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Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.Vasilieva Liudmila E Savinetskaya Andrey V.Tchabovsky A.N.Severtsov institute of Ecology and Evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

Cross-method Analysis of Corotation Radii Data Set for Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 98-113页

作者： V.S.Kostiuk A.A.Marchuk A.S.Gusev Sternberg Astronomical institute Lomonosov Moscow State University Central (Pulkovo) Astronomical Observatory Russian Academy of Sciences Saint Petersburg State University

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structure Ωp, and therefore understand its nature. In the literature, there are plenty of methods to estimate this value, but do these measurements have any consistency? In this work, we collected a data set of corotation radius measurements for 547 galaxies, 300 of which had at least two values. An initial analysis reveals that most objects have rather inconsistent corotation radius positions. Moreover, a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of measurements. These findings do not have any relation to spiral type, Hubble classification, or presence of a bar. Among other reasons, obtained results could be explained by the transient nature of spirals in a considerable part of galaxies. We have made our collected data sample publicly available, and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies: fundamental parameters galaxies: kinematics and dynamics galaxies: structure

Life Origin in the Milky Way Galaxy: III. Spatial Distribution of Overheated Stars in the Solar Neighborhood

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 693-709页

作者： Alexander N. Safronov Obukhov institute of Atmospheric Physics Russian Academy of Sciences Moscow Russia

A concept of ensemble averaged stellar reactors is developed to study the dynamics of processes occurring in stars, allocated in the ~200 pc solar neighborhood. According to the effective temperature value, four stellar classes are identified, for which the correlation coefficients and standard deviation are counted. The theory of the buoyancy terrestial elements is generalized to stellar systems. It was suggested that stars are over-heated due to the shift parameters of the nuclear processes occurring inside the stars, which leads to the synthesis of transuranium elements until the achievement of a critical nuclear mass and star explosion. The heavy transuranium elements sink downward and are concentrated in the stellar depth layers. The physical explanation of the existence of the critical Chandrasekhar star limit has been offered. Based on the spatial analysis of overheated stars, it was suggested that the withdrawal of the stellar reactor from the equilibrium state is a consequence of extragalactic compression inside the galaxy arm due to the arm spirality (not to be confused with the spirality of the galaxy itself).

关键词： Stellar Nucleogenesis Ensemble-Averaged Stellar Reactor Overheated Stars Chandrasekhar Stellar Limit Arm Spirality

Life Origin in the Milky Way Galaxy: I. The Stellar Nucleogenesis of Elements Necessary for the Life Origin

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 647-680页

作者： Alexander N. Safronov Obukhov institute of Atmospheric Physics Russian Academy of Sciences Moscow Russia

Chemical elements in space can be synthesized by stellar nuclear reactors. Studying the dynamics of processes occurring in the stars introduces a concept of the ensemble-averaged stellar reactor. For future interstellar missions, the terrestrial and solar abundances were compared with considerable number of stars allocated in the ~200 pc solar neighborhood. According to the value of the effective temperature, four stellar classes are distinguished, for which the correlation coefficients and standard deviation are calculated. The statement about the possibility of transferring heavy elements synthesized by stars over long distances in space has been completely refuted. There is no immutability of the distribution of elements on neighboring stars and in the Solar System. It is shown that chemical elements are mainly synthesized inside each stellar reactor. The theory of the buoyancy of elements is generalized to stars. It has been suggested that stars overheat due to a shift in the parameters of nuclear processes occurring inside stars, which leads to the synthesis of heavy elements.

关键词： Stellar Nucleogenesis Solar Abundance Ensemble-Averaged Stellar Reactor Stellar Abundance Interstellar Mission Habitability DNA-Star

Assessment of the Design Displacement Values at Seismic Fault Crossings and of Their Excess Probability

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Journal of Mountain Science 2011年第2期8卷 228-233页

作者： STROM Alexander IVASCHENKO Alexey KOZHURIN Andrey institute of geospheres dynamics of russian academy of sciences institute of Oceanology of russian academy of sciences Geological institute of russian academy of sciences

Line structures such as pipelines that cross active faults should be designed to retain leak-tightness if the design displacement (Ddesign) occurs. Principal approaches to the Ddesign and rupture kinematics assessment are described. They are based on relationships between earthquake magnitude, rupture length and displacement, and on the detailed field data on a specific fault that crosses the pipeline route. Since the future offset at the crossing may exceed the design value, the probability of a displacement occurrence where the safety of the structure can not be ensured should be estimated. Assessment method on such event probability is described and exemplified through active fault studies carried out at several pipeline projects in Russia.

关键词： Active Fault Surface Rupture Design Displacement Pipeline Sakhalin Island

Constitutive Laws of the Underground Opening Collapse due to Dynamic Load

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Transactions of Tianjin University 2008年第B10期14卷 483-490页

作者： Alexander BUDKOV Gevorg KOCHARYAN institute for dynamics of geospheres Russian Academy of Sciences Moscow Russia

The constitutive laws of the collapse of underground openings in a rock massif were in-vestigated based on the results of laboratory and field experiments, and computations using ana-lytical and numerical models. It is shown that the principal mechanism of failure of underground openings over important for practice peak particle velocity amplitude range of 1 to 10 m/s is the roof and wall breakage due to the fall of key blocks. Over this load range the material crushing is of considerably less importance. The geometry of discontinuities influences mainly the stability of key blocks. Further caving depends weakly on block structure of near-tunnel zone. The mean volume of fall material is a rather stable quantity for rock massifs of different structures. Lower tunnel sta-bility in the zones of high fracturing is caused by a higher probability of the presence of the unsta-ble key blocks and the decrease of strength characteristics of fractured bounding blocks. The de-crease of average block size is a less important accompanying factor.

关键词： explosion underground opening rock discontinuity key block dynamic load

Multivariate statistical and bioinformatic analyses for the seasonal variations of actinobacterial community structures in a drinking water reservoir

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Journal of Environmental sciences 2024年第3期137卷 1-17页

作者： Haihan Zhang Sixuan Pan BenMa Tinglin Huang Dmitry B.Kosolapov Manli Ma Xiang Liu Huan Liu Xiaoyan Liu Shaanxi Key Laboratory of Environmental Engineering Key Laboratory of Northwest Water ResourceEnvironment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Papanin institute for Biology of Inland Waters of russian academy of sciences(IBIW RAS) 109BorokNekouzYaroslavl152742Russia

Actinobacterial community is a conspicuous part of aquatic ecosystems and displays an important role in the case of biogeochemical cycle,but little is known about the seasonal variation of actinobacterial community in reservoir ecological *** this study,the high-throughput techniques were used to investigate the structure of the aquatic actinobacterial community and its inducing water quality parameters in different *** results showed that the highest diversity and abundance of actinobacterial community occurred in winter,with Sporichthya(45.42%)being the most abundant genus and Rhodococcus sp.(29.32%)being the most abundant *** analysis and correlation analysis suggested that in autumn the dynamics of actinobacterial community were infuenced by more factors and Nocardioides ***2R5S2 was the potential keystone species which was negatively correlated with temperature(R=-0.72,Pdynamics of temperature,dissolved oxygen(DO),and turbidity are potential conspicuous factors infuencing seasonal actinobacterial community *** partial least squares path modeling further elucidated that the combined effects of DO and temperature not only in the diversity of actinobacterial community but also in other water qualities,while the physiochemical parameters(path coefficient=1.571,Pdynamics and structures of actinobacterial community in the drinking water reservoirs and provide scientific guidance for further water quality management and protection in water sources.

关键词： Source water reservoir High-throughput sequencing Correlation analysis Network analysis Partial least squares path modeling

Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova Sergey V.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology institute for Metals Superplasticity Problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University institute of Mechanical Science Problems of RAS institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations Voids Boundary conditions

Potential triggers for large earthquakes in open-pit mines:A case study from Kuzbass,Siberia

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Deep Underground Science and Engineering 2022年第2期1卷 101-115页

作者： Gevorg Kocharyan Chengzhi Qi Svetlana Kishkina Vladimir Kulikov Sadovsky institute for dynamics of geospheres of russian academy of sciences MoscowRussia Civil and Transportation School Beijing University of Civil Engineering and ArchitectureBeijingChina

The extraction and movement of rock during mining operations is considered a possible trigger for slip along the *** this study,possible anthropogenic causes were analyzed for triggering the earthquake with the local magnitude ofML=6.1(at a depth of 4km just beneath the quarry),in the vicinity of the large coal open-pit mine in *** event was the largest earthquake associated with a quarry(an open pit).A sufficiently deep occurrence of the source testified that seismic vibrations were produced in a dynamic slip along a preexisting and prestressed tectonic *** calculations were conducted of increments of normal and shear stresses at fault planes with several dip angles at depths corresponding to the probable location of the hypocenter of the Bachat *** the results show,long-term rock excavations bring a prestressed thrust fault closer to the ultimate Coulomb strength,and stress variations at those depths may suffice to initiate a movement along the *** measuring seismic vibrations at different quarries and mines in Russia,the dynamic effect at the supposed depth of the source occurrence could be reliably *** is shown,the ultimate anticipated dynamic deformations are noticeably lower than corresponding values produced by seismic waves of distant earthquakes in the case when the effects of dynamic triggering were ***,the seismic effect of explosions cannot trigger a large earthquake with deep source *** in open-pit mines can only bring forward the moment of an earthquake at a potentially seismogenic *** the same time,the numerical calculations reveal that a branching network of underground tunnels located at several horizons can noticeably reduce the effective shear modulus of the host *** effect can even provoke a dynamic movement at a previously aseismic fault.

关键词： anthropogenic impact Coulomb stress variations fault induced seismicity mine seismicity open pits