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Late Jurassic ammonite evolution and paleoenvironment of the russian Platform

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Science China Earth sciences 2009年第12期52卷 2024-2028页

作者： MITTA Vasily Paleontological Institute Russian Academy of Sciences Moscow 117997 Russia

The stratigraphic record shows a considerable decrease in ammonoid taxonomic diversity and distinct changes of ammonite shell morphology toward end of the Jurassic in the Central russian Basin. By the end-Volgian, ammonites were represented by only two genera, belonging to a single family Craspeditidae, which differ markedly from previous ammonite families in their shell form. The end-Jurassic decrease in ammonoid biodiversity started in the mid-Volgian and is mainly correlated with shallowing of the shelf.

关键词： Volgian Ryazanian ammonites biodiversity russian Platform

SERS-based lateral flow immunoassay of troponin I by using gapenhanced Raman tags

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Nano Research 2019年第2期12卷 413-420页

作者： Boris N. Khlebtsov Daniil N. Bratashov Nadezhda A. Byzova Boris B. Dzantiev Nikolai G. Khlebtsov Institute of Biochemistry and Physiology of Plants and Microorganisms Russian Academy of Sciences Saratov 410049 Russia Saratov State University Saratov 410012 Russia A. N. Bach Institute of Biochemistry Research Centre of Biotechnology Russian Academy of Sciences Moscow 119071 Russia

The lateral flow immuno assay (LFIA) has emerged as a powerful tool for rapid scree ning owing to its simplicity and flexibility for detection of various biomarkers. However, conventional LFIA strips have several disadvantages, including limits in quantitative analysis and low sensitivity. Here we developed a novel surface-e nhanced Rama n scatteri ng LFIA based on non spherical gap-e nhanced Raman tags (GERTs), with Raman molecules (RMs) embedded in a 1-nm gap between Au nanorod core and Au shell. Such tags have a strong and uniform surface-enhanced Rama n scattering (SERS) resp on se, an order of mag nitude higher than that of other comm on SERS tags such as Au nano rods, nano stars, Au nano shells with surface-adsorbed RMs, or spherical GERTs with embedded RMs. The feasibility of the tags was dem on strated by the semiqua ntitative and sen sitive detecti on of the heart disease biomarker cardiac tropo nin I (cTnI). GERTs were conjugated with mono clonal antibodies and used for LFIA in the same way as ordinary functionalized colloidal gold. The presenee of the target antigen, cTnI, was identified by Raman microscopy mapping of the test zone. With the SERS-based LFIA, the limit of cTnI detection was about 0.1 ng/mL. This value is within the diagnostic range of cTnI in the blood serum of patients with heart infarction and is 30 times lower than that of the colorimetric LFIA test using the same antibodies and either GERTs or colloidal gold as labels.

关键词： surface-enhanced Raman scattering (SERS) lateral flow immunoassay Au core/shell nanorods gap-enhanced Raman tags cardiac troponin I

Highly transparent ytterbium doped yttrium lanthanum oxide ceramics

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Journal of Rare Earths 2014年第3期32卷 254-258页

作者： M.Ivanov Yu.Kopylov V.Kravchenko 李江 A.Medvedev 潘裕柏 Institute of Electrophysics UrB of RAS 106Amundsena 620016 Ekaterinburg Russia Institute of Radioengineering and Electronics named after V.A. Kotelnikov RAS Vvedensky Sq. 1 Fryazino Moscow region 141120 Russia Shanghai Institute of Ceramics Chinese Academy of Science Ural Federal University 19 Mira 620002 Ekaterinburg Russia

To prepare ytterbium doped lanthania yttria nanopowder a method of laser evaporation of mixed oxides was used. After calcinations of the powder at 1200 ℃ a pure single-phase solid solution yb3＋：（LaxY1-x）2O3 was formed in the nanoparticles. Influence of lanthanum oxide as an isovalent additive on the yttria structure was investigated. The lanthanium ions were proved to be a good aid to sinter yttria ceramics doped with Yb3＋ at moderate temperatures about 1650 ℃. The ceramics with relative density higher than 99.99% and grain size about 40 μm were fabricated. Full transmittance of 1.8 mm thick Yb0.11 La0.23Y1.66O3 ceramics reached 82.5% at 800 nm. This material could be a good gain medium for ytterbium high power pulse lasers.

关键词： RE-doped ceramics nanopowders ytterbium oxide transparency

Expression of auxin synthesis gene tms1 under control of tuber-specific promoter enhances potato tuberization in vitro

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Journal of Integrative Plant Biology 2015年第9期57卷 734-744页

作者： Oksana O.Kolachevskaya Valeriya V.Alekseeva Lidiya I.Sergeeva Elena B.Rukavtsova Irina A.Getman Dick Vreugdenhil Yaroslav I.Buryanov Georgy A.Romanov Signaling Systems Laboratory Timiryazev Institute of Plant Physiology Russian Academy of Sciences Plant Biotechnology Laboratory Branch of Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Laboratory of Plant Physiology Wageningen University Department of Molecular Basis of Ontogenesis Belozersky Institute of Physico-Chemical Biology Moscow State University

Phytohormones, auxins in particular, play an important role in plant development and productivity. Earlier data showed positive impact of exogenous auxin on potato (Solanum tuberosum L.) tuberization. The aim of this study was to generate potato plants with increased auxin level predominantly in tubers. To this end, a pBinB33-tms1 vector was constructed harboring the Agrobacterium auxin biosynthesis gene tms1 fused to tuber-specific promoter of the class I patatin gene (B33-promoter) of potato. Among numerous independently generated B33:tms1 lines, those without visible differences from control were selected for detailed studies. In the majority of transgenic lines, tms1 gene transcription was detected, mostly in tubers rather than in shoots. Indoleacetic acid (IAA) content in tubers and the auxin tuber-to-shoot ratio were increased in tms1-expressing transformants. The organ-specific increase in auxin synthesis in B33:tms1-transformants accelerated and intensified the process of tuber formation, reduced the dose of carbohydrate supply required for in vitro tuberization, and decreased the photoperiodic dependence of tuber initiation. Overall, a positive correlation was observed between tms1 expression, IAA content in tubers, and stimulation of tuber formation. The revealed properties of B33:tms1 transformants imply an important role for auxin in potato tuberization and offer prospects to magnify potato productivity by a moderate organ-specific enhancement of auxin content.

关键词： Auxin gene expression Solanum tuberosum tms1 transgenic potato tuberization tuber yield

Microbial processes and factors controlling their activities in alkaline lakes of the Mongolian plateau

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1391-1401页

作者： Zorigto B.NAMSARAEV Svetlana V.ZAITSEVA Vladimir M.GORLENKO Ludmila P.KOZYREVA Bair B.NAMSARAEV National Research Centre "Kurchatov Institute" Akademika Kurchatova pl.1Moscow 123182Russia Winogradsky Institute of Microbiology RAS Prosp.60-let Oktyabrya 7/2Moscow 117312Russia Laboratory of Microbiology Institute of General and Experimental BiologySiberian branch RASSakhyanovoi St .6UlanUdeBuryat Republic 670047Russia Buryat State University Smolina21Ulan-UdeBuryat Republic 670000Russia

A striking feature of the Mongolian plateau is the wide range of air temperatures during a year, -30 to 30~C. High summer temperatures, atmospheric weathering and the arid climate lead to formation of numerous alkaline soda lakes that are covered by ice during 6-7 months per year. During the study period, the lakes had pH values between 8.1 to 10.4 and salinity between 1.8 and 360 g/L. According to chemical composition, the lakes belong to sodium carbonate, sodium chloride-carbonate and sodium sulfate-carbonate types. This paper presents the data on the water chemical composition, results of the determination of the rates of microbial processes in microbial mats and sediments in the lakes studied, and the results of a Principal Component Analysis of environmental variables and microbial activity data. Temperature was the most important factor that influenced both chemical composition and microbial activity, pH and salinity are also important factors for the microbial processes. Dark CO2 fixation is impacted mostly by salinity and the chemical composition of the lake water. Total photosynthesis and sulfate-reduction are impacted mostly by pH. Photosynthesis is the dominant process of primary production, but the highest rate （386 mg C/（L.d）） determined in the lakes studied were 2-3 times lower than in microbial mats of lakes located in tropical zones. This can be explained by the relatively short warm period that lasts only 3-4 months per year. The highest measured rate of dark CO2 assimilation （59.8 mg C/（L·d）） was much lower than photosynthesis. The highest rate of sulfate reduction was 60 mg S/（L·d）, while that of methanogenesis was 75.6 μL CH4/（L·d） in the alkaline lakes of Mongolian plateau. The rate of organic matter consumption during sulfate reduction was 3-4 orders of magnitude higher than that associated with methanogenesis.

关键词： alkaline lakes microbial mats Mongolian plateau biogeochemical cycles

Gold nanorods with a hematoporphyrin-loaded silica shell for dual-modality photodynamic and photothermal treatment of tumors in vivo

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Nano Research 2014年第3期7卷 325-337页

作者： Georgy Terentyuk Elizaveta Panfilova Vitaly Khanadeev Daniil Chumakov Elina Genina Alexey Bashkatov Valery Tuchin Alia Bucharskaya Galina Maslyakova Nikolai Khlebtsov Boris Khlebtsov Saratov State University 83 Astrakhanskaya Saratov 410012 Russia Institute of Biochemistry and Physiology of Plants and Microorganisms 13 pr. Entuziastov Saratov 410049 Russia Institute of Precise Mechanics and Control of RAS 24 Rabochaya Saratov 410028 Russia Ulyanovsk State University 42 Lev Tolstoy Ulyanovsk 432017 Russia Optoelectronics andMeasurement Techniques Laboratory UniversityofOulu P.O. Box4500 Oulu FIN-90014 Finland Saratov State Medical University 112 Bolshaya Kazachia Saratov 410012 Russia

Nanocomposites （NCs） consisting of a gold nanorod core and a mesoporous silica shell doped with hematoporphyrin （HP） have been fabricated in order to improve the efficiency of cancer treatment by combining photothermal and photodynamic therapies （PDT ＋ PTT） in vivo. In addition to the long-wavelength plasmon resonance near 810-830 nm, the fabricated NCs exhibited a 400-nm absorbance peak corresponding to bound HP, generated singlet oxygen under 633-nm excitation near the 632.5-nm Q-band, and produced heat under a 808-nm near-infrared （NIR） laser irradiation. These modalities were used for a combined PDT ＋ PTT treatment of large （about 3 cm3） solid tumors in vivo with a xenorafted tumor rat model. NCs were directly injected into tumors and irradiated simultaneously with 633-nm and 808-nm lasers to stimulate the combined photodynamic and photothermal activities of NCs. The efficiency of the combined therapy was evaluated by optical coherence tomography, histological analysis, and by measurements of the tumor volume growth during a 21-day period. The NC-mediated PDT led to weak changes in tissue histology and to a moderate 20% decrease in the tumor volume. In contrast, the combined PDT ＋ PTT treatment resulted in the large-area tumor necrosis and led to dramatic decrease in the tumor volume.

关键词： nanocomposites gold nanorods mesoporous silica hematoporphyrin photodynarnic andphotothermal therapy

Early Evolution of Apocrita (Insecta,Hymenoptera) as Indicated by New Findings in the Middle Jurassic of Daohugou,Northeast China

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 834-873页

作者： Alexandr P. RASNITSYN ZHANG Haichun Palaeontological Institute Russian Academy of Sciences 117997 Moscow Russia Natural History Museum London SW7 5BD UK State Key Laboratory of Palaeobiology and Stratigraphy （Nanjing Institute of Geology and Palaeontology the Chinese academy of sciences） Nanjing 210008 China

The classification and phylogeny of the basal Vespina （= Orussoidea ＋ Apocrita） are reconsidered based primarily on rich and well preserved material from the Middle Jurassic of Daohugou in Inner Mongolia, China. Comparatively smooth morphological transitions are traced from a Xiphydriidae-like ancestor toward Orussoidea via the Jurassic family Karatavitidae, and through Karatavitidae and the Jurassic and Early Cretaceous family Ephialtitidae independently to Stephanidae, to Evanioidea, and, via the extinct Jurassic Kuafuidae fam. nov. to the remaining Apocrita. New hypothesis is proposed concerning development of the characteristic wasp-waist of Apocrita, which is supposed to appear independently and in different ways in Evanioidea and in the rest of Apocrita. As a result, six infraorders are proposed for the suborder Vespina with the following taxonomic structure： infraorder Orussomorpha including the only superfamily Orussoidea （Karatavitidae ＋ Paroryssidae ＋ Orussidae）, infraorder Stephanomorpha with the only superfamily Stephanoidea （Ephialtitidae ＋ Stephanidae）, infraorder Evaniomorpha with the only superfamily Evanioidea of traditional composition, infraorder Ceraphronomorpha with the superfamih＇es Ceraphronoidea s. str. and monotypical Megalyroidea and Trigonaloidea, and the infraorders Proctotrupomorpha, Ichneumonomorpha, and Vespomorpha of traditional composition. The family Kuafuidae is unplaced to infraorder because it is putatively paraphyletic with respect to Ceraphronomorpha, Proctotrupomorpha, Ichneumonomorpha and Vespomorpha. Described as new are Karatavites junfengi sp. nov, Praeratavites wuhuaensis sp. nov., P. perspicuus sp. nov, Postxiphydria daohugouensis gen. et sp. nov., P. ningchengensis gen. et sp. nov., Postxiphydroides strenuus gen. et sp. nov., Praeratavitoides amabilis gen. et sp. nov., Proapocritus densipediculus sp. nov., P. sculptus sp. nov., P. longantennatus sp. nov., P. formosus sp. nov., P. atropus sp. nov., P. elegans sp. nov., S

关键词： Apocrita origin wasp-waist origin Evanioidea fossil Hymenoptera Middle Jurassic Daohugou

Seiberg-Witten theory as a complex version of Abelian Higgs model

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Science China Mathematics 2017年第6期60卷 1089-1100页

作者： SERGEEV Armen Steklov Mathematical Institute Moscow 100001 Russia

The adiabatic limit procedure associates with every solution of Abelian Higgs model in （2 ^- 1） dimensions a geodesic in the moduli space of static solutions. We show that the same procedure for Seiberg- Witten equations on 4-dimensional symplectic manifolds introduced by Taubes may be considered as a complex （2＋2）-dimensional version of the （2＋ 1）-dimensional picture. More precisely, the adiabatic limit procedure in the 4-dimensional case associates with a solution of Seiberg-Witten equations a pseudoholomorphic divisor which may be treated as a complex version of a geodesic in （2＋l）-dimensional case.

关键词： Ginzburg-Landau equations vortices Seiberg-Witten equations

Radio pulsars with expected gamma radiation and gamma-ray pulsars as pulsating radio emitters

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Research in Astronomy and Astrophysics 2018年第8期18卷 5-12页

作者： Igor Fedorovich Malov Maria Andreevna Timirkeeva Pushchino Radio Astronomy Observatory Astro Space Center P.N.Lebedev Physical Institute

Pulsars play a crucial astrophysical role as highly energetic compact radio, X-ray and gamma- ray sources. Our previous works show that radio pulsars identified as pulsing gamma-ray sources by the Large Area Telescope （LAT） on board the Fermi Gamma-Ray Space Telescope have high values of magnetic field near the light cylinder, two-three orders of magnitude stronger compared with the magnetic fields of radio pulsars： log Blc （G） are 3.60-3.95 and 1.75 correspondingly. Moreover, their losses of rotational energy are also three orders higher than the corresponding values for the main group of radio pulsars on average： logE（erg s-1） = 35.37-35.53 and 32.64. The correlation between gamma- ray luminosities and radio luminosities is found. It allows us to select those objects from all sets of known radio pulsars that can be detected as gamma-ray pulsars with high probability. We provide a list of such radio pulsars and propose to search for gamma emission from these objects. On the other hand, the known catalog of gamma-ray pulsars contains some sources which are not currently identified as radio pulsars. Some of them have large values of gamma-ray luminosities and according to the obtained correlation, we can expect marked radio emission from these objects. We give the list of such pulsars and expected flux densities to search for radiation at frequencies 1400 and 111 MHz.

关键词： pulsars individual - gamma-ray bursts individual - stars magnetic field