs) and regulation of the phylotypic progression during vertebrate development. Far cis- and trans-contacts between micro-phase separated domains/complexes in mammalian nuclei contribute to the emergence of epigenetic compartmental domains (ECDs) detected in Hi-C maps. A thermodynamic description of micro-phase separation of heterochromatin-like domains/complexes may require a gestalt shift away from the monomer as the “unit of incompatibility” that determines the sign and magnitude of the Flory–Huggins parameter, χ. Instead, a more dynamic structure, the oligo-nucleosomal “clutch”, consisting of between 2 and 10 nucleosomes is both the long sought-after secondary structure of chromatin and its unit of incompatibility. Based on this assumption we present a simple theoretical framework that enables an estimation of χ for domains/complexes flanked by euchromatin and thereby an indication of their tendency to phase separate. The degree of phase separation is specified by χN, where N is the number of “clutches” in a domain/complex. Our approach could provide an additional tool for understanding the biophysics of the 3D genome.

APPLICATION OF EPITAXIAL UNIPOLAR BARRIERS TO REDUCE NOISE CURRENTS IN PHOTODETECTORS

2011 ◽  
Vol 20 (03) ◽  
pp. 557-564
Author(s):  
G. R. SAVICH ◽  
J. R. PEDRAZZANI ◽  
S. MAIMON ◽  
G. W. WICKS
Keyword(s):  
Leakage Current ◽  
Surface Passivation ◽  
Leakage Currents ◽  
Type Region ◽  
Surface Leakage Current ◽  
Unipolar Barrier ◽  
Trap Assisted Tunneling ◽  
Assisted Tunneling ◽  
Tunneling Currents ◽  
Surface Leakage

Tunneling currents and surface leakage currents are both contributors to the overall dark current which limits many semiconductor devices. Surface leakage current is generally controlled by applying a post-epitaxial passivation layer; however, surface passivation is often expensive and ineffective. Band-to-band and trap assisted tunneling currents cannot be controlled through surface passivants, thus an alternative means of control is necessary. Unipolar barriers, when appropriately applied to standard electronic device structures, can reduce the effects of both surface leakage and tunneling currents more easily and cost effectively than other methods, including surface passivation. Unipolar barriers are applied to the p -type region of a conventional, MBE grown, InAs based pn junction structures resulting in a reduction of surface leakage current. Placing the unipolar barrier in the n -type region of the device, has the added benefit of reducing trap assisted tunneling current as well as surface leakage currents. Conventional, InAs pn junctions are shown to exhibit surface leakage current while unipolar barrier photodiodes show no detectable surface currents.

Tectono-sedimentary model for the evolution of the Silves Group (Triassic, Lusitanian basin, Portugal)

2012 ◽  
Vol 183 (3) ◽  
pp. 203-216 ◽  
Author(s):  
António Ferreira Soares ◽  
José Carlos Kullberg ◽  
Júlio Fonseca Marques ◽  
Rogério Bordalo da Rocha ◽  
Pedro Miguel Callapez
Keyword(s):  
Field Work ◽  
Coarse Grained ◽  
Variscan Orogeny ◽  
Type Region ◽  
The North ◽  
Detailed Structural Analysis ◽  
Sequential Organization ◽  
Eastern Border ◽  
Tensional Stress ◽  
Lusitanian Basin

Abstract At the beginning of the Alpine cycle, the breakup of Pangea lead to the early stages of the North Atlantic opening. In the western Iberian sector of the European margin, the Lusitanian basin starts to evolve bordered eastwards by inherited reliefs from the late episodes of the Variscan orogeny. The base unit, the Silves Group, considered not earlier than the Carnian, is mainly siliciclastic and predominantly formed by arcosarenites to feldspar litarenites, coarse to very coarse-grained (wackes) and pebbly, where the sediment architecture denotes organizations in continental (Conraria, Penela and Castelo Viegas Formations) environments. A first marine episode (Isocyprina Beds of Pereiros Fm.) marks a significant change within the sedimentary record; the uppermost part corresponds to intertidal transitional environments (sabkha). New and detailed field work of sedimentological and structural nature that has been carried out in recent exposures from the type-region of Coimbra-Penela enabled us to make significant observations and to improve data collection. This allowed a full reinterpretation of the paleotectonic and paleogeographical conditions under which the Silves Group and, consequently, the eastern border of the Lusitanian basin, evolved. This study carried out in the type-region also allowed a better understanding of its sequential organization. All units are unconformity bounded by strong influxes of coarse siliciclastics from the Iberian meseta. One of those unconformities (D2b) is an angular unconformity with cartographic expression. Tectonic reconstructions were possible to make after a detailed structural analysis of normal synsedimentary faults. Regional comparisons with Eastern Iberian basins that evolved since Permian times are also discussed. We conclude that the lower red siliciclastic units are older than has been considered until now. Those units were formed in a previous tensional stress pattern of tardi-Variscan affinities, related to megashear dextral kinematics of Permian-Triassic age. We propose that units below D2b unconformity can record a Proto-Lusitanian basin; the Lusitanian basin is younger and evolved mainly after the Triassic-Jurassic limit (Castelo Viegas Fm.) within an E-W extensional context related to Atlantic type basins.

Carboniferous conodont biostratigraphy of the Dianzishang section, Zhenning, Guizhou, South China

2013 ◽  
Vol 151 (2) ◽  
pp. 311-327 ◽  
Author(s):  
YUPING QI ◽  
KEYI HU ◽  
QIULAI WANG ◽  
WEI LIN
Keyword(s):  
South China ◽  
North American ◽  
Primitive Form ◽  
Conodont Biostratigraphy ◽  
The World ◽  
Kasimovian Stage ◽  
Moscovian Stage ◽  
Stage Boundaries ◽  
Serpukhovian Stage ◽  
Bashkirian Stage

AbstractA preliminary summary of the lower Visean to uppermost Moscovian (Carboniferous) conodont succession and biostratigraphy of the Dianzishang section in Zhenning, Guizhou, South China is presented. Eleven conodont zones, in ascending order, can be recognized:Gnathodus praebilineatus,Gnathodus bilineatus,Lochriea ziegleri,Declinognathodus noduliferus,Neognathodus symmetricus, ‘Streptognathodus’expansus(primitive form), ‘Streptognathodus’expansus,Mesogondolella donbassica – Mesogondolella clarki,Idiognathodus podolskensis,Swadelinafauna andIdiognathodus swadeizones. The first occurrences ofLochriea ziegleriat the base of the Serpukhovian Stage,Declinognathodus noduliferus noduliferusat the base of the Bashkirian Stage and ‘Streptognathodus’expansusat the base of the Moscovian Stage are recognized. The definitions of these stage boundaries, as well as that of the base of the Kasimovian Stage are discussed. Correlations with the Naqing section in South China, Russian and North American sections, as well as other important sections in the world, are considered.

Stratigraphic correlation of the Permian-Triassic red beds constrained by detrital zircon geochronology: Moscow basin, East European platform

2021 ◽  
Author(s):  
Alvina Chistyakova ◽  
Roman Veselovskiy
Keyword(s):  
Detrital Zircon ◽  
East European Platform ◽  
Lower Triassic ◽  
Detrital Zircons ◽  
Upper Permian ◽  
Stratigraphic Correlation ◽  
Red Beds ◽  
East European ◽  
Moscow Basin ◽  
Stratigraphic Position

<p>There's no doubt that nowadays detrital zircon U-Pb geochronology is actually required method of sedimentary basins analysis. Furthermore, this approach may have a lot of applications, such as a stratigraphic correlation. Here we present the first results of U–Pb LA–ICP–MS dating of detrital zircon from the Permian-Triassic red beds located within the Moscow Basin of the East European platform. Two outcrops have been studied: the Zhukov Ravine P/T boundary reference section and the Nedubrovo strata with uncertain stratigraphic position (uppermost Permian or lower Triassic?).</p><p>U–Pb ages of detrital zircon grains have been obtained for two samples – the Upper Permian and Lower Triassic age, which were taken in the proximity to the Permian–Triassic boundary in the Zhukov Ravine. Corresponding age distributions show contrasting provenance of the studied sedimentary rocks, pointing out that principal change in source of clastic material occurred on the Paleozoic-Mesozoic boundary. It means that detrital zircon U–Pb geochronology can be used as an additional independent tool for stratigraphic correlation of the Permian-Triassic red beds, at least within the Moscow Basin. We demonstrate this in the case of the Nedubrovo section with debated (Permian or Triassic?) stratigraphic position: the obtained data on detrital zircons persuasively suggests Early Triassic age of the Nedubrovo strata.</p><p>This study is supported by the Russian Foundation for Basic Research (project no. 18-05-00593).</p>

scholarly journals BPF-type region-of-interest reconstruction for parallel translational computed tomography

2017 ◽  
Vol 25 (3) ◽  
pp. 487-504 ◽  
Author(s):  
Weiwen Wu ◽  
Hengyong Yu ◽  
Shaoyu Wang ◽  
Fenglin Liu
Keyword(s):  
Computed Tomography ◽  
Region Of Interest ◽  
Type Region
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