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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

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

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

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

Applications of two electric arc plasma torches for the beneficiation of natural quartz

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 267-273页

作者： Yuri-Mikhailovich Grishin Long Miao lev-Alekseevich Borisov Nikolay-Mikhailovich Serykh Alexey-Yurievich Kulagin Department of Thermal physics Bauman Moscow State Technical University Federal State Unitary Enterprise Tsentrkvarts

Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.

关键词： low-temperature plasma beneficiation high purity quartz arc plasma torch IOTA-STD standard

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

Onsite strength determination for early-opening decision making of high early strength concrete pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 291-303页

作者： Katelyn Kosar Lucio Salles de Salles Naser Pourakbar Sharifi Julie Vandenbossche lev Khazanovich Department of Civil and Environmental Engineering University of PittsburghPittsburghPA 15261USA Department of Civil Engineering Technology Environmental Management and SafetyRochester Institute of TechnologyRochesterNY 14623USA

High early strength(HES)concrete pavements are commonly opened to traffic within the first 24 h after construction,making early-opening decisions critical for pavement quality and traffic ***,most state departments of transportation rely on compressive strength testing for early-opening decision ***,there laboratory tests are labor intensive,costly and not always representative of field strength *** this study,non-destructive testing(maturity and ultrasonic tomography)was explored for faster and reliable in-situ strength *** experimental section constructed using HES concrete was routinely monitored using compressive testing,maturity,and ultrasonic tomography in the first 24 h after *** shear wave velocity,measured using ultrasonic tomography,was able to capture the strength-gain variability within a single slab and between different slabs due to the ability to monitor several locations in a short period of *** results were consistently conservative in the first 24 h of *** show that both maturity testing and ultrasonic tomography are able to replace or add to conventional strength testing for HES concrete pavements to facilitate making the opening decision within the first 24 *** tomography proved more beneficial as a result of the device's portability,increased speed of testing,and accurate estimations of HES concrete strength for the entire pavement length.

关键词： Road engineering High early strength concrete pavement Traffic early-opening Strength Maturity Ultrasonic tomography

Isolation, characterization and culture of Thy1-positive cells from fetal rat livers

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World Journal of Gastroenterology 2006年第24期12卷 3841-3847页

作者： Zvibel Isabel Bronstein Miri Hubel Einav Bar-lev Ella Halpern Zamir Oren Ran Liver Unit Gastroenterology Institute Tel Aviv Sourasky Medical CenterWeizmann 6Tel Aviv 64239Israel Internal Medicine Ⅰ Tel Aviv Sourasky Medical Center Weizmann 6Tel Aviv 64239Israel

AIM： To investigate whether Thyl recognizes oval cells in the fetal liver and to characterize the cultured Thy1 selected cells from E14 rat livers. METHODS： Thyl populations were analyzed by fluorescence activated cell sorter analysis. Thyl positive cells were isolated using magnetic beads. Hepatic markers were detected by Western blotting, immunocytochemistry and RT-PCR. RESULTS： The percentage of Thyl-positive cells decreased during early development of fetal rat liver （E13-E16）. E14 fetal livers contained 7.8% Thy1 positive cells, of which 61% were positive for α-fetoprotein （AFP） and 25% expressed albumin. The Thy1＋ population expressed oval cell markers c-Kit and CXCR4, liver enriched-transcription factors HNF1α and HNF6, hepatocytic markers albumin, AFP and cytokeratin 18, and biliary marker cytokeratin 19. Thy1- selected cells formed only mesenchymal colonies when plated on collagen and in serum-containing media. Thyl selected cells were able to form hepatic colonies positive for HNF1α, HNF6, albumin, AFP, cytokeratin 18, cytokeratin 19 and glycogen, when grown on STO feeder layers in serum free-media. CONCLUSION： Oval cells positive for Thyl are present in early liver embryonic stages.

关键词： Fetal liver Oval cells Thy1

Clustering of Pathogen-Response Genes in the Genome of Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第10期53卷 824-834页

作者： Olga A.Postnikova Natalia Y.Minakova Alexander M.Boutanaev lev G.Nemchinov United States Department of Agriculture Agricultural Research ServicePlant Sciences InstituteMolecular Plant Pathology Laboratory Institute of Basic Biological Problems Russian Academy of Sciences

Previously, we used heterologous expressed sequence tag （EST） mapping to generate a profile of 4 935 pathogen-response genes of Arabidopsis thaliana. In this work, we performed a computer analysis of this profile, revealing 1594 non-homologous clustered genes distributed among all A. thafiana chromosomes, whose co-regulation may be related to host responses to pathogens. To supplement computer data, we arbitrarily selected two clusters and analyzed their expression levels in A. thaliana ecotypes Col-0 and C24 during infection with the yellow strain of Cucumber mosaic virus CMV（Y）. Ecotype Col-0 is susceptible to CMV（Y）, whereas C24 contains the dominant resistance gene RCY1. Upon infection with CMV（Y）, all clustered genes were significantly activated in the resistant ecotype C24. In addition, we demonstrated that posttranslational histone modifications associated with trimethylation of histone H3 lysine 27 are most likely involved in regulation of several cluster genes described in this study. Overall, our experiments indicated that pathogen-response genes in the genome of A. thaliana may be clustered and co-regulated.

关键词： CMV H3K27me3 heterologous EST mapping clustering of defense-related genes.