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Pseudogamous Apomixis in Maize and Sorghum in Diploid-Tetraploid Crosses

Phyton-International Journal of Experimental Botany 2019年第4期88卷 389-401页

作者： Marina Tsvetova lev Elkonin Yulia Italianskaya Agricultural Research Institute of South-East Region Department of BiotechnologySaratov410010Russia

Apomictic seed development is a complex process including formation of unreduced embryo sac,parthenogenetic embryo development from the egg cell,and endosperm formation either autonomously,or due to fertilization of polar nuclei by the sperm(under pseudogamous form of apomixis).In the latter case,an obstacle to the normal endosperm development is disturbance of maternal(m)-to-paternal(p)genomic ratio 2m:1p that occurs in the cases of pollination of unreduced embryo sac with haploid *** of tetraploid pollinators can overcome this problem because in such crosses maternal-to-paternal genomic ratio is 4m:2p that provides formation of kernels with plump *** tetraploid lines as pollen parents we observed formation of plump kernels on the ears and panicles of diploid maize and sorghum *** kernels had hybrid endosperm and diploid maternal-type embryo or hybrid embryo with different ploidy level(2n,3n,4n).The frequencies of plump kernels on the ear ranged from 0.2-0.3%to 5.7-6.2%counting from the number of ***-type plants were found in two maize lines,their frequency varying from 10.7 to 37.5%of the progeny *** CMS-lines of sorghum pollinated with tetraploid sorghum accessions,the frequency of plump kernels ranged from 0.6 to 14.0%counting from the number of ovaries;the frequency of maternal-type plants varied from 33.0 up to 96.1%.The hybrid nature of endosperm of the kernels that gave rise to maternal-type plants has been proved by marker gene expression and by SDS-electrophoresis of endosperm *** data testify to variable modes of seed formation under diploid×tetraploid crosses in maize and sorghum both by amphi-and by ***,usage of tetraploid pollinators might be a promising approach for isolation of apomixis in maize and sorghum accessions.

关键词： Interploidy crosses genomic balance unreduced embryo sac pseudogamous apomixis Zea mays L Sorghum bicolor(L.)Moench

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Localized States of an Excess Electron in an Ionic Cluster

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Communications in Theoretical Physics 2013年第12期60卷 738-746页

作者： K.V.Grigorishin B.I.lev Boholyubov Institute for Theoretical Physics of the National Academy of Sciences of Ukraine

A theory of an electron affinity for an ionic cluster is proposed both in a quasiclassical approach and with quantization of a polarization electric field in a nanopartiele. A critical size of the cluster regarding in formation of an electron＇s autolocalized state, dependencies of energy and radius of a polaron on a cluster＇s size are obtained by a variational method. It has been found that binding energy of the electron in the cluster depends on a eluster＇s radius but a radius of electron＇s auto-localization does not depend on the cluster＇s radius and it equals to the polaron radius in a corresponding infinity crystal. A bound state of the electron in a cluster is possible only if the duster＇s radius is more than the polaron radius.

关键词： cluster polaron autolocalization phonon comfinement

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Off-label use of targeted therapies in oncology

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World Journal of Clinical Oncology 2016年第2期7卷 253-257页

作者： Dominique levêque Dominique levêque Division of Pharmacyhôpital Hautepierre67000 StrasbourgFrance

Off-label use is defined by the prescription of a marketed drug outside the conditions described in the summary of product *** oncology,off-label prescribing of targeted therapies may occur in patients with other tumor types expressing the same *** associated to phenotypic approaches such as therapies against the tumoral vasculature(anti-angiogenic drugs) and new immunotherapies(checkpoint inhibitors) also carry the potential of alternative indications or ***-label use of targeted therapies is little documented and appears to be in the same range than that regarding older drugs with wide variations among *** compared with older agents,off-label use of targeted therapies is probably more rational through tumoral genotyping but is faced with a limited clinical support,reimbursement challenges related to the very high pricing and the cost of genotyping or molecular profiling,when applicable.

关键词： Targeted therapy Monoclonal antibody Off-label anticancer drug use Reimbursement Enzyme inhibitor

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Cold Nuclear Fusion in the Unitary Quantum Theory

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Chinese journal of nuclear physics 1995年第4期17卷 360-370页

作者： lev G.Sapogin Igor V.Kulikov Depariment of Physics MADI-Technical UniversilyMoscowRussia Langenfeldgasse 68/24/18 A-1120 ViennaAustria

The interaction of the charged particles in the new Unitary Quantum theory isconsidered. It is shown that the distance of approachment of deuterons to each other verystrongly depends on the phase of the wave function and not only upon the energy. This thesis isnot discussed in the conventional quantum theory. It can easily explain the experiments on thecold nuclear fusion.

关键词： Cold nuclear fusion Unitary quantum theory Non-linear or nonlocal theories and models Nuclear reaction and scattering models

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Effect of drought stress on male fertility restoration in A3 CMS-inducing cytoplasm of sorghum

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The Crop Journal 2017年第4期5卷 282-289页

作者： Valentin V.Kozhemyakin lev A.Elkonin Jeffery A.Dahlberg Department of Biotechnology Agricultural Research Institute of South-East Region Tulaikov Street 7 Saratov 410010 Russia Kearney Agricultural Research & Extension (KARE) 9240 South Riverbend Avenue Parlier CA 93648 USA

Use of cytoplasmic male sterility (CMS) in hybrid breeding requires effective male fertility-restoring lines. In sorghum, very few restoring lines that can restore fertility in A_3 CMS have been reported. To identify the reasons for this deficiency, F_1 and F_2 hybrids of an A_3 CMS line crossed with the line IS1112C, a donor of fertility-restoring (Rf) genes for A_3 cytoplasm, and testcrosses of fertile plants to A_3CMS lines were grown under contrasting water availability regimes in dryland and irrigated field plots. In the irrigated plots the frequency of fertile plants in testcrosses was twice that in dryland plots (P < 0.05). Fertile plants from the F_2 family grown in the irrigated plots showed significantly higher restoration ability than fertile plants from the same family grown in dryland plots. F_3 plants from the F_2 family grown in irrigated plots yielded on average a sixfold higherfrequency of fertile plants in testcrosses than F_3 plants derived from dryland plots (P < 0.01).Fertility of testcross hybrids correlated negatively with air vapor pressure deficit (VPD) at flowering (r = - 0.96; P < 0.01) suggesting that VPD is a trigger for downregulation of Rf genes for A_3 cytoplasm.

关键词： Sorghum bicolor (L.) Moench Cytoplasmic male sterility A3 cytoplasm Fertility-restoring genes Epigenetics Vapor pressure deficit

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Degassing of primordial hydrogen and helium as the major energy source for internal terrestrial processes

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Geoscience Frontiers 2012年第6期3卷 911-921页

作者： Arie lev Gilat Alexander Vol Geological Survey of Israel(Ret.) 6/2 Shoshan Tsahor St..Modi'in 71705.Israel Oshadi Drug Administration Ltd P.O.Box 2042.Rehovot 76120Israel

Examples of the mightiest energy releases by great earthquakes and volcanic eruptions and hypotheses providing explanations for them are analyzed along with the results of some recently pub- lished researches and visualizations. The emerging conclusions are that the mechanism of the strong earthquake is a chemical explosion; that volcanic eruption is a special type of earthquake wherein the hypocenter rises to the earth-surface; and that there is an association between the seismic-volcanic processes and mantle ＂fluids＂ and the lack of energy for mantle plumes. A conceptual system of hypoth- eses is put forward to explain the conservation of energy during Earth＇s accretion, its quasi-stable release by primordial H- and He-degassing and of the crucial role of the energy of degassing-eomprising- reactions in endogenic processes. Specific mechanisms and chemical processes are proposed for the gas-liquid mantle plumes melting through the solid mantle using heat-energy released in reactions of their metamorphic and chemical transformation under gradual decrease of pressure and temperature; volcanic gases are put forward as energy carriers. 3He performance as a unique measuring transformer correlative to the internal heat flow was used for calculation of energy release by degassing; it equals to 5.12 × 1020 J/yr, an amount of energy five-fold greater than the entire energy loss involved in earthquake and volcanic activity. The hypotheses proposed are objectively testable.

关键词： Earthquakes Volcanism Energy-source Hydrogen Helium Degassing

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Application of biostimulants for vegetative propagation of endangered Abies gracilis

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Journal of Forestry Research 2020年第4期31卷 1195-1199页

作者： lev P.Trofimuk Pavel S.Kirillov Aleksandr A.Egorov St.Petersburg State Forest Technical University Institutskii pereulok 5Saint-PetersburgRussia 194021 St.Petersburg State University University quay 7-9Saint-PetersburgRussia 199034

Abies gracilis Kom.(Pinaceae)is one of the rarest and endangered conifers in the Russian flora,which must be cultivated ex situ to ensure its *** of *** do not take root without *** used a selection of biostimulants,concentrations,and conditions of their use to significantly increase Abies gracilis rooting,and to accelerate the production of planting material,and to reduce rooting time to one *** tested 4 rooting systems:IBA,IBA with glucose and glycine,and original biostimulants(S-try and S-5).The original S-5 biostimulating system had the most balanced ratio of *** number of rooted samples increased 2.7 times and the length of roots increased 1.8 time when using S-5 as compared to IBA.S-try and S-5-original biostimulant systems were synthesized and collected in 2011 and 2014,respectively,and were tested in *** Forest Technical University.

关键词： Root formation Abies gracilis Biostimulant Planting Vegetative reproduction

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Deep Forest as a framework for a new class of machine-learning models

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National Science Review 2019年第2期6卷 186-187页

作者： lev V.Utkin Anna A.Meldo Andrei V.Konstantinov Laboratory of Neural Network Technology and Artificial Intelligence Peter the Great St. Petersburg Polytechnic University

A new deep learning framework—the socalled Deep Forest (DF), proposed by Zhi-Hua Zhou and Ji Feng [1,2]—can be regarded as one of the important events of 2017 in machine learning, although it was unjustly unnoticed by a large number of researchers. The DF combines several ensemble-based methods, including Random Forests (RFs) and Stacking, into a structure that is similar to a multi-layer neural network, but each layer in the DF

关键词： Deep Forest as a framework for a new class of machine-learning models

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Evaluation of embankment foundation creep in conditions of deep bedding of roof in permafrost soils

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Research in Cold and Arid Regions 2013年第5期5卷 534-539页

作者： Evgeny Ashpiz lev Khrustalev Department of Track and Track Facilities Moscow State University of Railway Department of Geology Lenynskie goryLomonosow Moscow State University

Railroad operating experience in permafrost conditions has shown that deformations of embankments on thawing foun- dations last for a long time. After an initial period of heat settlement due to permafrost degradation, the determining factor is the plastic flow of seasonal thawed soils of the foundation upper layer under the embankment. This paper provides a method to evaluate these deformations, and calculation examples using data from line sections of the Chum-Labytnangi Railway in northwestern Russia. It also discusses several methods of embankment stabilization, including the use of ver- tical thermosiphons.

关键词： permafrost railway plastic flow embankment stabilization methods thermosiphons

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Spinescent patterns in the flora of Jiaozi Snow Mountain,Southwestern China

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Plant Diversity 2020年第2期42卷 83-91页

作者： Qi Xu Simcha lev-Yadun Lu Sun Zhe Chen Bo Song Hang Sun Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming.650201YunnanChina University of Chinese Academy of Sciences Beijing100049China Department of Biology&Environment Faculty of Natural SciencesUniversity of Haifa-OranimTivon36006Israel

Spinescence has been thought to have evolved mainly as a defense against ***,studying its evolution in a whole flora is an excellent approach for understanding long-term plant-herbivore *** this study,we characterized the spinescent plant species of Jiaozi Snow Mountain,Southwestern China,in order to explore the effects of life forms,plant organs,phylogenetic position,and phytogeographical origin on spinescence *** Jiaozi Snow Mountain flora includes 137 spinescent species(9.2%)out of 1488 angiosperm *** found that in these spinescent species,vegetative organs(70.0%)were significantly more defended than reproductive organs(43.8%).Life form had a significant effect on spinescence *** species(18.6%)were more likely to be spiny than non-woody species(6.4%);moreover,woody species mostly defend their vegetative organs(92.2%),whereas herbaceous species mostly defend their reproductive organs(73.3%).For woody plants,leaf habit has a significant effect on ***,spinescence was more common on the reproductive organs of deciduous woody species than on those of evergreen woody species;furthermo re,spinescence was more common on the leaf blades of evergreens than on those of deciduous species;however,the proportion of spinescent petioles in deciduous species was significantly higher than in *** most common spine color was yellow(40.8%),followed by white(16.8%),red(15.8%),and brown(14.3%);furthermore,74.4%of spinescence that showed aposematic color was a different color than the plant organ on which *** findings suggest that spinescence is visually aposematic in the Jiaozi Snow Mountain ***,more families tended to have spines on vegetative organs(83.3%in vegetative organs,50.0%in reproductive organs),but the phylogenetic signals were *** proportion of spinescence was not significantly different between tropical(9.8%of genera,7.6%of species)and temperate(13.2%of ge

关键词： Herbivory Life form Physical defense Trade-off Plant apparency Spinescence

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