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Molecular Plant 2009年第4期2卷 700-710页

作者： olga Pontes Pedro Costa-Nunes Paul vithayathil Craig S. Pikaard Biology Department Washington University 1 Brookings Drive St Louis MO 63130 USA

In Arabidopsis, pericentromeric repeats, retroelements, and silenced rRNA genes are assembled into heterochromatin within nuclear structures known as chromocenters. The mechanisms governing higher-order heterochromatin organization are poorly understood but 24-nt small interfering RNAs （siRNAs） are known to play key roles in heterochromatin formation. Nuclear RNA polymerase Iv （Pol Iv）, RNA-DEPENDENT RNA POLYMERASE 2 （RDR2）, and DICER-LIKE 3 （DCL3） are required for biogenesis of 24-nt siRNAs that associate with ARGONAUTE 4 （AGO4）. Nuclear RNA polymerase v （Pol v） collaborates with DRD1 （DEFICIENT IN RNA-DEPENDENT DNA METHYLATION 1） to generate transcripts at heterochromatic loci that are hypothesized to bind to siRNA-AGO4 complexes and subsequently recruit the de-novo DNA methylation and/or histone modifying machinery. Here, we report that decondensation of the major pericentromeric repeats and depletion of the heterochromatic mark histone H3 lysine 9 dimethylation at chromocenters occurs specifically in pol v and drdl mutants. Disruption of pericentromeric repeats condensation is coincident with transcriptional reactivation of specific classes of pericentromeric 180-bp repeats. We further demonstrate that Pol v functions independently of Pol Iv, RDR2, and DCL3-mediated siRNA production to affect interphase heterochromatin organization, possibly by involving RNAs that recruit structural or chromatin-modifying proteins.

关键词： RNA polymerase v RNA-directed DNA methylation heterochromatin centromere gene expression.

Chemical geothermometry:application to mud volcanic waters of the Caucasus region

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Frontiers of Earth Science 2020年第4期14卷 738-757页

作者： olga E.Kikvadze vasilii Yu.Lavrushin Boris G.Polyak Geological Institute Russian Academy of SciencesMoscow119017Russia Siberian Branch of the RAS V.S.Sobolev Institute of Geology and MineralogyNovosibirsk630090Russia

The generation temperatures of gas-water fluids released from mud volcanoes in different provinces of the Caucasian region have been constrained using Mg/Li(T_(Mg/Li))chemical *** volcanic fluids in the Taman Peninsula(Kerch-Taman mud volcanic province)were generated at temperatures(T_(Mg/Li))from 41℃ to 137℃.The depths of the respective mud reservoirs estimated from T_(Mg/Li) values and local geothermal gradient are in a range of 1.0 to 3.4 km which spans the Maykop Formation of marine *** the South Caspian province,the T_(Mg/Li) values of waters vary from 18℃ to 137℃ and the respective root depths HMg/Li of mud volcanoes range from∼0.85 to 6.5 *** obtained T_(Mg/Li) values for the analyzed mud volcanic waters from Caucasian provinces are in positive correlation with HCO3^(−)contents and water oxygen isotope compositions(δ^(18)OH_(2)O andΔδ^(18)OH_(2)O)and in high negative correlation with Cl^(−).The increase of T_(Mg/Li) toward the Greater Caucasus Range,as well as the lateral T_(Mg/Li) patterns in the Taman and South Caspian mud volcanic provinces,support the idea that mud volcanic fluids generate at temperatures increasing progressively toward the Alpine orogenic belt.

关键词： mud volcano fluid chemical geothermometry stable isotopes Caucasus region

State Regulation of Agrarian Entrepreneurship in Russia and China over a Period of Crisis of 2008-2010

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State Regulation of Agrarian Entrepreneurship in Russia and ...

Synthesis,structure and magnetic properties of Sm_(1.2)Ho_(0.8)Fe_(17)Hx(X=0;4.4)

作者： olga v.Bartiuk Khabarovsk State Academy of Economics and Law 134 Tikhookeanskaya str.Khabarovsk680042

The article gives the definition of agrarian entrepreneurship,develops main tendencies of state anti-crisis activities in the field of regulation of Russian and Chinese agrarian entrepreneurs’activity over a period of *** article also gives the preliminary evaluation of effectiveness of agrarian entrepreneurship regulation implemented by the governments of both countries.

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Journal of Rare Earths 2021年第9期39卷 1089-1094页

作者： S.v.veselova M.A.Paukov I.S.Tereshina v.N.verbetsky K.v.Zakharov D.I.Gorbunov A.N.vasiPev Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Nuclear Fuel Cycle Department.Centrum vyzkumu Rez Hlavni 130Husinec-Rez 25068.Czech Republic Immanuel Kant Baltic Federal University Kaliningrad 236004Russia Faculty of Mathematics and Physics Charles UniversityPrague 12116Czech Republic Hochfeld-Magnetlabor Dresden(HLD-EMFL) Helmholtz-Zentrum Dresden-RossendorfDresden 07328Germany f National Research South Ural State UniversityChelyabinsk 454080Russia

Intermetallic compounds based on rare-earth metals and iron are by far the most promising materials for permanent mag *** this work,the multicomponent compound Sm_(1.2)Ho_(0.8)Fe_(17)was prepared by in duction *** hydride Sm_(1.2)Ho_(0.8)Fe_(17)H_(4.4)with a high hydrogen content was obtained by direct hydrogenation of the intermetallic *** rhombohedral Th2Zn17-type of structure(space group R3^(-)m)is inhere nt to parent compound and hydride as *** effect of hydrogenation on the magneric properties of Sm_(1.2)Ho_(0.8)Fe_(17)was *** temperature of the hydride Sm_(1.2)Ho_(0.8)-Fe_(17)H_(4.4)is higher than that of parent compound by△Tc=138 *** hydrogen embedded in Sm_(1.2)Ho_(0.8)Fe_(17)crystal lattice in creases the saturation magnetization(σs)at T=300 K,but does not significantly affect%at T=4.2 *** ferrimagnetic structure is retained in magnetic fields up to 58 T in the parent compound,while,in the hydride,there is a spin-reorie ntatio n phase transitio n observed at 55 *** is found that the parameter of the in tersublattice exchange interaction decreases significantly in the hydride Sm_(1.2)Ho_(0.8)Fe_(17)Hg_(4.4)(and in the nitride Sm_(1.2)Ho_(0.8)Fe_(17)N_(2.4))which is associated with boosting of the unit-cell volume and distances between magnetic ions.

关键词： Intermetallic compound Hydride Crystal structure Magnetization Magnetic phase transition Exchange interaction

Multispectral sensing of biological liquids with hollow-core microstructured optical fibres

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Light(Science & Applications) 2020年第1期9卷 346-357页

作者： Timur Ermatov Roman E.Noskov Andrey AMachnev Ivan Gnusov vsevolod Atkin Ekaterina N.Lazareva Sergei v.German Sergey S.Kosolobov Timofei S.Zatsepin olga v.Sergeeva Julia S.Skibina Pavel Ginzburg valery v.Tuchin Pavlos G.Lagoudakis Dmitry A.Gorin Skolkovo Institute of Science and Technology 3 Nobelya str.Moscow 121205Russia Department of Electrical Engineering Tel Aviv UniversityRamat AvivTel Aviv 69978Israel Light-Matter Interaction Centre Tel Aviv UniversityRamat AvivTel Aviv 69978Israel Saratov State University 83 Astrakhanskaya str.Saratov 410012Russia Tomsk State University 36 Lenin’s av.Tomsk 634050Russia M.v.Lomonosov Moscow State University Leninskie Gory1-3Moscow 119992Russia SPE LLC Nanostructured Glass Technology 10150 Let OktjabrjaSaratov 410033Russia Center for Photonics and 2D Materials Moscow Institute of Physics and TechnologyDolgoprudny 141700Russia Institute of Precision Mechanics and Control of the Russian Academy of Sciences 24 Rabochaya str.Saratov 410028Russia

The state of the art in optical biosensing is focused on reaching high sensitivity at a single wavelength by using any type of optical *** common strategy,however,disregards the promising possibility of simultaneous measurements of a bioanalyte’s refractive index over a broadband spectral ***,we address this issue by introducing the approach of in-fibre multispectral optical sensing(IMOS).The operating principle relies on detecting changes in the transmission of a hollow-core microstructured optical fibre when a bioanalyte is streamed through it via liquid *** offers a unique opportunity to measure the refractive index at 42 wavelengths,with a sensitivity up to ~3000 nm per refractive index unit(RIU)and a figure of merit reaching 99 RIU^(−1) in the visible and near-infra-red spectral *** apply this technique to determine the concentration and refractive index dispersion for bovine serum albumin and show that the accuracy meets clinical needs.

关键词： refractive spectral microstructure

Electrochemical performance of Klason lignin as a low-cost cathode-active material for primary lithium battery

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Journal of Energy Chemistry 2015年第3期24卷 346-352页

作者： Sergey v Gnedenkov Denis P Opra Ludmila A Zemnukhova Sergey L Sinebryukhov Iliya A Kedrinskii olga v Patrusheva valentin I Sergienko Institute of Chemistry Far Eastern BranchRussian Academy of Sciences Far Eastern Federal University Siberian State Technological University

A few classes of organic compounds are promising electrode-active materials due to their high power and energy densities,low cost,environmental friendliness,and *** the present work,the possibility of using Klason lignin extracted from buckwheat husks as a cathode-active material for a primary lithium battery has been investigated for the first *** reaction mechanism in the lithium/lignin electrochemical cell was suggested based on the deep galvanostatic discharge（up to 0.005 v） data and cyclic voltammetry *** dependence of the electrochemical behavior of the Klason lignin on the milling degree was *** maximum specific capacity of the lignin is equal to 600 m Ah g-1at a discharge current density of 75 μA *** effect of the thermal treatment of the Klason lignin cathode at250°C on the cell performance was *** was found that the discharge capacity of the cell increased by 30% in the range from 3.3 to0.9 v for the treated cathode *** results demonstrate the prospects of using Klason lignin-based electrochemical cells as low-rate primary power sources.

关键词： Klason lignin primary lithium battery organic electrode buckwheat husks

Azithromycin in a triple therapy for *** eradication in active duodenal ulcer

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World Journal of Gastroenterology 2002年第5期8卷 879-882页

作者： vladimir T.Ivashkin Tatiana L.Lapina Oksana Yu.Bondarenko olga A. Sklanskaya Petr va.Grigoriev Yuri v.vasiliev Emilia P.Yakovenko Pavel v.Gulyaev valeri I.Fedchenko v.vasilenko Clinic of internal diseases gastroenterology and hepatology of the Moscow Sechenov Medical Academy119881 Pogodinskaya 5MoscowRussia Pathology Department of the Moscow Sechenov Medical Academy 119881Trubetskaya 8MoscowRussia Gastroenterological Center of the Health Ministry of Russia 105203N.Pervomayskaya ul.70MoscowRussia Central Institution of Gastroenterology 111123Sh.Entusiastov 86MoscowRussia

AIM:To assess and compare the efficacy and safety of two triple regimes:A)metronidazole,amoxicillin and omeprazole, which is still widely used in Russia,and B)azithromycin, amoxicillin and omeprazole in healing active duodenal ulcer and *** eradication. METHODS:100 patients with active duodenal ulcer were included in the open,multicentre,randomized study with comparative *** were randomly assigned to one of the following one-week triple regimes:A) metronidazole 500 mg bid,amoxicillin I g bid and omeprazole 20 mg bid(OAM,n=50)and B)azithromycin 1 god for the first 3 days(total dose 3 g),amoxicillin 1 g bid and omeprazole 20 mg bid(OAA,n=50).Omeprazole 20 mg od was given after the eradication course as a monotherapy for three *** control endoscopy was performed 8 weeks after the *** was determined in the entry of the study and four weeks after the cessation of treatment by means of histology and CLO-test. RESULTS:97 patients completed the study according to the protocol(1 patient of the OAM group did not come to the control endoscopy,2 patients of the OAA group stopped the treatment because of mild allergic urticaria).Duodenal ulcers were healed in 48 patients of the OAM group(96 %, C190.5-100 %)and in 46 patients of the OAA group(92 %, CI 89.5-94.5 %)(p=ns).*** was eradicated in 15 out of 50 patients with OAM(30 %,CI 17-43 %)and in 36 out of 50 patients treated with OAA(72 %;CI 59-85 %) (Pvc\ the majority of patients, which is an essential argument to withdraw this regimen out of the national recommendations. Macrolide with amoxicillin are preferable to achieve higher eradication rates. Azithromycin (1 g od for the first 3 days) can be considered as a successful component of the triple PPI-based regimen.

关键词： Helicobacter pylori Adolescent Adult Aged Amoxicillin dosage Anti-Bacterial Agents Anti-Ulcer Agents Azithromycin Comparative Study Drug Therapy, Combination Duodenal Ulcer Female Helicobacter Infections Humans Male Metronidazole Middle Aged Omeprazole Penicillins Research Support, Non-U.S. Gov't Treatment Outcome

Diatomic Gaseous Sulfur Obtained at Low Temperature Catalytic Decomposition of Hydrogen Sulfide

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Journal of Chemistry and Chemical Engineering 2013年第11期7卷 1007-1013页

作者： Anatoliy N. Startsev olga v. Kruglyakova Boreskov Institute of Catalysis Novosibirsk 630099 Russia

Experimental evidences of occurrence of gaseous diatomic sulfur produced in the low temperature catalytic decomposition of hydrogen sulfide 2 H2S ←→ 2 H2 ＋ S2 （g） are summarized. The S2 molecule is suggested to be in the ground triplet state. Analysis of literature data allows concluding that the S2 metastable singlet state is realized in the thermal dissociation of hydrogen sulfide and solid sulfur. Arguments in favor of the hypothesis are been discussed.

关键词： Diatomic gaseous sulfur H2S decomposition sulfur electronic structure reaction thermodynamics standard enthalpyformation.

Aberrant expression of alternative isoforms of transcription factors in hepatocellular carcinoma

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World Journal of Hepatology 2018年第10期10卷 645-661页

作者： olga Krivtsova Anna Makarova Natalia Lazarevich Federal State Budgetary Institution “N.N.Blokhin Medical Research Center of Oncology”of the Ministry of Health of the Russian FederationMoscow 115478Russian M.v.Lomonosov Moscow State University Moscow 119991Russian

Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs) observed in HCC leads to profound changes in the hepatic transcriptional program that facilitates tumor progression. In addition, recent reports suggest that substantial aberrations in the production of TF isoforms occur in HCC. In vitro experiments have identified distinct isoform-specific regulatory functions and related biological effects of liver-specific TFs that are implicated in carcinogenesis, which may be relevant for tumor progression and clinical outcome. This study reviews available data on the expression of isoforms of liver-specific and ubiquitous TFs in the liver and HCC and their effects, including HNF4α, C/EBPs, p73 and TCF7 L2, and indicates that assessment of the ratio of isoforms and targeting specific TF variants may be beneficial for the prognosis and treatment of HCC.

关键词： Alternative isoforms Transcription factors Hepatocellular carcinoma Alternative splicing Hepatic differentiation Personalized treatment

Pulse generation with ultra-superluminal pulse propagation in semiconductor heterostructures by superradiant-phase transition enhanced by transient coherent population gratings

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Light(Science & Applications) 2016年第1期5卷 737-743页

作者： Peter P vasil’ev Richard v Penty Ian H White Centre for Photonic Systems Department of EngineeringUniversity of CambridgeCambridge CB30FAUK Quantum Electronics Division PN Lebedev Physical InstituteMoscow 119991Russia

This paper reports the observation of ultra-superluminal pulse propagation in multiple-contact semiconductor heterostructures in a superradiant emission regime,and shows definitively that it is a different class of emission from conventional spontaneous or stimulated *** population gratings induced in the semiconductor medium under strong electrical pumping have been shown to cause a major decrease of the group refractive index,in the range of 5–40%.This decrease is much greater than that caused by conventional carrier depletion or chirp *** decrease in refractive index in turn causes faster-than-c propagation of femtosecond *** measurement also proves the existence of coherent amplification of electromagnetic pulses in semiconductors at room temperature,the coherence being strongly enhanced by interactions of the light with coherent transient gratings locked to carrier *** pulse-generation technique is anticipated to have great potential in applications where highly coherent femtosecond optical pulses must be generated on demand.

关键词： phase transition population grating superradiance superluminal propagation