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Trapped on the Roof of the World:taxonomic diversity and evolutionary patterns of Tibetan Plateau endemic freshwater snails(Gastropoda:Lymnaeidae:Tibetoradix)

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Integrative Zoology 2022年第5期17卷 825-848页

作者： Maxim V.VInARSKI Parm Viktor VOn OHEIMB Olga V.AKSEnOVA Mikhail Yu.GOFAROV Alexander V.KOnDAKOV ivan O.nEKHAEV ivan n.bolotov Laboratory of Macroecology and Biogeography Saint-Petersburg State UniversitySaint-PetersburgRussia Museum für naturkunde-Leibniz Institute for Evolution and Biodiversity Science BerlinGermany n.Laverov Federal Center for Integrated Arctic Research of the Ural Branch of the Russian Academy of Sciences ArkhangelskRussia Department of Applied Ecology Saint-Petersburg State UniversitySaint-PetersburgRussia northern(Arctic)Federal University ArkhangelskRussia

The high-elevation Tibetan Plateau(western China)is inhabited by a unique,though not particularly species-rich,community of *** explored the species content and evolutionary history of the Tibetan Plateau endemic freshwater snail genus *** relationships within the genus were reconstructed based on available sequence *** used a single-rate Poisson Tree Processes approach for species delimitation and compared putative species-level clades with already described *** found that the genus consists of at least 6 species,of which we described 4 as new to *** and soft body morphology was examined and the radula in Tibetoradix was described for theﬁrst *** on ourﬁndings,the diversiﬁcation of the genus did not result in a prominent morphological differentiation and a number of species can be regarded as morphologically *** species found in different drainage areas indicate relatively good passive dispersal abilities of the *** allopatric distribution of the species could result from competitive exclusion between *** absence of Tibetoradix *** the Tibetan Plateau could be explained by a scenario of an“evolutionary trap”,where adaptations to high elevation conditions prevented the taxa from a successful colonization of lower elevations.

关键词： biogeography High Asia molecular phylogenetics morphology species delimitation

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neuroprotective therapy for retinal neurodegenerative diseases by stem cell secretome

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neural Regeneration Research 2021年第1期16卷 117-118页

作者： Ricardo Usategui-Martín ivan Fernandez-Bueno Instituto Universitario de Oftalmobiología Aplicada(IOBA) Retina GroupUniversidad de ValladolidValladolidSpain Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y León Red Temática de Investigación Cooperativa en SaludOftaredInstituto de Salud Carlos IIIValladolidSpain

Retinal neurodegenerative diseases like agerelated macular degeneration,glaucoma,diabetic retinopathy or retinitis pigmentosa are the most frequent causes of incurable low vision and blindness *** had been estimated that the prevalence of these diseases varies between 1/750 and 1/5000 depending on the region,the level of consanguinity or ethnicity(na et al.,2017).The functional and structural complexity of the retina makes it susceptible to multiple types of pathogenic damage.

关键词： diseases protective degenerative

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Solar flares with similar soft but different hard X-ray emissions： case and statistical studies

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Research in Astronomy and Astrophysics 2016年第1期16卷 39-50页

作者： ivan n.Sharykin Alexei B.Struminsky ivan V.Zimovets Wei-Qun Gan Space Research Institute Russian Academy of Sciences Moscow 117997 Russia Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

From the Reuven Ramaty High Energy Solar Spectroscopic Imager （RHESS1） catalog we select events which have approximately the same GOES class （high C - low M or 500-1200 counts s-1 within the RHESSI 6-12 keV energy band）, but with different maximal energies of detected hard X-rays. The selected events are subdivided into two groups：（1） flares with X-ray emissions observed by RHESSI up to only 50 keV and （2） flares with hard X-ray emission observed also above 50 keV. The main task is to understand observational peculiarities of these two flare groups. We use RHESSIX-ray data to obtain spectral and spa- tial information in order to find differences between selected groups. Spectra and images are analyzed in detail for six events （case study）. For a larger number of samples （85 and 28 flares in the low-energy and high-energy groups respectively） we only make some generalizations. In spectral analysis we use the thick- target model for hard X-ray emission and one temperature assumption for thermal soft X-ray emission. RHESSI X-ray images are used for determination of flare region sizes. Although thermal and spatial prop- erties of these two groups of flares are not easily distinguishable, power law indices of hard X-rays show significant differences. Events from the high-energy group generally have a harder spectrum. Therefore, the efficiency of chromospheric evaporation is not sensitive to the hardness of nonthermal electron spectra but rather depends on the total energy flux of nonthermal electrons.

关键词： Sun: flares -- Sun: X-rays -- gamma rays

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One-Generated nilpotent Bicommutative Algebras

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Algebra Colloquium 2022年第3期29卷 453-474页

作者： ivan Kaygorodov Pilar Páez-Guillán Vasily Voronin Centro de Matemática e Aplicacōes Universidade da Beira InteriorCovilhãPortugal Institute of Mathematics and Mathematical ModelingAlmatyKazakhstan University of Santiago de Compostela Santiago de CompostelaSpain University of ViennaViennaAustria novosibirsk State University NovosibirskRussia

We give a classification of 5-and 6-dimensional complex one-generated nilpotent bicommutative algebras.

关键词： bicommutative algebras nilpotent algebras algebraic classification central extension

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Discrimination of ventricular tachycardia and localization of its exit site using surface electrocardiography

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Journal of Geriatric Cardiology 2019年第4期16卷 362-377页

作者： Heber ivan Condori Leandro Dmitry S Lebedev Evgeny n Mikhaylov Lang G.F. department of Internal Medicine Pavlov First Saint Petersburg State Medical UniversitySaint-PetersburgRussia Almazov national Medical Research Centre Saint-PetersburgRussia Department of Medical and Biotechnology Systems First Electrotechnical UniversitySaint-PetersburgRussia

Differential diagnosis of supraventricular tachycardia (SVT) and ventricular tachycardia (VT) is of paramount importance for appropriate patient management. Several diagnostic algorithms for discrimination of VT and SVT based on surface electrocardiogram (ECG) analysis have been proposed. Following established diagnosis of VT,a specific origination tachycardia site can be supposed according to QRS complex characteristics. This review aims to cover comprehensive and comparative description of the main VT diagnostic algorithms and to present ECG characteristics which permit to suggest the most common VT origination sites.

关键词： Arrhythmias Electrocardiogram Supraventricular Tachycardia Ventricular

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Phylogenetic Relationships of 3/3 and 2/2 Hemoglobins in Archaeplastida Genomes to Bacterial and Other Eukaryote Hemoglobins

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Molecular Plant 2011年第1期4卷 42-58页

作者： Serge n. Vinogradov ivan Fernandez David Hoogewijs Rail Arredondo-Peter Department of Biochemistry and Molecular Biology Wayne State University School of Medicine Detroit MI 48201 USA Laboratorio de Biofisica y Biologia Molecular Facultad de Ciencias Universidad Autonoma del Estado de Morelos 62210 Cuernavaca Morelos Mexico Institute of Physiology and Zurich Center for Integrative Human Physiology (ZIHP) University of Zurich Zurich Switzerland

Land plants and algae form a supergroup, the Archaeplastida, believed to be monophyletic. We report the results of an analysis of the phylogeny of putative globins in the currently available genomes to bacterial and other eu- karyote hemoglobins （Hbs）. Archaeplastida genomes have 3/3 and 2/2 Hbs, with the land plant genomes having group 2 2/ 2 Hbs, except for the unexpected occurrence of two group 1 2/2 Hbs in Ricinus communis. Bayesian analysis shows that plant 3/3 Hbs are related to vertebrate neuroglobins and bacterial flavohemoglobins （FHbs）. We sought to define the bacterial groups, whose ancestors shared the precursors of Archaeplastida Hbs, via Bayesian and neighbor-joining anal- yses based on COBALTalignment of representative sets of bacterial 3/3 FHb-like globins and group I and 2 2/2 Hbs with the corresponding Archaeplastida Hbs. The results suggest that the Archaeplastida 3/3 and group 1 2/2 Hbs could have orig- inated from the horizontal gene transfers （HGTs） that accompanied the two generally accepted endosymbioses of a pro- teobacterium and a cyanobacterium with a eukaryote ancestor. In contrast, the origin of the group 2 212 Hbs unexpectedly appears to involve HGT from a bacterium ancestral to Chloroflexi, Deinococcales, Bacilli, and Actinomycetes. Furthermore, although intron positions and phases are mostly conserved among the land plant 3/3 and 2/2 globin genes, introns are absent in the algal 3/3 genes and intron positions and phases are highly variable in their 2/2 genes. Thus, introns are irrelevant to globin evolution in Archaeplastida.

关键词： Algae Archaeplastida evolution hemoglobin land plants truncated Hbs

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Single-atom spintronics

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中国有色金属学会会刊：英文版 2006年第B1期16卷 146-153页

作者： Susan Z.HUA Matthew R.SULL ivan Jason n.ARMSTROnG Materials Program Mechanical and Aerospace Engineering DepartmentState University of New York at BuffaloBuffaloNY 14260USA

Recent work on magnetic quantum point contacts (QPCs) was discussed. Complete magnetoresistance loops across Co QPCs as small as a single atom was measured. The remarkable feature of these QPCs is the rapid oscillatory decay in magnetoresistance with the increase of contact size. In addition, stepwise or quantum magnetoresistance loops are observed, resulting from varying transmission probability of the available discrete conductance channels because the sample is cycled between the ferromagnetic (F) and antiferromagnetic (AF) aligned states. Quantized conductance combined with spin dependent transmission of electron waves gives rise to a multi-channel system with a quantum domain wall acting as a valve, i.e., a quantum spin-valve. Behavior of a few-atom QPC is built on the behavior of a single-atom QPC and hence the summarization of results as ‘single-atom spintronics’. An evolutionary trace of spin-dependent electron transmission from a single atom to bulk is provided, the requisite hallmarks of artefact-free magnetoresistance is established across a QPC – stepwise or quantum magnetoresistance loops and size dependent oscillatory magnetoresistance.

关键词：单原子自旋电子学量子点接触电子波导振荡磁阻

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LOW-RAnK TEnSOR STRUCTURE OF SOLUTIOnS TO ELLIPTIC PROBLEMS WITH JUMPInG COEFFICIEnTS

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Journal of Computational Mathematics 2012年第1期30卷 14-23页

作者： Sergey Dolgov Boris n.Khoromskij ivan Oseledets Eugene E.Tyrtyshnikov Moscow Institute of Physics and Technology Russia Max-Planck-Institute for Mathematics in Sciences Inselstr.22-26D-04103 LeipzigGermany Institute of numerical Mathematics Russian Academy of SciencesGubkina 8119991 MoscowRussia Lomonosov Moscow State University Russia University of Siedlce Poland(visiting professor)

We study the separability properties of solutions to elliptic equations with piecewise constant coefficients in Rd, d ≥ 2. The separation rank of the solution to diffusion equation with variable coefficients is prese... 详细信息

关键词： Structured matrices Elliptic operators Poisson equation Matrix approxima-tions Lowrank matrices Tensors Canonical decomposition.

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Intravitreal stem cell paracrine properties as a potential neuroprotective therapy for retinal photoreceptor neurodegenerative diseases

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neural Regeneration Research 2020年第9期15卷 1631-1638页

作者： Kevin Puertas-neyra Ricardo Usategui-Martín Rosa MCoco ivan Fernandez-Bueno Instituto Universitario de Oftalmobiologia Aplicada Universidad de ValladolidValladolidSpain Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y Leon ValladolidSpain Red Tematica de Investigacion Cooperativa en Salud OftaredInstituto de Salud CarlosⅢValladolidSpain

Retinal degenerations are the leading causes of irreversible visual loss worldwide. Many pathologies included under this umbrella involve progressive degeneration and ultimate loss of the photoreceptor cells, with age-related macular degeneration and inherited and ischemic retinal diseases the most relevant. These diseases greatly impact patients' daily lives, with accompanying marked social and economic consequences. However, the currently available treatments only delay the onset or slow progression of visual impairment, and there are no cures for these photoreceptor diseases. Therefore, new therapeutic strategies are being investigated, such as gene therapy, optogenetics, cell replacement, or cell-based neuroprotection. Specifically, stem cells can secrete neurotrophic, immunomodulatory, and anti-angiogenic factors that potentially protect and preserve retinal cells from neurodegeneration. Further, neuroprotection can be used in different types of retinal degenerative diseases and at different disease stages, unlike other potential therapies. This review summarizes stem cell-based paracrine neuroprotective strategies for photoreceptor degeneration, which are under study in clinical trials, and the latest preclinical studies. Effective retinal neuroprotection could be the next frontier in photoreceptor diseases, and the development of novel neuroprotective strategies will address the unmet therapeutic needs.

关键词： clinical trials growth factors intraocular injection intravitreal injection neuroprotection paracrine properties photoreceptors preclinical models retinal diseases stem cells

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Structural Changes and Electrodynamic Effects in Polymers under Fast Uniaxial Compression

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Chinese Journal of Polymer Science 2021年第5期39卷 601-609,I0007页

作者： Aleksey.I.Aleksandrov ivan A.Aleksandrov Vitaliy G.Shevchenko Aleksandr n.Ozerin n.S.Enikolopov Institute of Synthetic Polymeric Materials RAS 117393 Moscow Profsoyuznaya70 Russian Federation

Rheological explosion in polymers under uniaxial compression in an open volume occurs at the end of continuous rapid plastic deformation after several stages of *** types of polymers were chosen for this study:brittle glassy amorphous polystyrene and thermoplastic semi-crystalline *** pulses were detected during explosion,and their spectra were analyzed with two models.X-ray diffraction methods were used to investigate changes in the structure and morphology of polymers during deformation and rheological *** pores appear in polymer in this process,and their shape and size distribution were derived from X-ray *** main reason for the formation of pores in polymer samples in rheological explosion experiments is the intense microshifts in the polymer volume under the action of high applied pressure.

关键词： Polystyrene Polypropylene X-ray Mechanical properties Compression

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