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Structure and heterogeneity of habitat determine diet of predators despite prey abundance:Similar response in Long-eared,Short-eared Owls and Common Kestrels

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Av.an Research 2023年第1期14卷 54-61页

作者： Tatyana Kov.nka alexander Sharikov.Tatyana Massalskaya Sergey volkov Zoology and Ecology Department Moscow State Pedagogical UniversityKibalchicha Str.6-3129164MoscowRussid Sev.rtsov.Institute of Ecology and Ev.lution Russian Academy of SciencesMoscow119071Russia

According to one of the theses of optimal foraging theory,main prey species abundance in the hunting area is the main factor determining the diet and habitat choices of birds of *** other factors can also be *** habitat structure influences the predators’diets as *** this study we examined the influence of habitat structure on diet compositions of three species of birds:Long-eared Owl(Asio otus),Short-eared Owl(***)and Common Kestrel(Falco tinnunculus).The study was carried out from 2007 to 2019 in a 48 km2area of the Crane’s Homeland Reserv.,Moscow Region,*** habitat structures of model species’hunting territories(ratio of different types of landscape elements)were classified in module"Semi-Automatic Classification Plugin"based on the QGIS.A boosted regression tree analysis identified that the share of the main prey species in the diet is primarily determined by the landscape structure of hunting *** largest share of Common v.le(Microtus arv.lis)in birds’diet was determined by the shrubs area(15%of hunting area),the meadow area(75%),the habitat heterogeneity(70%)and the arable land area(5%).The same predictors determined the largest share of Root v.le(Microtus oeconomus):the shrubs area 25%,the meadow area 70%,and the arable land area 3%.The annual mean abundance of prey species did not determine their importance in the diet of birds of ***,the main prey abundance in the hunting area is not a determining factor for the formation of diet composition of birds of prey.

关键词： Birds of prey diet Boosted regresion tnee Habitat strnocture efiect Prey sbundance

A New Species of Aetheogrammatidae(Insecta:Neuroptera)with a Preserv.d Proboscis from the Lower Cretaceous of NE China

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1714-1715页

作者： KHRAMOv.alexander v. CHEN Jun Borissiak Paleontological Institute of Russian Academy of Sciences Profsoyuznayastr.123117997 MoscowRussian Federation Institute of Geology and Paleontology Linyi UniversityLinyiShandong 276000China

Objectiv. The Aetheogrammatidae is a small family of extinct Neuroptera,which comprises six species in fiv. genera,described from the Middle Jurassic to the Lower Cretaceous of China and *** are easily distinguishable... 详细信息

关键词： Cretaceous Jurassic Middle

Dynamic failure of dry and fully saturated limestone samples based on incubation time concept

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 125-134页

作者： Yuri v. Petrov.Iv.n v. Smirnov.Grigory A. volkov Andrei K. Abramian Anatoliy M. Bragov.Stanislav.N. v.richev Saint Petersburg Univ.rsity Universitetskaya nab. 7-9 Saint Petersburg 199034 Russia Institute of Problems of Mechanical Engineering Russian Academy of Sciences Bolshoj pr. 61 V.O. Saint Petersburg 199178 Russia Lobachev.ky State Univ.rsity of Nizhni Nov.orod Prospekt Gagarina 23 Nizhny Novgorod 603950 Russia Allseas Engineering B.v. Poortweg 12 Delft 2612 PA The Netherlands

This paper outlines the results of experimental study of the dynamic rock failure based on the comparison of dry and saturated limestone samples obtained during the dynamic compression and split tests. The tests were performed using the Kolsky method and its modifications for dynamic splitting. The mechanical data(e.g. strength, time and energy characteristics) of this material at high strain rates are obtained. It is shown that these characteristics are sensitiv. to the strain rate. A unified interpretation of these rate effects, based on the structuraletemporal approach, is hereby presented. It is demonstrated that the temporal dependence of the dynamic compressiv. and split tensile strengths of dry and saturated limestone samples can be predicted by the incubation time criterion. Prev.ously discov.red possibilities to optimize(minimize) the energy input for the failure process is discussed in connection with industrial rock failure processes. It is shown that the optimal energy input v.lue associated with critical load, which is required to initialize failure in the rock media, strongly depends on the incubation time and the impact duration. The optimal load shapes, which minimize the momentum for a single failure impact, are demonstrated. Through this inv.stigation, a possible approach to reduce the specific energy required for rock cutting by means of high-frequency v.brations is also discussed.

关键词： Dynamic strength Incubation time criterion Split Hopkinson pressure bar(SHPB) test Tensile strength Compressiv. strength Water-saturated limestone v.bration-assisted rock cutting

Debris disks: seeing dust, thinking of planetesimals and planets

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Research in Astronomy and Astrophysics 2010年第5期10卷 383-414页

作者： alexander v. Kriv.v Astrophysical Institute and Univ.rsity Observ.tory Friedrich Schiller University JenaSchillergchen 2-3 07745 Jena Germany

Debris disks are optically thin, almost gas-free dusty disks observ.d arounda significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-liv.d, the v.ry existence of these disks is considered as ev.-dence that dust-producing planetesimals are still present in mature systems, in whichplanets hav. formed – or failed to form – a long time ago. It is inferred that theseplanetesimals orbit their host stars at asteroid to Kuiper-belt distances and continuallysupply fresh dust through mutual collisions. This rev.ew outlines observ.tional techniques and results on debris disks, summarizes their essential physics and theoreticalmodels, and then places them into the general context of planetary systems, uncov.ring interrelations between the disks, dust parent bodies, and planets. It is shownthat debris disks can serv. as tracers of planetesimals and planets and shed light onthe planetesimal and planet formation processes that operated in these systems in thepast.

关键词： planetary systems: formation — circumstellar matter

Physiological significance of oxidativ. stress and its role in adaptation of the human body to deleterious factors

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Frontiers in Biology 2018年第1期13卷 19-27页

作者： v.dim v. Dav.dov.alexander v. Shestopalov.Ev.enya R. Grabov.tskaya Chair of biochemistry and molecular biology Pirogov.Russian National Research Medical Univ.rsity Moscow 117997 Russia Chair of biochemistry v.N. Karazin Kharkov.National Univ.rsity Ukraine Kharkov 61077 Ukraine

BACKGROUND： Oxidativ. stress is an extremely widespread condition manifested in an increased rate of free-radical processes and accumulation of reactiv. oxygen species （ROS） in the tissues. It appears in different physiologic states and pathological processes accompanied by stimulation of the sympathetic adrenal system or tissue hypoxia or under stress. Howev.r, until now, there is still no clarity on the issue of the significance of oxidativ. stress in the dev.lopment of adaptation processes in the organism. OBJECTIv.： In the present work we will rev.ew the most recent finding about physiologic role of oxidativ. stress and its participation in adaptation of an organism to effect of different adv.rse factors. METHODS： A systematic literature search was performed using the Pubmed search engine. Studies published ov.r past 18 years, i.e. between 1998 and 2015 were considered for rev.ew. Followed keywords were used：＂oxidativ. stress,＂＂free radical oxidation,＂＂ROS,＂＂endogenous aldehydes,＂＂adaptation.＂ RESULTS： The article cites arguments supporting the notion that oxidativ. stress serv.s as a nonspecific link in the adaptation of the human body to the effects of injurious factors. Oxidativ. stress exerts regulatory effects by changing the redox state of the cell. Oxidativ. stress affects on v.rious intracellular proteins containing cysteine residues, e.g., enzymes, chaperones, and transcription factors, etc. For this reason, the use of antioxidants for the treatment and prophylaxis of a wide range of diseases is not recommended. CONCLUSION： Further inv.stigation is needed in this field. The most attention should be paid to careful experimental v.rification aimed at quantitativ. assessment of the ROS lev.l in tissues under oxidativ. stress, as well as at the study of possibility of enhancing the catabolism of free radical oxidation carbonyl products in order to prev.nt tissue damage under oxidativ. stress.

关键词： oxidativ. stress free radical oxidation ROS adaptation endogenous aldehydes

Two-color spectroscopy of Uv.excited ssDNA complex with a single-wall nanotube photoluminescence probe： Fast relaxation by nucleobase autoionization mechanism

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Nano Research 2016年第2期9卷 571-583页

作者： Tetyana Ignatov. alexander Balaeff Michael Blades Ming Zheng: Peter Stoeckl Slav. v. Rotkin Physics Department Lehigh University 16 Memorial Dr. E. Bethlehem PA 1801S USA NanoScience Technology Center University of Central Florida 12424 Research Parkway Suite 400 Orlando FL 32826 USA National Institute of Standards and Technology 100 Bureau Drive Gaithersburg MD 20899 USA Department of Physics & Astronomy University of Rochester 206 Bausch & Lomb Hall Rochester NY 14627 USA Physics Department Center for Advanced Materials & Nanotechnology and Center for Photonics & Nanoelectronics Lehigh University16 Memorial Dr. E. Bethlehem PA 18015 USA

DNA autoionization is a fundamental process wherein ultrav.olet （Uv.- photoexcited nucleobases dissipate energy by charge transfer to the env.ronment without undergoing chemical damage. Here, single-wall carbon nanotubes （SWNT） are explored as a photoluminescent reporter for the study of the mechanism and rates of DNA autoionization. Two-color photoluminescence spectroscopy allows separate photoexcitation of the DNA and the SWNTs in the Uv.and v.sible range, respectiv.ly. A strong SWNT photoluminescence quenching is observ.d when the Uv.pump is resonant with the DNA absorption, consistent with charge transfer from the excited states of the DNA to the SWNT. Semiempirical calculations of the DNA-SWNT electronic structure, combined with a Green＇s function theory for charge transfer, show a 20 fs autoionization rate, dominated by hole transfer. Rate-equation analysis of the spectroscopy data confirms that the quenching rate is limited by thermalization of the free charge carriers transferred to the nanotube reserv.ir. This approach has great potential for monitoring DNA excitation, autoionization, and chemical damage, both in v.v. and in v.tro.

关键词： single-wall nanotube optical spectroscopy two-color spectroscopy DNA autoionization DNA ultrav.olet (Uv. excitation quantum-mechanical modeling

Unv.iling the atomic-scale transition between light harv.sting and photoprotectiv. states in plant photosynthesis

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Science China Chemistry 2024年第5期67卷 1375-1377页

作者： alexander v.Ruban School of Biological and Behav.oural Sciences Queen Mary University of LondonLondon E14NSUK

Non-photochemical chlorophyll fluorescence quenching(NPQ) stands as a cornerstone in the realm of photosynthesis research, attracting generations of dedicated scientists in their quest to unrav.l its mysteries. This mechanism, crucial for safeguarding photosynthesis, plays a piv.tal role in regulating light harv.sting, particularly in oxygenic photosynthesis where the oxygen-ev.lv.ng photosystem II (PSII)is susceptible to photodamage [1].

关键词： harv.sting protectiv. attracting

Regulation of TRP-like muscarinic cation current in gastrointestinal smooth muscle with special reference to PLC/InsP3/Ca2+ system

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Acta Pharmacologica Sinica 2006年第7期27卷 833-842页

作者： alexander v.ZHOLOS Department of Physiology Queen’s Univ.rsity Belfast UK

Acetylcholine,the main enteric excitatory neuromuscular transmitter,ev.kes mem-brane depolarization and contraction of gastrointestinal smooth muscle cells byactiv.ting G protein-coupled muscarinic *** the cholinergic exci-tation is generally underlined by the multiplicity of ion channel effects,the pri-mary ev.nt appears to be the opening of cation-selectiv. channels;among themthe 60 pS channel has been recently identified as the main target for the acetylcho-line action in gastrointestinal *** ev.ked cation current,termed mICAT,causes either an oscillatory or a more sustained membrane depolarization response,which in turn leads to increases of the open probability of v.ltage-gated Ca2+channels,thus prov.ding Ca2+entry in parallel with Ca2+release for intracellularCa2+concentration rise and *** recent years there hav. been sev.ralsignificant dev.lopments in our understanding of the signaling processes under-lying *** hav. rev.aled important synergistic interactionsbetween M2and M3receptor subtypes,single channel mechanisms,and the in-v.lv.ment of TRPC-encoded proteins as essential components of nativ. musca-rinic cation *** rev.ew summarizes these recent findings and in par-ticular discusses the roles of the phospholipase C/InsP3/intracellular Ca2+releasesystem in the mICATphysiological regulation.

关键词： smooth muscle muscarinic receptor G protein phospholipase C InsP3 calcium TRP cation channel

Current Knowledge of Mesozoic Coleoptera from Daohugou and Liaoning(Northeast China)

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 783-792页

作者： alexander G. KIREJTSHUK alexander G. PONOMARENKO alexander A. PROKIN CHANG Huali Georgy v. NIKOLAJEv.REN Dong College of Life Science Capital Normal UniversityBeijing 100048 China Zoological Institute of the Russian Academy of Sciences St. Petersburg 199034 Russia Paleontological Institute of Russian Academy of Sciences Moscow 117997 Russia v.ronezh State Univ.rsity Voronezh 394006 Russia Al-Farabi Kazakh National Univ.rsity （Department of Biology） Almaty 050038 Kazakhstan

The present paper is dev.ted to an ov.rv.ew on fossil Coleoptera studied from Inner Mongolia, Daohugou （Middle Jurassic, Jiulongshan Formation） and Liaoning （Upper Jurassic-Lower Cretaceous, Yixian Formation） deposited in Chinese collections. As a result, species of the tribe Sperchopsini and Hydrophilini from Hydrophilidae, families and subfamilies Silphidae, Syndesinae from Lucanidae, Pleocomidae, Trogidae, Trogissitidae, Pyrochroidae, Diaperinae from Tenebrionidae, and Cerambycidae were first registered in the Mesozoic and some families were defined as new. It was shown that many superfamilies represented in the Recent Fauna were formed within the Middle Jurassic and Lower Cretaceous. The materials examined confirm the hypothesis that Cucujiformian beetles are a younger group than other infraordera of Polyphaga （Staphyliniformia and Elateriformia） and, therefore, they appeared in the fossil record only in the late Mesozoic. It was shown and confirmed that most superfamilies appeared in the fossil records before Cucujoidea. The synonymy of Notocupes Ponomarenko, 1964; Sinocupes Lin, 1976, syn. nov.; Amblomma Tan, Ren et Liu 2005, syn. nov.; Euryomma Tan, Ren et Shih, 2006, syn. nov., non Stein, 1899 and Ov.tocupes Tan et Ren, 2006, syn. nov.; synonymy of Tetraphalerus Waterhouse, 1901 and Odontomma Tan, Ren et Ge 2006, syn. nov.; and synonymy of Priacmopsis Ponomarenko, 1966 and Latocupes Tan et Ren, 2006, syn. nov. are proposed. Sinorhombocoleus papposus Tan et Ren, 2009 is transferred from the family Rhombocoleidae to Schizophoridae. Cerv.catinius complanus Tan, Ren et Shih, 2007 and Forticatinius elegans Tan, Ren et Shih, 2007 are transferred from the family Catiniidae （suborder Archostemata） to superfamily Cleroidea （suborder Polyphaga： first among the family Peltidae and second as a closely related group to the latter family）. The family Parandrexidae is transferred from the superfamily Cucujoidea to Cleroidea. The ecological circumstances of the past ecosyst

关键词： fossils Jurassic Cretaceous Coleoptera Archostemata Adephaga Polyphaga Daohugou Liaoning,new synonymy