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Early Miocene flora of central Kazakhstan(Turgai Plateau) and its paleoenvironmental implications

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Plant Diversity 2019年第3期41卷 183-197页

作者： popova Svetlana Utescher Torsten Averyanova Anna Tarasevich valentina Tropina polina Xing Yaowu Komarov Botanical Institute of RAS Palaeobotanical Department 2 Professor Popov Str. Saint Petersburg 197376 Russia Steinmann Institute Bonn University Nussallee 8 Bonn D-53115 Germany Senckenberg Research Institute and Natural History Museum/Biodiversity and Climate Research Centre Senckenberganlage 25 Frankfurt D-60325 Germany Xishuangbanna Tropical Botanical Garden of Chinese Academy of Sciences (CAS) Menglum Mengla Yunnan 666303 China

The investigation of the fossil floras from the Turgai plateau (central Kazakhstan) contributes to a better understanding of the origin of the temperate Turgai type flora which spread to Kazakhstan and adjacent areas during the Oligocene-Miocene transition. In this paper, we present the results of a carpological and palynological study of the Kumyrtas flora collected from a flora-bearing horizon of the regional coalbearing Zhilanchik suite, dated to the Aquitanian period. Pollen analysis identified 33 taxa, with are dominated by angiosperms (about 73%) and reflect zonal vegetation. The high percentages of Betula (27%) and Pterocarya (7.5%) that were found in this flora allows comparisons with other Aquitanian floras of Kazakhstan. Based on descriptions of fossil fruits and seeds, we determined that 19 taxa were dominant;these taxa had meosphytic herbaceous components, suggesting mostly edaphic local conditions. The incongruence between the carpological and the pollen records suggests a significant taphonomical effect. Quantitative reconstruction of the palaeoclimate based on pollen records supports—and slightly extends—previous findings based on fossil leaf data, but contradicts findings deduced from the carpological record. Plant Functional Type (PFT) classification was used to characterize the vegetation patterns. Pollen records show that about 45% of diversity relates to the arboreal broadleaved deciduous components and ca. 35% to conifers. Fossil fruit and seed data indicate riverine vegetation with a high diversity of aquatic components and shrub stratum.

关键词： Kazakhstan Turgai flora Oligocenee-Miocene transition Palaeoclimate reconstruction PFT

Ketogenic diet versus ketoacidosis： what determines the influence of ketone bodies on neurons？

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Neural Regeneration Research 2018年第12期13卷 2060-2063页

作者： Sergei v.Fedorovich polina P.voronina Tatyana v.Waseem Institute of Biophysics and Cell Engineering Minsk Belarus Department of Pharmacology University of Oxford Oxford UK

Glucose is the main energy substrate for neurons, however, at certain conditions, e.g. in starvation, these cells could also use ketone bodies. This approach is used in clinical conditions as the ketogenic diet. The ketogenic diet is actually a biochemical model of fasting. It includes replacing carbohydrates by fats in daily meal. Synthesis of ketone bodies β-hydroxubutirate, acetoacetate and acetone begins once glycogen stores have depleted in the liver. The ketogenic diet can be used to treat clinical conditions, primarily epilepsy. The mechanism of neuroprotective action of ketogenic diet is not very clear. It is shown that ketone bodies influence neurons at three different levels, namely, metabolic, signaling and epigenetic levels. Ketone bodies are not always neuroprotective. Sometimes they can be toxic for the brain. Ketoacidosis which is a very dangerous complication of diabetes mellitus or alcoholism can be taken as an example. The exact mechanism of how neuroprotective properties of ketone bodies reverse to neurotoxic is yet to be established.

关键词： β-hydroxybutirate epilepsy diabetes mellitus alcoholism metabolism hydroxyl-carboxylic acid receptor epigenetics acidosis

Crystal-field levels of Nd3+ in a new langasite compound Nd3CrGe3Be2O14

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Journal of Rare Earths 2019年第11期37卷 1250-1254页

作者： Sergei A.Klimin Boris v.Mill Marina N.popova Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia

We report on the crystal-field(CF)levels of Nd^3+in Nd3CrGe3Be2O14,a representative of recently synthesized Be-containing *** are the first in the family to contain two magnetic subsystems,1 D chromium and Kagome-like rare-earth ***-resolution broad-band temperature-dependent spectra allow us to find all five CF Kramers doublets of the ground 4I9/2 CF multiplet and 38 levels of the excited 4I11/2,13/2,15/2,4F3/2,4F5/2+2H9/2,4F7/2+4S3/2 and 4F9/2 CF *** data form a basis for a future exploration of this interesting two-sublattice magnet with frustrated *** transitions between Kramers doublets of Nd^3+indicate magnetic activity of 1D-chromium chains at T<20 K.

关键词： Langasite Two magnetic subsystems High-resolution spectroscopy Crystal-field levels Magnetic correlations Rare earths

The RdDM Pathway Is Required for Basal Heat Tolerance in Arabidopsis

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Molecular Plant 2013年第2期6卷 396-410页

作者： Olga v. popova Huy Q. Dinh Werner Aufsatz Claudia Jonak GMI-Gregor Mendel Institute of Molecular Plant Biology Austrian Academy of Sciences Dr. Bohr-Gasse 3 1030 Vienna Austria

Heat stress affects epigenetic gene silencing in Arabidopsis. To test for a mechanistic involvement of epige-netic regulation in heat-stress responses, we analyzed the heat tolerance of mutants defective in DNA methylation, his-tone modifications, chromatin-remodeling, or siRNA-based silencing pathways. Plants deficient in NRPD2, the common second-largest subunit of RNA polymerases Iv and v, and in the Rpd3-type histone deacetylase HDA6 were hypersensi- tive to heat exposure. Microarray analysis demonstrated that NRPD2 and HDA6 have independent roles in transcriptional reprogramming in response to temperature stress. The misexpression of protein-coding genes in nrpd2 mutants recover-ing from heat correlated with defective epigenetic regulation of adjacent transposon remnants which involved the loss of control of heat-stress-induced read-through transcription. We provide evidence that the transcriptional response to temperature stress, at least partially, relies on the integrity of the RNA-dependent DNA methylation pathway.

关键词： heat stress RNA-directed DNA methylation transposons read-through transcription.

Introduction to the Special Issue on Advances in Biophotonics and Biomedical Optics:Part II

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 29-31页

作者： polina Dyachenko(Timoshina) Tingting Yu Dan Zhu valery v.Tuchin Research-Educational Institute of Optics and Biophotonics Saratov State University Saratov 410012Russia Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 P.R.China MoE Key Laboratory for Biomedical Photonics School of Engineering Sciences Huazhong University of Science and Technology Wuhan 430074 P.R.China

The 9th Chinese–Russian Workshop on Biophotonics and Biomedical Optics was held online on 28–30 September *** bilateral workshop brought together both Russian and Chinese scientists,engineers,and clinical researchers from a variety of disciplines engaged in applying optical science,photonics,and imaging technologies to problems in biology and *** the workshop,2 plenary lectures,35 invited presentations,5 oral presentations,and 8 internet reports were *** special issue selects some papers from the attendees and includes both research and review articles.

关键词： photonics Russian Biomedical

Evidences for non-equivalent centers in mixed chain nickelates (Nd_xY_(1-x))_2BaNiO_5

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Journal of Rare Earths 2009年第4期27卷 603-606页

作者： M.v.Narozhnyy S.A.Klimin E.A.popova G.Dhalenne Institute of Spectroscopy Russian Academy of Sciences 5 Fizicheskaya Str. Troitsk Moscow region 142190 Russia Moscow State Institute of Electronics and Mathematics 109028 Moscow Russia Laboratoire de Physico-Chimie de l'état Solide Université Paris-Sud F-91405 Orsay France

Absorption spectra of the mixed chain nickelates （（NdxY1-x）2BaNiO5 were measured for different x. Experimentally two evidences for the presence of non-equivalent rare-earth centers （NEREC） were found. First, the linewidths show a very strong broadening for x when the calculated distribution over NEREC is wide. Second, a compficated lineshape of the lowest-frequency line in the region of the 4I9/2→4I1/2 electronic lransition is in good agreement with statistics of NEREC. A simple modeling for the line broadening due to NEREC is suggested.

关键词： Haldane chains non-equivalent rare-earth centers Fourier-lransform spectroscopy

Experimental study of coal fracture dynamics under the influence of cyclic freezing-thawing using shear elastic waves

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International Journal of Coal Science & Technology 2021年第4期8卷 562-574页

作者： Petr v.Nikolenko Svetlana A.Epshtein vladimir L.Shkuratnik polina S.Anufrenkova polina Scientific and Training Testing Laboratory of Physics and Chemistry of Coals National University of Science and Technology MISiSMoscowRussian Federation 119049 S.Anufrenkova1

Cyclic freezing-thawing can lead to fracture development in coal,affecting its mechanical and consumer *** study crack formations in coal,an ultrasonic sounding method using shear polarized waves was *** of three coal types(anthracite,lignite and hard coal)were *** research results show that,in contrast to the shear wave velocity,the shear wave amplitude is extremely sensitive to the formation of new cracks at the early stages of cyclic *** also show an inverse correlation between coal compressive strength and its tendency to form cracks under temperature impacts;shear wave attenuation increases more sharply in high-rank coals after the first freezing *** analysis of the received signals also confirmed significant crack formation in anthracite after the first freeze-thaw *** initial anisotropy was determined,and its decrease with an increase in the number of freeze-thaw cycles was *** data obtained forms an experimental basis for the development of new approaches to preserve coal consumer properties during storage and transportation under severe natural and climatic conditions.

关键词： Coal Cyclic freezing-thawing Ultrasonic Shear wave Fracture dynamics

Crop wild relatives of Kazakhstani Tien Shan:Flora,vegetation,resources

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Plant Diversity 2020年第1期42卷 19-32页

作者： Gulnara T.Sitpayeva Gulmira M.Kudabayeva Liliya A.Dimeyeva Nadezhda G.Gemejiyeva polina v.vesselova Institute of Botany and Phytointroduction Ministry of Education and Science050040AlmatyKazakhstan

This paper presents the results of the field study on species composition,geographical distribution,phytocoenotic diversity and resources of crop wild relatives(CWR) in Kazakhstan’s ranges of the Tien Shan *** of not only cultivated genera of crops are taken into account,but also a wider range of species of high socio-economic importance,including medicinal,fodder,essential oil and other *** of CWR includes 289 species belonging to 39 families and 145 *** them,9 species listed in the Red Data book of Kazakhstan:Pistacia vera,Rheum wittrockii,Armeniaca vulgaris,Malus sieversii,Allium pskemense,Allochrusa gypsophilloides,Sorbus sibirica,vitis vinifera and Artemisia *** highest plant diversity is recorded in intermountain plains and river valleys where meadow vegetation forms a high abundance of forage and resource *** diversity of wild fruit plants is concentrated in gallery *** of cereals are confined to dry steppe slopes in low piedmont *** populations of almond,pistachio,plum and cherry were recorded at dry slopes of low mountain *** estimation of the raw material base for 13 resource plants is *** Rumex tianschanicus,Berberis sphaerocarpa are recommended for industrial harvesting;for local pharmacy chain-Mentha longifolia,Origanum vulgare,*** ***,Ziziphora clinopodioides,Hypericum scabrum,Hypericum perforatum,and five Rosa species.

关键词： Crop wild relatives Flora vegetation Resources Mountains Kazakhstani Tien Shan

Influence of 10-(6-plastoquinonyl) decyltriphenylphosphonium on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced hyperglycemia

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World Journal of Diabetes 2019年第12期10卷 546-559页

作者： Aleksander A Agarkov Tatyana N popova Yana G Boltysheva Department of Medical Biochemistry and Microbiology Voronezh State University

BACKGROUND It is known that under conditions of tissue tolerance to insulin,observed during type 2 diabetes mellitus(DM2),there is an increased production of reactive oxygen ***,the free radicals can initiate lipid peroxidation(LPO)in lipoprotein *** concentration of LPO products can influence the state of insulin receptors,repressing their hormone connection activity,which is expressed as a reduction of the glucose consumption by *** is possible that reduction in glucose concentration during administration of 10-(6-plastoquinonyl)decyltriphenylphosphonium(SkQ1)to rats with DM2 may be related to the antioxidant properties of this *** To establish the influence of SkQ1 on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced *** To induce hyperglycemia,rats were fed a high-fat diet for 1 mo and then administered two intra-abdominal injections of streptozotocin with a 7-d interval at a 30 mg/kg of animal weight dose with citrate buffer equal to pH ***1 solution was administered intraperitoneally at a 1250 nmol/kg dose per *** samples were taken from control animals,animals with experimental hyperglycemia,rats with streptozotocin-induced glycemia that were administered SkQ1 solution,animals housed under standard vivarium conditions that were administered SkQ1,rats that were administered intraperitoneally citrate buffer equal to pH 4.4 once a week during 2 wk after 1-mo high-fat diet,and animals that were administered intraperitoneally with appropriate amount of solution without SkQ1(98%ethanol diluted eight times with normal saline solution).To determine the intensity of free radical oxidation and total antioxidant activity,we used the biochemiluminescence *** hydratase(AH),superoxide dismutase,and catalase activities were estimated using the Hitachi U-1900 spectrophotometer supplied with *** amount of citrate was determined by means of the Natel

关键词： Diabetes mellitus Free radical oxidation Antioxidants 10-(6-plastoquinonyl)decyltriphenylphosphonium