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Integrative Zoology 2022年第5期17卷 849-878页

作者： alexander n.kuznetsov Borissiak Paleontological Institute Russian Academy of SciencesMoscowRussia

Comparative study of terrestrial locomotion of 4ﬁsh genera including Anabas,Channa,Clarias,and Monopterus,was performed in experimental setting with the substrate surface of wet clay.no special adaptations for terrestrial locomotion were found.Everyﬁsh uses for propulsion on land what it already has.Eel-shaped Monopterus crawls by body undulations in a serpentine or sidewinding technique,the latter of which was not previously observed beyond snakes.The other 3ﬁsh genera walk by body oscillations using stiff appendages as propulsors.When they are located anteriorly,as the serrate operculum in Anabas and the preaxial spine of the pectoralﬁn in Clarias,the propulsion is termed prolocomotor,when posteriorly,as the spiny analﬁn in Channa—metalocomotor.Channa is the heaviestﬁsh walking out of water in our days,quite comparable in size withﬁrst Devonian tetrapods Acan-thostega and Tulerpeton.A theoretical calculation is suggested for the upper size limit of aﬁsh capable of terrestrial walking without special locomotor adaptations.It should be roughly 20 cm in the vertical dimension of the trunk,which is just a little above the known size of Devonian tetrapodomorphﬁshes Panderichthys and Elpistostege.The metalocomotor walking technique of Channa is suggested as the closest extant model for terrestrial locomotion at theﬁsh-tetrapod transition.The major difference is that the metalocomotor propulsor in Channa is represented by the analﬁn,while in tetrapodomorphs by the pelvicﬁns.The sprawled pelvicﬁns were advantageous in respect of reduced requirement for side-to-side tail swinging.

关键词： ﬁsh-tetrapod transition metalocomotor propulsion prolocomotor propulsion snakehead

A blind climber:The first evidence of ultrasonic echolocation in arboreal mammals

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Integrative Zoology 2017年第2期12卷 172-184页

作者： Aleksandra A.PAnYUTInA alexander n.kuznetsov Ilya A.VOLODIn Alexei V.ABRAMOV Irina B.SOLDATOVA Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Vertebrate Zoology Faculty of BiologyLomonosov Moscow State UniversityMoscowRussia Scientific Research Department Moscow ZooMoscowRussia Zoological Institute Russian Academy of SciencesSaint PetersburgRussia Joint Vietnam-Russian Tropical Research and Technological Centre HanoiVietnam

The means of orientation is studied in the Vietnamese pygmy dormouse Typhlomys chapensis,a poorly known enigmatic semi-fossorial semi-arboreal rodent.Data on eye structure are presented,which prove that Typhlomys(translated as“the blind mouse”)is incapable of object vision:the retina is folded and retains no more than 2500 ganglion cells in the focal plane,and the optic nerve is subject to gliosis.Hence,Typhlomys has no other means for rapid long-range orientation among tree branches other than echolocation.Ultrasonic vocalization recordings at the frequency range of 50-100 kHz support this hypothesis.The vocalizations are represented by bouts of up to 7 more or less evenly-spaced and uniform frequency-modulated sweep-like pulses in rapid succession.Structurally,these sweeps are similar to frequency-modulated ultrasonic echolocation calls of some bat species,but they are too faint to be revealed with a common bat detector.When recording video simultaneously with the ultrasonic audio,a significantly greater pulse rate during locomotion compared to that of resting animals has been demonstrated.Our findings of locomotion-associated ultrasonic vocalization in a fast-climbing but weakly-sighted small mammal ecotype add support to the“echolocation-first theory”of pre-flight origin of echolocation in bats.

关键词： arboreal locomotion reduced eyes Rodentia Typhlomys ultrasonic echolocation

Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： Aleksey S.Ilintsev Elena n.nakvasina alexander P.Bogdanov northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

Interstitial Doping of SnO_(2) Film with Li for Indium-Free Transparent Conductor

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Chinese Physics Letters 2024年第3期41卷 140-145页

作者：陈兴谦李昊臻陈伟梅增霞 alexander Azarov Andrej kuznetsov 杜小龙 Beijing national Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Department of Physics Centre for Materials Science and NanotechnologyUniversity of OsloP.O.Box 1048BlindernN-0316 OsloNorway Guangdong SinoPrime Technology Co. Ltd.Dongguan 523808China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

SnO_(2)films exhibit significant potential as cost-effective and high electron mobility substitutes for In_(2)O_(3)films.In this study,Li is incorporated into the interstitial site of the SnO_(2)lattice resulting in an exceptionally low resistivity of 2.028×10^(-3)Ω·cm along with a high carrier concentration of 1.398×10^(20)cm^(-3)and carrier mobility of 22.02 cm^(2)/V·s.

关键词： exceptional resistivity substitute

A Converse Theorem for Split SO_(2l) over Finite Fields

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Acta Mathematica Sinica,English Series 2024年第3期40卷 731-771页

作者： alexander HAZELTInE Bai Ying LIU Department of Mathematics Purdue University150 N.University St.West LafayetteIN 47907USA E-mail:ahazelti@purdue.edu liu2053@purdue.edu

We prove a converse theorem for split even special orthogonal groups over finite fields.This is the only case left on converse theorems of classical groups and the difficulty is the existence of the outer automorphism... 详细信息

关键词： Converse theorems generic cuspidal representations even special orthogonal groups

The Effect of a Monatomic Layer on a Surface on the Transition Radiation

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 710-723页

作者： alexander n. Safronov Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow Russia

The transition radiation of a charged particle crossing the interface of two media having a monatomic impurity layer is investigated. It is shown that at sliding angles of incidence of a particle on the boundary of the media, the transition radiation is mainly determined by the properties of the surface layer. The possibility of using transition radiation to study the surface of substances is discussed. In addition, due to the hard radiation present in space, this research may be important for the use of light monoatomic layers as a material for satellite antennas, “solar sails” and cover layers in a future space (interstellar) mission.

关键词： Relativistic Charged Particle Transition Radiation Monatomic Layer Spectral Angular Distribution of Radiation Sliding Angle Investigation of Thin Films Interstellar Mission

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

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: II. Scanning for Habitable Stellar Systems on Behalf of Future Space Missions

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第2期10卷 681-692页

作者： alexander n. Safronov Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow Russia

The possibility of the life origin in the stellar systems, located at a distance of ~200 pc from the solar system, was investigated. The stars, in the spectrums of which C (carbon), O (oxygen), n (nitrogen), and P (phosphorus) are found, are called DnA-stars. Based on stellar abundances a new method for searching for habitable exoplanets has been developed and a list of 48 DnA-stars in the solar neighborhood, on which life is possible, has been defined. The quota of DnA-stars is equal 1.3% of the total amount of Hypatia Stellar Catalog. Only three DnA-stars out of selected 48 stars belong to the spectral class as our Sun (G2V). The closest to the solar system is the DnA-star with the number HIP 15510, which belongs to the G8V class and is 6 pc away from the solar system. nine DnA-stars, which have the highest chemical similarity with solar spectrum, were identified. It is identified that one of these nine stars, HIP 24681, has six planets.

关键词： Interstellar Mission Stellar Abundance Habitability Hypatia Stellar Catalog DnA-Star

Atherosclerosis originating from childhood:Specific features

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Journal of Biomedical Research 2024年第3期38卷 233-240页

作者： Anastasia V.Poznyak Alexey A.Yakovlev MikhailА.Popov Elena B.Zhigmitova Vasily n.Sukhorukov alexander n.Orekhov Institute for Atherosclerosis Research Moscow 121609Russia Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology Moscow 109240Russia Department of Cardiac Surgery Moscow Regional Research and Clinical InstituteMoscow 129110Russia Laboratory of Angiopathology Institute of General Pathology and PathophysiologyMoscow 125315Russia

Atherosclerosis is extremely widespread.Traditionally,it is considered a disease of older people,who most often experience problems with the heart and blood vessels.While much attention from the scientific community has been paid to studying the association between aging and atherosclerosis,as well as its consequences,there is evidence that atherosclerosis occurs at an early age.Atherosclerosis may form both during intrauterine development and in childhood.nutrition plays an important role in childhood atherosclerosis,along with previous infectious diseases and excess weight of both the child and the mother.In the present review,we examined the development of atherosclerosis and the prerequisites in childhood.

关键词： atherosclerosis childhood pediatrics cardiovascular disease