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npj Computational Materials 2021年第1期7卷 909-916页

作者： Ayana Ghosh Bobby G.Sumpter Ondrej Dyck sergei V.Kalinin Maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA

Deep learning has emerged as a technique of choice for rapid feature extraction across imaging disciplines,allowing rapid conversion of the data streams to spatial or spatiotemporal arrays of features of ***,applications of deep learning in experimental domains are often limited by the out-of-distribution drift between the experiments,where the network trained for one set of imaging conditions becomes sub-optimal for different *** limitation is particularly stringent in the quest to have an automated experiment setting,where retraining or transfer learning becomes impractical due to the need for human intervention and associated *** we explore the reproducibility of deep learning for feature extraction in atom-resolved electron microscopy and introduce workflows based on ensemble learning and iterative training to greatly improve feature *** approach allows incorporating uncertainty quantification into the deep learning analysis and also enables rapid automated experimental workflows where retraining of the network to compensate for out-of-distribution drift due to subtle change in imaging conditions is substituted for human operator or programmatic selection of networks from the *** methodology can be further applied to machine learning workflows in other imaging areas including optical and chemical imaging.

关键词： learning experiment enable

Sicilian serpentinite xenoliths containing abiotic organics with nanodiamond clusters as key model for prebiotic processes

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Geoscience Frontiers 2021年第1期12卷 255-263页

作者： sergei K.Simakov Vittorio Scribano Nikolai N.Mel’Nik Germana Barone LLC“ADAMANT”Skolkovo Participant Tikhoretsky 10/1-61St.Petersburg194064Russia Department of Biological Geological and Environmental SciencesUniversity of CataniaCorso Italia 55-I-95129 CataniaItaly Lebedev Physics Institute Russian Academy of SciencesLeninsky Pr.53Moscow119991Russia

Rock fragments from the deepest parts of a buried hydrothermal system belonging to the Mesozoic Tethys Ocean entered as xenoliths in a Miocenic diatreme,hence brought to the surface,in the Hyblean Plateau(Sicily).Some xenoliths consist of strongly serpentinized ultramafic rocks bearing blebs of abiotic organic matter,where clusters of amorphous carbon nanoparticles,including nanodiamonds,are *** an occurrence conjures up established hypotheses that diamond surfaces are suitable catalytic platforms stimulating the assemblage of complex bio-organic molecules relevant to the emergence of life on *** appearance of bio-organic molecules under primitive Earth conditions is one of the major unsolved questions on the origin of *** we report new micro-Raman spectra on blebs of abiotic organic matter from a selected *** bands were related to hydrogenated nanocrystalline diamonds,with size of nearly 1-1.6 nm,formed from organics at low pressures and *** particular,diamond surfaces can give rise to crystalline interfacial water layers that may have played a fundamental role in the early biosphere evolution as a good medium for rapidly transporting positive charges in the form of hydrated ***,proton gradients in alkaline hydrothermal vents along oceanic ridges are generally viewed as key pre-biotic *** general,serpentinites span the entire geological record,including prebiotic *** hydrous ultramafic rocks often display evidence of abiotic carbon species,both organic and inorganic,including nanodiamonds,being also capable to give rise to chemiosmotic processes and proton gradients necessary to the organisms,such as the"Last Universal Common Ancestor"(LUCA),in the prebiotic Earth.

关键词： Hydrothermal systems Nanocarbons Sulfides Fr-t synthesis Abiogenesis LUCA,Sicily Micro-Raman

Cationic Polymerization of Isobutylene and C4 Mixed Feed Using Complexes of Lewis Acids with Ethers: A Comparative Study

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Chinese Journal of Polymer Science 2019年第9期37卷 891-897页

作者： Dmitriy I. Shiman Ivan A. Berezianko Irina V. Vasilenko sergei V. Kostjuk Research Institute for Physical Chemical Problems of the Belarusian State University 14 Leningrads kaya St. Minsk 220006 Belarus Department of Chemistry Belarusian State University 14 Leningradskaya st. Minsk 220006 Belarus Sechenov First Moscow State Medical University Institute for Regenerative Medicine 8-2 Trubetskaya st. Moscow 119991 Russia

The cationic polymerization of C4 mixed feed and isobutylene co-initiated by AlCl3xOiPr2,iBuAlC12xnOiPr2, and [emim]Cl- FeCl3xnOiPr2 ([emim]Cl: 1 -ethyl-3-methylimidazolium chloride) has been investigated. AlCl3xOiPr2 co-initiated cationic polymerization of C4 mixed feed proceeds at a lower rate than polymerization of isobutylene affording polymers with higher molecular weight. Complexes of iBuAlCh with di isopropyl ether of different compositions are more suitable co-initiators than AlCl3xOiPr2 for the synthesis of highly reactive polyisobutylene (HR PIB) from C4 mixed feed due to their higher activity in the polymerization as well as possibility to prepare polyisobutylenes with lower molecular weight and higher content of exo-olefin end groups. However, iBuA1C12 needs activating via addition of external water (initiator) and/or interaction with salts hydrates in order to increase the reaction rate and the saturated monomer conversion.[Emim]Cl-FeC13/iPr2O is a quite promising catalyst for the preparation of HR PIB with high exo-olefin end group content (> 80%) and relatively low polydispersity (Mw/Mn < 2.8) via cationic polymerization of C4 mixed feed. The sonication of reaction mixture in case of using [emim]Cl-FeCh allowed increasing the reaction rate and decreasing the molecular weight.

关键词： Cationic polymerization Isobutylene C4 mixed feed Highly reactive polyisobutylene

Synaptic receptors for low pH in extracellular space:metabotropic receptors are an underestimated factor in stroke

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Neural Regeneration Research 2020年第11期15卷 2033-2034页

作者： sergei V.Fedorovich Tatsiana G.Dubouskaya Tatsiana V.Waseem Institute of Biophysics and Cell Engineering MinskBelarus Department of Biochemistry Belarusian State UniversityMinskBelarus Department of Pharmacology University of OxfordOxfordUK(Waseem TV)

In the brain,extracellular pH could decrease in certain ***,however,is especially attributable for *** accumulation in the absence of anaerobic respiration is the main,but not the only,reason for lowering pH in this condition(Wemmie et al.,2013).In addition,local pH changes in the synaptic cleft may result from the release of acidic content of synaptic vesicles(Sinning and Hubner,2013).Acidification is able to damage or even kill a *** damaging effect of low pH can be mediated by a direct effect of protons on enzymes or transport *** can also,however,be mediated by specific receptors(Wemmie et al.,2013;Levin and Buck,2015).The most well studied class of pH receptors is ionotropic acid-sensing ion channels(ASIC).These are ion channels which are permeable for sodium and *** open in response to extracellular *** of these receptors could lead to neuronal death(Wemmie et al.,2013).ASIC-induced neuronal death is appeared to be involved in stroke-induced brain *** suggestion is supported by the fact that amiloride,which inhibits ASIC,has a neuroprotective effect in stroke(Xiong et al.,2004).

关键词： al. protective damage

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

Phylogenomics of Allium section Cepa(Amaryllidaceae)provides new insights on domestication of onion

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Plant Diversity 2021年第2期43卷 102-110页

作者： Ziyoviddin Yusupov Tao Deng sergei Volis Furkat Khassanov Dilmurod Makhmudjanov Komiljon Tojibaev Hang Sun CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201China International Joint Lab for Molecular Phylogeny and Biogeography Institute of BotanyAcademy Sciences of UzbekistanTashkent100125Uzbekistan University of Chinese Academy of Sciences BeijingChina

Allium ***(Amaryllidaceae)comprises economically important plants,yet resolving the phylogenetic relationships within the section has been difficult as nuclear and chloroplast-based phylogenetic trees have been *** now,phylogenetic studies of the section have been based on a few *** this study,we sequenced the complete chloroplast genome(plastomes)of four central Asian species of ***:Allium oschaninii,***,*** and *** chloroplast(cp)genomes included 114 unique genes of which 80 coded *** protein-coding genes were highly variable and therefore promising for future phylogenetic and phylogeographic *** plastome-based phylogenetic tree of Allium *** revealed two separate clades:one comprising the central Asian species ***,***,and ***,and another comprising ***,***,and two cultivated species,*** and *** findings contradict previously reported phylogenies that relied on ITS and *** explanations for this discrepancy are related to interspecific hybridization of species ancestral to *** and *** followed by chloroplast capture;however,this is impossible to prove without additional *** results suggest that the central Asian Allium species did not play a role in the domestication of the common *** the chloroplast genes,rpoC2 was identified as a gene of choice in further phylogeographical studies of the genus Allium.

关键词： Chloroplast genome SNP Phylogeny Chloroplast capture

Conservation implications of population genetic structure in a threatened orchid Cypripedium tibeticum

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Plant Diversity 2019年第1期41卷 13-18页

作者： Jian-Ling Guo Wen-Juan Cao Zhi-Min Li Yong-Hong Zhang sergei Volis Life Science Department Yunnan Normal University Kunming Institute of Botany Chinese Academy of Sciences

Cypripedium tibeticum is a threatened orchid which efficient conservation requires knowledge of its extent and structure of genetic variation. Using two chloroplast DNA fragments(rps16 and trnL-F), we analyzed 157 individuals from 9 populations representing the species range in China. Seven haplotypes were identified. C. tibeticum had high total genetic diversity(H_T=0.80) with major contribution to this diversity made by among-population component(G_ST=0.64, Ф_ST= 0.86). However, despite high population differentiation there was no clear phylogeographic structure. The populations CY and DC made the greatest contribution to the total gene diversity as well as allelic richness. The possible mechanisms and implications of these findings for conservation of the species are discussed.

关键词： Cypripedium tibeticum Orchid genetic diversity Population differentiation East Himalaya-Hengduan mountains Conservation strategy

Efficient Gene Targeting in Maize Using Inducible CRISPR-Cas9 and Marker-free Donor Template

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Molecular Plant 2020年第8期13卷 1219-1227页

作者： Pierluigi Barone Emily Wu Brian Lenderts Ajith Anand William Gordon-Kamm sergei Svitashev Sandeep Kumar Corteva AgriscienceTM JohnstonIA 50131USA

CRISPR-Cas9 is a powerful tool for generating targeted mutations and genomic ***,precise gene insertion or sequence replacement remains a major hurdle before application of CRISPR-Cas9 technology is fully realized in plant ***,we report high-frequency,selectable marker-free intra-genomic gene targeting(GT)in *** shock-inducible Cas9 was used for generating targeted double-strand breaks and simultaneous mobilization of the donor template from pre-integratad *** construct was designed such that release of the donor template and subsequent DNA repair activated expression of the selectable marker gene within the donor *** approach generated up to 4.7%targeted insertion of the donor sequence into the target locus in TO plants,with up to 86%detected donor template release and 99%mutation rate being observed at the donor loci and the genomic target site,*** previous in planta or intra-genomic homologous recombination reports in which the original chimeric GT plants required extensive progeny screening in the next generation to identify non-chimeric GT individuals,our method provides non-chimeric heritable GT in one generation.

关键词： donor template insertion

Fuzzy Aggregator Based Energy Aware RPL Routing for IoT Enabled Forest Environment

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Computers, Materials & Continua 2022年第8期72卷 4039-4055页

作者： S.Srividhya Suresh Sankaranarayanan sergei A.Kozlov Joel J.P.C.Rodrigues Department of Data Science and Business Systems School of ComputingSRM Institute of Science and TechnologyChennai603203TamilnaduIndia Department of Networking and Communications School of ComputingSRM Institute of Science and TechnologyChennai603203TamilnaduIndia ITMO University St.PetersburgRussia Senac Faculty of Ceará FortalezaCEBrazil Instituto de Telecomunicações Covilhã6201-001Portugal

Forested areas are extremely vulnerable to disasters leading to environmental *** Fire is one among them which requires immediate *** are lot of works done by authors where Wireless Sensors and IoT have been used for forest fire ***,towards monitoring the forest fire and managing the energy efficiently in IoT,Energy Efficient Routing Protocol for Low power lossy networks(E-RPL)was *** were challenges about the scalability of the network resulting in a large end-to-end delay and less packet delivery which led to the development of Aggregator-based Energy Efficient RPL with Data Compression(CAAERPL).Though CAA-ERPL proved effective in terms of reduced packet delivery,less energy consumption,and increased packet delivery ratio for varying number of nodes,there is still challenge in the selection of aggregator which is based purely on probability percentage of *** has been research work where fuzzy logic been employed for Mobile Ad-hoc Routing,RPL routing and cluster head selection in Wireless *** has been no work where fuzzy logic is employed for aggregator selection in Energy Efficient *** accordingly,we here have proposed Fuzzy Based Aggregator selection in Energy-efficient RPL for region thereby forming DODAG for communicating to Fog/*** here have developed fuzzy inference rules for selecting the aggregator based on strength which takes residual power,Node degree,and Expected Transmission Count(ETX)as input *** Fuzzy Aggregator Energy Efficient RPL(FA-ERPL)based on fuzzy inference rules were analysed against E-RPL in terms of scalability(First and Half Node die),Energy Consumption,and aggregator node energy *** the analysis,it was found that FA-ERPL performed better than *** were simulated using MATLAB and results.

关键词： Fuzzy logic aggregator IoT RPL routing wireless sensor network

Magnetic field annihilation and charged particle acceleration in ultra-relativistic laser plasmas

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High Power Laser Science and Engineering 2021年第1期9卷 8-28页

作者： Yan-Jun Gu sergei VBulanov Institute of Physics of the ASCR ELI-BeamlinesNa Slovance 218221 PragueCzech Republic Institute of Laser Engineering Osaka UniversityOsaka 565-0871Japan Kansai Photon Research Institute National Institutes for Quantum and Radiological Science and Technology8-1-7 Kizugawa-shiKyoto 619-0215Japan

Magnetic reconnection driven by laser plasma interactions attracts great interests in the recent decades. Motivated by the rapid development of the laser technology, the ultra strong magnetic field generated by the laser-plasma accelerated electrons provides unique environment to investigate the relativistic magnetic field annihilation and reconnection. It opens a new way for understanding relativistic regimes of fast magnetic field dissipation particularly in space plasmas,where the large scale magnetic field energy is converted to the energy of the nonthermal charged particles. Here we review the recent results in relativistic magnetic reconnection based on the laser and collisionless plasma *** basic mechanism and the theoretical model are discussed. Several proposed experimental setups for relativistic reconnection research are presented.

关键词： laboratory astrophysics laser plasmas interactions particle acceleration high energy density physics