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Giga- and terahertz-range nanoemitter based on peapod structure

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Nano Research 2015年第8期8卷 2595-2602页

作者： Michail M. Slepchenkov Anna S. Kolesnikova George V. Savostyanov1 Igor S. Nefedov Ilya V. Anoshkin Albert G. Nasibulin olga e. Glukhova Department of Physics Saratov State University Saratov 410012 Russia Department of Radio Science and engineering Aalto University Aalto P.O. Box 13000 Finland kolkovo Institute of Science and Technology Skolkovo 143025 Russia

We propose a theoretical model of a nanoemitter for giga- and terahertz-range waves. The model is based on a peapod structure comprising a carbon nanotube with chiral indices （10, 10）. Three encapsulated and partially polymerized fuUerene C60 molecules and a positively charged C60 fullerene are trapped inside the nanotube. The motion of the charged fullerene and the radiation frequency were controlled using an external electric field. Stable terahertz radiation at a frequency of 0.36 THz was produced at 300 K with an external electrical field of 10 V/μm. Stable radiation in the gigahertz range was observed at 50 K with an electric field below 10 V/m. A theoretical simulation was performed using the tight-binding molecular dynamics method with a description of the van der Waals interaction by the Morse potential. The system described by the theoretical model was experimentally observed.

关键词： fullerenes nanotubes electronics simulations molecular modeling

New Findings of Latest early Olenekian(early Triassic)Fossils in South Primorye,Russian Far east,and Their Stratigraphical Significance

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Journal of earth Science 2021年第3期32卷 554-572页

作者： Yuri D.Zakharov Liana G.Bondarenko Alexander M.Popov olga P.Smyshlyaeva Far eastern Geological Institute Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

Information on latest early Olenekian(latest Smithian)ammonoids is available apparently from only seven regions of the world,including South *** Smithian evidences on this topic are recorded from the West SMID(abbreviation from the Russian name of the quarry:"Building Materials and Details"),east SMID and Golyj Cape areas in South *** provides additional information on systematic composition of latest Smithian ammonoid,as well as conodont and brachiopod assemblages from the recently identified Shimanskyites shimanskyi Zone,located between lower Olenekian Anasibirites nevolini Zone and upper Olenekian Tirolites subcassianus *** are many common ammonoid species in the Shimanskyites shimanskyi Zone and the underlying Anasibirites nevolini Zone,e.g.,Prosphingitoides sp.,Arctoceras septentrionale(Diener),Churkites syskoi Zakharov et Shigeta,Submeekoceras?subhhydaspis(Kiparisova),Prionites markevichi Zakharov et Smyshlyaeva,?Anasibirites?simanenkoi Zakharov et Smyshlyaeva,Xenoceltites?subvariocostatus Zakharov et Smyshlyaeva,and Mianwaliites zimini Zakharov et *** base of the Shimanskyites shimanskyi Zone,marked by a negativeδ13Corg excursion in the Kamenushka-2 Section by our previous study,coincides with the FO(first occurrence)of ammonoids Shimanskyites shimanskyi Zakharov et Smyshlyaeva and Glyptophiceras ***(Waagen)and conodont Hindeodella budurovi *** zone is characterized additionally by some fossils common for the overlying upper Olenekian Tirolites subcassianus Zone:ammonoids of the genus Kamenushkaites,brachiopods Bittnerihyris margaritovi(Bittner)and Lepismatina *** conodont?Neogondolella?(=?Borinella)jubata *** latest Smithian ammonoids recorded from the Shimanskyites shimanskyi Zone totally consist of 30 taxa belonging to 11 families(Sageceratidae,Ussuiriidae,Aspenitidae,Paranannitidae,Arctoceratidae,Proptychitidae,?Galfetitidae,Prionitidae,?Kashmiritidae,Xenoceltitidae and Palaeophyllitidae).Th

关键词： ammonoids conodonts brachiopods biostratigraphy Smithian Russia

Rainfall Forecasting Using Machine Learning Algorithms for Localized events

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Computers, Materials & Continua 2022年第6期71卷 6333-6350页

作者： Ganapathy Pattukandan Ganapathy Kathiravan Srinivasan Debajit Datta Chuan-Yu Chang Om Purohit Vladislav Zaalishvili olga Burdzieva Centre for Disaster Mitigation and Management Vellore Institute of TechnologyVellore632014India School of Computer Science and engineering Vellore Institute of TechnologyVellore632014India Department of Computer Science and Information engineering National Yunlin University of Science and TechnologyYunlin64002Taiwan Service Systems Technology Center Industrial Technology Research InstituteHsinchuTaiwan School of Information Technology and engineering Vellore Institute of TechnologyVellore632014India Geophysical Institute of Vladikavkaz Scientific Centre Russian Academy of Sciences(RAS)VladikavkazRussian Federation

A substantial amount of the Indian economy depends solely on ***,on the other hand,plays a significant role in agriculture–while an adequate amount of rainfall can be considered as a blessing,if the amount is inordinate or scant,it can ruin the entire hard work of the *** this work,the rainfall dataset of the Vellore region,of Tamil Nadu,India,in the years 2021 and 2022 is forecasted using several machine learning *** engineering has been performed in this work in order to generate new features that remove all sorts of autocorrelation present in the *** removal of autocorrelation,the data could be used for performing operations on the time-series data,which otherwise could only be performed on any other regular regression *** work uses forecasting techniques like the AutoRegessive Integrated Moving Average(ARIMA)and exponential smoothening,and then the time-series data is further worked on using Long Short Term Memory(LSTM).Later,regression techniques are used by manipulating the *** work is benchmarked with several evaluation metrics on a test dataset,where XGBoost Regression technique outperformed the *** uniqueness of this work is that it forecasts the daily rainfall for the year 2021 and 2022 in Vellore *** work can be extended in the future to predict rainfall over a bigger region based on previously recorded time-series data,which can help the farmers and common people to plan accordingly and take precautionary measures.

关键词： Time-series ARIMA LSTM regression rainfall

Landscape and scale-dependent spatial niches of bats foraging above intensively used arable fields

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ecological Processes 2017年第1期6卷 249-263页

作者： olga Heim Lukas Lorenz Stephanie Kramer-Schadt Kirsten Jung Christian C.Voigt Jana A.eccard Leibniz Institute for Zoo and Wildlife Research Alfred-Kowalke-Str.1710315 BerlinGermany Animal ecology Institute of Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany Institute of evolutionary ecology and Conservation Genomics University of UlmAlbert-Einstein-Allee 1189069 UlmGermany Department of Animal Behaviour Freie Universität BerlinTakustr.314195 BerlinGermany

Introduction:Bats are threatened by agricultural intensification,and although bat ecology in agricultural landscapes is in the focus of current research,the effects of interacting spatiotemporal factors on species-specific bat activity above farmland remain *** aim was to identify spatiotemporal factors and their interactions relevant for the activity of bat species above conventionally managed arable ***:We repeatedly monitored relative bat activity above open arable fields in Germany using acoustic *** used site-related biotic and abiotic factors and landscape characteristics across five spatial scales,their combinations,and interactions to identify those factors which best explain variation in bat ***:Numerous interactions between landscape characteristics and the insect abundance affected bat activity above *** instance,Pipistrellus pipistrellus became more active with increasing insect abundance,but only above fields with a low proportion of woody vegetation cover in the ***,the level of bat activity in summer depended on landscape *** example,the activity of Pipistrellus nathusii was relatively low in summer above fields that were surrounded by vegetation patches with a high degree of edge complexity(e.g.,hedgerow).However,the activity remained at a relatively high level and did not differ between seasons above fields that were surrounded by vegetation patches with a low degree of edge complexity(e.g.,roundly shaped forest patch).Conclusions:Our results revealed that landscape characteristics and their interactions with insect abundance affected bat activity above conventionally managed fields and highlighted the opportunistic foraging behavior of *** improve the conditions for bats in agricultural landscapes,we recommend re-establishing landscape heterogeneity to protect aquatic habitats and to increase arthropod availability.

关键词： AgroScapeLabs european bat species Agriculture Landscape Multi-scale habitat modeling ecosystem service ConservationAgroScapeLabs european bat species Agriculture Landscape Multi-scale habitat modeling ecosystem service Conservation

Morphological and ecological divergence in two populations of european glass lizard,Pseudopus apodus(Squamata:Anguidae)

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Zoological Research 2020年第2期41卷 172-181页

作者： olga Jovanovic Glavas Paula Pocanic Vanja Lovric Lorena Derezanin Zoran Tadic Duje Lisicic Department of Biology University of OsijekOsijek 31000Croatia Department of Animal Physiology Faculty of ScienceUniversity of ZagrebZagreb 10000Croatia

The european glass lizard,Pseudopus apodus(Pallas,1775),is a large,legless lizard with wide distribution across south-eastern europe and eastern and central *** date,morphological diversification among populations on a geographically small scale has not yet been reported in this ***,we investigated the morphological variations and corresponding differences in habitat utilization between two populations of *** inhabiting the same biogeographical zone within a relatively close geographic *** hypothesized that minor differences in habitat could induce a significant level of morphological differentiation,thus indicating morphological plasticity in this species on a small geographical *** sampled 164 individuals(92 from the Croatian mainland and 72 from the island of Cres).Results showed that *** indeed exhibited morphological differences between populations in the same biogeographical zone within a relatively close geographic area,with the Cres Island individuals being generally larger than the individuals from the *** ecological characteristics were similar in both populations(e.g.,soil temperature,distance to hiding place),whereas others were distinct(e.g.,air temperature and humidity).In addition,vegetation cover differed between the two sites,with more vegetation present on the mainland than on the ***,the Cres Island population showed clear sexual dimorphism,which was absent in the mainland population.

关键词： Mediterranean Morphology Sauria Sexual dimorphism

effect of functional groups on the crystallization of ferric oxides/oxyhydroxides in suspension environment

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Frontiers of Materials Science 2012年第4期6卷 297-303页

作者： Qiong ZHOU olga ALBeRT Hua DeNG Xiao-Long YU Yang CAO Jian-Bao LI Xin HUANG State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China College of Materials and Chemical engineering Hainan UniversityHaikou 570228China eRC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry University Medical Center of the Johannes Gutenberg University MainzD-55128 MainzGermany Department of Oral and Maxillofacial Surgery Beiji-ng Stomatological HospitalCapital Medical LJniversityBeijing 100050China

This paper investigated the effects of five kinds of Au surfaces terminated with and without functional groups on the crystallization of ferric oxides/oxyhydroxides in the suspension condition. Self-assembled monolayers （SAMs） were used to create hydroxyl （-OH）, carboxyl （-COOH）, amine （-NH2） and methyl （-CH3） functionalized surfaces, which proved to be of the same surface density. The immersion time of substrates in the Fe（OH）3 suspension was divided into two time portions. During the first period of 2 h, few ferric oxide/oxyhydroxide was deposited except that e-Fe203 was detected on -NH2 surface. Crystallization for 10h evidenced more kinds of iron compounds on the functional surfaces. Goethite and maghemite were noticed on four functional surfaces, and maghemite also grew on Au surface. Deposition of ^-Fe203 was found on -OH surface, while the growth of orthorhombic and hexagon FeOOH were indicated on -NH2 surface. Considering the wide existence of iron compounds in nature, our investigation is a precedent work to the study of iron biomineralization in the suspension area.

关键词： biocrystallization suspension ferric oxide/oxyhydroxide functional group

empty nose syndrome pathogenesis and cell-based biotechnology products as a new option for treatment

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World Journal of Stem Cells 2021年第9期13卷 1293-1306页

作者： Inna M Gordiienko olga S Gubar Roman Sulik Taras Kunakh Igor Zlatskiy Alona Zlatska Biotechnology Laboratory Medical Company“Good Cells”Kyiv 03115Ukraine R.e.Kavetsky Institute of experimental Pathology Oncology and Radiobiology NAS of UkraineKyiv 03022Ukraine Institute of Molecular Biology and Genetics NAS of Ukraine Kyiv 03143Ukraine State Institute of Genetic and Regenerative Medicine National Academy of Medical Sciences of UkraineKyiv 04114Ukraine

empty nose syndrome (eNS) is a rare complication that develops after partial orcomplete turbinectomy. The main feature of eNS is paradoxical nasal obstructionfeeling despite objectively wide nasal airway. eNS pathogenesis is multifactorialand includes changes in laminar physiological airflow, disruption of mucosafunctions and deficient neural sensation. This leads to the development of eNSsymptomatology such as dyspnea, nasal dryness, nasal burning, nasalobstruction, feeling of suffocation and even comorbid psychiatric disorders thatsignificantly impairs life quality. Specific effective treatment of eNS does not existup to date. In this review we outline existing biomaterial for surgical reconstitutionof nasal anatomy and discuss the perspective of stem cell-based technologiesin eNS management. The main focus is directed to justification ofrationality application of adult mesenchymal stem cells (MSCs) from differenttissues origin and neural crest-derived stem cells (NCSCs) based on their intrinsicbiological properties. MSCs transplantation may stimulate mucosa tissueregeneration via trophic factors secretion, direct transdifferentiation into epithelialcells and pronounced immunosuppressive effect. From the other hand, NCSCsbased on their high neuroprotective properties may reconstitute nerve structureand functioning leading to normal sensation in eNS patients. We postulate thatapplication of cell-based and tissue-engineered products can help to significantlyimprove eNS symptomatology only as complex approach aimed at reconstitutionof nasal anatomy, recovery the nasal mucosa functionality and neural tissuesensation.

关键词： empty nose syndrome Stem-cell-based technologies Implants biomaterials Grafts Hydrogels Mesenchymal stem cells

望天鹅火山喷发时限的激光 ^(40)Ar/ ^(39)Ar年代学

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岩石学报 2021年第8期37卷 2521-2530,I0001-I0004页

作者：周鑫周晶 ANDReeVA olga A ANDReeVA Irina A 季建清北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室北京100871 俄罗斯科学院矿床岩石矿物与地球化学研究所莫斯科119017

在中国东北地区,望天鹅火山的覆盖范围仅次于长白山,前人测得的K-Ar年龄主要集中在2~3Ma,但其精确的喷发年代一直没有很好的限定。这是因为第四纪以来的火山岩40 Ar/39 Ar定年与较老的地质样品有显著的不同,测试过程中极其微小的偏差会... 详细信息

在中国东北地区,望天鹅火山的覆盖范围仅次于长白山,前人测得的K-Ar年龄主要集中在2~3Ma,但其精确的喷发年代一直没有很好的限定。这是因为第四纪以来的火山岩40 Ar/39 Ar定年与较老的地质样品有显著的不同,测试过程中极其微小的偏差会呈指数方式放大,带来测年结果的极大误差,难以严格限定火山喷发的年代。本文选用的激光40 Ar/39 Ar年代学方法具有样品用量小、精度高、自动化测试稳定等优点。通过增加测试次数,在数据处理中引入高斯混合模型进行统计分析,可以更准确地判别火山喷发期次。在此基础上,提出符合等时线计算要求的同位素体系“同源、同时、封闭”的数学表达是表观年龄的正态分布,对构成同一正态分布的数据计算等时线年龄,能够实现对望天鹅火山喷发时代的精细限定。结果显示,在测试精度尺度内,望天鹅火山可以看作是一期喷发的结果,喷发时限为2.73±0.18Ma。这一时限可以帮助解释北太平洋深海钻探中同一时期火山凝灰质沉积层的出现,并由此可以把2.73Ma前后的北半球大冰期事件与望天鹅火山喷发联系起来,为研究火山喷发与气候变冷效应提供一个新的实证案例。

关键词： 40 Ar/39 Ar定年等时线年龄高斯混合模型望天鹅火山

Agent-based modeling of COVID-19 outbreaks for New York state and UK:Parameter identification algorithm

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Infectious Disease Modelling 2022年第1期7卷 30-44页

作者： olga Krivorotko Mariia Sosnovskaia Ivan Vashchenko Cliff Kerr Daniel Lesnic Institute of Computational Mathematics and Mathematical Geophysics Siberian Branch of the Russian Academy of Sciences 6 Prospect Akademika Lavrentieva StreetNovosibirsk630090Russia Novosibirsk State University 2 Pirogova StreetNovosibirsk630090Russia Institute for Disease Modeling Bill&Melinda Gates FoundationSeattleUSA University of Leeds LS29JTUK

This paper uses Covasim,an agent-based model(ABM)of COVID-19,to evaluate and scenarios of epidemic spread in New York State(USA)and the *** parameters such as contagiousness(virus transmission rate),initial number of infected people,and probability of being tested depend on the region's demographic and geographical features,the containment measures introduced;they are calibrated to data about COVID-19 spread in the region of *** the first stage of our study,epidemiological data(numbers of people tested,diagnoses,critical cases,hospitalizations,and deaths)for each of the mentioned regions were *** data were characterized in terms of seasonality,stationarity,and dependency spaces,and were extrapolated using machine learning techniques to specify unknown epidemiological parameters of the *** the second stage,the Optuna optimizer based on the tree Parzen estimation method for objective function minimization was applied to determine the model's unknown *** model was validated with the historical data of *** modeled results of COVID-19 spread in New York State and the UK have demonstrated that if the level of testing and containment measures is preserved,the number of positive cases in New York State remain the same during March of 2021,while in the UK it will reduce.

关键词： epidemiology Agent-based modeling COVID-19 Interventions analysis Coronavirus data analysis Forecasting scenarios Reproduction number Optimization Parameter identification