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Plant-Arthropod Associations from the Lower Miocene of the Most Basin in Northern Bohemia(Czech Republic):A Preliminary Report

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Acta Geologica sinica(English Edition) 2010年第4期84卷 903-914页

作者： Jakub PROKOP Torsten WAPPLER stanislav KNOR Zlatko KVACEK Department of Zoology Charles UniversityPragueCzech Republic steinmann Institute Section PalaeontologyUniversity of BonnBonnGermany Institute of Geology and Palaeontology Charles UniversityPragueCzech Republic

Terrestrial plants and insects currently account for the majority of the Earth＇s biodiversity, and approximately haft of insect species are herbivores. Thus, insects and plants share ancient associations that date back more than 400 Myr. However, investigations of their past interactions are at the preliminary stages in Western Europe. Herein, we present the first results of our study of various feeding damage based on a dataset of nearly 3500 examined plant specimens from the Lower Miocene of the Lagerstaette Bflina Mine in the Most Basin, Czech Republic. This site provides a unique view of the Neogene freshwater ecosystems. It has long been studied by scientists working in different branches of sedimentology, paleobotany, and paleozoology. The fossils are preserved in three characteristic horizons overlaying the coal seam （Clayey superseam Horizon, Delta sandy Horizon, and Lake Clayey Horizon）, reflecting paleoenvironmental changes in a short time period of development. The trace fossils are classified as functional feeding groups or ＂guilds＂, without searching for a direct cause or a recent analog host relation. Approximately 23% of specimens of dicotyledonous plant leaves were found to be damaged and associated with some leaf ＂morphotypes＂. Deciduous plant-host taxa, and those with a chartaceous texture typical of riparian habitats, were frequently damaged, such as Populus, recorded with two species Populus zaddachii and Populus populina （57.9% and 31% herbivory levels, respectively）, followed by Acer, Alnus, and Carya, averaging almost 30% of damaged leaves/leaflets. There has been evidence of 60 damage types （DT） representing all functional feeding groups recorded at the Bflina Mine, including 12 types of leaf mines and 16 gall- type DT. In total, Lower Miocene of the Lagerstaette Bilina Mine exhibits a high level of external foliage feeding types （23.7%）, and a low level of more specialized DT, such as galls （4.3%） and leaf mines （〈1%）. A broader comparison b

关键词： plant-insect interaction paleoecology climate change Neogene Early Miocene Most Basin BflinaMine Czech Republic

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skyline-Based Registration of 3D Laser scans

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Geo-spatial Information science 2011年第2期14卷 85-90页

作者： Andreas Nüchter stanislav Gutev Dorit Borrmann Jan Elseberg Automation Group School of Engineering and Science Jacobs University Bremen gGmbH

Acquisition and registration of terrestrial 3D laser scans is a fundamental task in mapping and modeling of cities in three dimensions. To automate this task marker-flee registration methods are required. Based on the existence of skyline features, this paper proposes a novel method. The skyline features are extracted from panoramic 3D scans and encoded as strings enabling the use of string matching for merging the scans. Initial results of the proposed method in the old city center of Bremen are presented.

关键词： LIDAR point cloud processing 3D city modeling marker-free registration place recognition

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Effects of Morphological Integrity of secondary Feather on Their Drag Reduction in Pigeons

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Journal of Bionic Engineering 2022年第5期19卷 1422-1438页

作者： Qian Li Huan shen Qingfei Han Aihong Ji Zhendong Dai stanislav N.Gorb Institute of Bio-Inspired structure and surface Engineering College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016China Department of Functional Morphology and Biomechanics Kiel UniversityAm Botanischen Garten 924118 KielGermany

Flight feathers of birds interact with the air flow during *** the observed low drag and high lift values at wind speeds from 9.0 to 19.8 m/s can be achieved due to the feather aerodynamics remains *** the present paper,we tested and compared morphological changes,drag reduction and flow visualization results of intact,damaged,and artificial feathers at different wind speeds in a wind *** the analysis of the drag force and resultant force angle,we proved that the integrity of feathers,whose barbs are usually closely interconnected,played an important role in the drag,which potentially triggers excellent drag reduction *** wind tunnel tests indicated that intact secondary feathers had a surprisingly high maximum drag reduction property at v?=?9 m/s compared with the feathers,where the integrity of barbs was *** hook cascades facilitated elasticity under pressure and suitable permeability in an intact feather,when the hooks were *** was indicated that the suitable permeability of intact feathers would prevent flow separation and reduce drag force at low wind speed;at high wind speed,elasticity under pressure and suitable permeability in an intact feather would facilitate strong squeezing effect,helping feathers withstand larger aerodynamic forces to which they might be subjected during *** was revealed that the intact secondary feather is a compromise between strong lift generation and drag reduction,which has a great significance for the bird’s flight.

关键词： Morphological integrity secondary feather Drag reduction Wind tunnel smoke visualization Bioinspiration

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蝗虫脚掌微结构及其接触的有限元分析

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上海交通大学学报 2003年第1期37卷 66-69页

作者：戴振东 stanislav Gorb 南京航空航天大学机电学院设计工程系南京210016 BiologicalMicrotribologyGroup Max-Planck-InstituteforDevelopmentalBiology

用电子显微镜研究了蝗虫足掌的微结构 ,用非线性有限元方法分析足掌接触过程的变形规律、接触刚度及接触面积、气囊的作用和足掌的应力应变规律 .结果表明 ,蝗虫足掌以软性外表皮包含血浆 (液体 )的结构形式 ,有利于降低接触刚度、增加... 详细信息

用电子显微镜研究了蝗虫足掌的微结构 ,用非线性有限元方法分析足掌接触过程的变形规律、接触刚度及接触面积、气囊的作用和足掌的应力应变规律 .结果表明 ,蝗虫足掌以软性外表皮包含血浆 (液体 )的结构形式 ,有利于降低接触刚度、增加接触面积 ,并使爪垫在接触过程便产生有利于稳定附着的摩擦力 .软性外表皮内的树丛状杆组织结构会提高足掌在各种表面上的适应性。

关键词：蝗虫脚掌微结构接触过程接触面积接触刚度变形规律非线性有限元分析

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Boron isotopic variations in tourmaline from metacarbonates and associated calc-silicate rocks from the Bohemian Massif: Constraints on boron recycling in the Variscan orogen

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Geoscience Frontiers 2021年第1期12卷 219-230页

作者： Lukas Krmcek Milan Novak Robert B.Trumbull Jan Cempirek stanislav Houzar Department of Geological sciences Faculty of ScienceMasaryk UniversityKotlarska 2CZ-61137BrnoCzech Republic Institute of Geology of the Czech Academy of sciences Rozvojova 269CZ-16502Prague 6Czech Republic Brno University of Technology Faculty of Civil EngineeringAdMaS CentreVeve■rí95CZ-60200BrnoCzech Republic GFZ German Research Centre for Geosciences TelegrafenbergD-14473PotsdamGermany Department of Mineralogy and Petrography Moravian MuseumZelnyTrh 6CZ-67401BrnoCzech Republic

Various metacarbonate and associated calc-silicate rocks form minor but genetically significant components of the lithological units in the Bohemian Massif of the Variscan orogen in Central *** rocks vary in terms of their lithostratigraphy,chemical composition and mineral assemblage(dolomite/calcite ratio,silicate abundance).Tourmaline is present in five paragenetic settings within the metacarbonate and calc-silicate ***Ⅰcomprises individual,euhedral,prismatic grains and grain aggregates in a carbonate-dominant(calcite±dolomite)matrix poor in ***Ⅱis characterized by euhedral to subhedral grains and coarse-to fine-grained aggregates in silicate-rich layers/nests within metacarbonate bodies whereas typeⅢoccurs as prismatic grains and aggregates at the contact zones between carbonate and associated silicate host ***Ⅳis in veins crosscutting metacarbonate bodies,and typeⅣtourmaline occurs at the exocontacts of elbaite-subtype granitic *** from the different settings shows distinctive compositional *** for typeⅠare Mg-rich compositions,with fluor-uvite>dravite>>*** from typeⅡsilicate-rich layers/nests are highly variable,corresponding to oxy-schorl,magnesio-foitite,Al-rich dravite and *** for typeⅢtourmalines are Ca,Ti-bearing oxy-dravite *** typeⅣveins feature dravite and fluor-uvite tourmaline compositions whereas typeⅤtourmaline is Li,F-rich *** is the only Bbearing phase in paragenetic typesⅠ-Ⅳ,where it is characterised by two principal ranges of B-isotope composition(δ^11B=-13‰to-9‰and-18‰to-14‰).These ranges correspond to regionally different units of the Moldanubian ***,the svratka Unit(Moldanubian Zone s.l.)contains only isotopically lighter tourmaline(δ^11B=-18‰to-14‰),whereas metacarbonates in the Poli?ka unit(Teplá-Barrandian Zone)and Olesnice unit(Moravicum of the Moravo-silesian Zone)has exclusively isotopically heav

关键词： Boron isotopes Tourmaline Metacarbonates Moldanubicum Variscan orogeny

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Color-coded perfluorocarbon nanodroplets for multiplexed ultrasound and photoacoustic imaging

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Nano Research 2019年第4期12卷 741-747页

作者： Daniela Y. santiesteban Kristina A. Hallam steven K. Yarmoska stanislav Y. Emelianov Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA school of Electrical & Computer Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Laser-activated perfluorocarb on n anodroplets are an emerging class of phase-cha nge, dual-c ontrast age nts that can be utilized in ultraso und and photoacoustic imaging. Through the ability to differe ntiate subpopulations of nano droplets via laser activatio n at differe nt wavelengths of n ear-infrared light, optically-triggered color-coded perfluorocarb on nano droplets prese nt themselves as an attractive tool for multiplexed ultrasound and photoacoustic imaging. In particular, laser-activated droplets can be used to provide quantitative spatiotemporal information regarding distinct biological targets, allowing for their potential use in a wide range of diagnostic and therapeutic applications. In the work prese nted, laser-activated color-coded perfluorocarb on nan odroplets are syn thesized to selectively resp ond to laser irradiati on at corresp on ding wavele ngths. The dyn amic ultraso und and photoacoustic signals produced by laser-activated perfluorocarbon nano droplets are evaluated in situ prior to implementation in a murine model. In vivo, these particles are used to distinguish unique particle trafficking mechanisms and are show n to provide ultraso und and photoacoustic contrast for up to 72 hours within lymphatics. Overall, the con ducted studies show that laser-activated color-coded perfluorocarbo n nano droplets are a promising agent for multiplexed ultraso und and photoacoustic imaging.

关键词： multiplexed imaging perfluorocarbon nanodroplets photoacoustic imaging ultrasound imaging molecular targets

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The Role of Vanes in the Damping of Bird Feathers

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Journal of Bionic Engineering 2023年第4期20卷 1646-1655页

作者： Kai Deng Hamed Rajabi Alexander Kovalev Clemens F.schaber Zhendong Dai stanislav N.Gorb Functional Morphology and Biomechanics Institute of ZoologyKiel University24098KielGermany school of Engineering London South Bank UniversityLondonSE10AAUK Institute of Bioinspired structure and surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing210026People’s Republic of China

Bird feathers sustain bending and vibrations during *** unwanted vibrations could potentially cause noise and flight *** could alter the system response,resulting in improving quiet flight,stability,and *** of feathers are known to be indispensable for supporting the aerodynamic function of the *** relationship between the hierarchical structures of vanes and the mechanical properties of the feather has been previously ***,still little is known about their relationship with feathers’damping ***,the role of vanes in feathers’damping properties was *** vibrations of the feathers with vanes and the bare shaft without vanes after step deflections in the plane of the vanes and perpendicular to it were measured using high-speed video *** presence of several main natural vibration modes was observed in the feathers with *** trimming vanes,more vibration modes were observed,the fundamental frequencies increased by 51-70%,and the damping ratio decreased by 38-60%.Therefore,we suggest that vanes largely increase feather damping *** mechanisms based on the morphology of feather vanes are *** aerodynamic damping is connected with the planar vane surface,the structural damping is related to the interlocking between barbules and barbs,and the material damping is caused by the foamy medulla inside barbs.

关键词： Bird Feather Vibrations Damping Bionic

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Environmental Changes and Human Impacts on Landscapes near Medieval steklyanukha-2 Fortress in Russia from Early Iron Age to Modern Times

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Chinese Geographical science 2023年第1期33卷 69-84页

作者： RAZJIGAEVA Nadezhda GANZEY Larisa KORNYUsHENKO Tatiana GREBENNIKOVA Tatiana KUDRYAVTsEVA Ekaterina PIsKAREVA Yana PROKOPETs stanislav Pacific Geographical Institute Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia Institute of History Archaeologyand Ethnography of the Peoples of the Far EastFar Eastern Branch of the Russian Academy of SciencesVladivostok 690091Russia

The development of landscapes in one of the most populated river basins of the southern Russian Far East was studied using pollen and diatom data. The study sites were a multi-layered mountain fortress, steklyanukha-2, and an Upper Holocene high floodplain sequence of the steklyanukha River. Buried soil from the fluvial section acts as an environmental archive of the time in which people from the Yankovskaya archeological cultures settled in the river basin. The soil was formed under conditions of decreasing water supply in the valley and prolonged droughts. Findings of pollen Fagopyrum and Urtica signal economic activity in the Early Iron *** lake sediments accumulated from 1.6 to 0.5 kyr, when the valley was actively developed during the Middle Ages. There are signals of the development of secondary birch and oak forests. In the cultural layer of the fortress and lake sediments formed in the Middle Ages, Ambrosia and Xanthium pollens were found and are reliable evidence of agricultural activity in the valley. The pollens of plants typically seen in human-disturbed areas were also found. Indirect evidence of human activity includes non-pollen *** study of diatoms in a depression near a rampart confirmed the archaeologists' assumption that it was used as a water reserve. Pollen spectra from surface soils reflect agricultural activity in the river basin since the second half of the 19th century. The largest amount of pollen of alien and synanthropic plants and weeds, as well as spores of pathogenic fungi and fire indicators, were found here.

关键词： ancient agriculture mountain fortress humidity changes pollen diatoms

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A Method Based on Thermo-Vibrational Effects for Hydrogen Transportation and storage

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Fluid Dynamics & Materials Processing 2024年第12期20卷 2775-2788页

作者： Tatyana P.Lyubimova sergey A.Plotnikov Albert N.sharifulin Vladimir Ya.Modorskii s.Neshev stanislav L.Kalyulin Institute of Continuous Media Mechanics Ural Branch of Russian Academy of SciencesPerm614013Russia Aerospace Faculty Perm National Research Polytechnic UniversityPerm614990Russia

Transporting and storing hydrogen is a complex technological task.A typical problem relates to the need to minimize the strength of fluid motion and heat transfer near the walls of the *** this work this problem is tackled numerically assuming an infinite cavity of pipe square cross-section,located in a constant external temperature *** particular,a method based on the application of vibrations to suppress the gravitational convection mechanism is explored.A parametric investigation is conducted and the limits of applicability of the method for small Grashof numbers(10e4)are *** is shown that it is possible to minimize the intensity of the vibrogravitational flow for any values of the problem parameters if correction factors are *** results obtained can be applied in technological processes associated with the transportation,storage and use of hydrogen:pumping the working fluid through pipes,storage in tanks,as well as flow processes in the combustion chambers of power plants.

关键词： Thermal vibration convection vibrations vortex structures square pipe cavity hydrogen transportation and storage

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Textural changes in metallurgical coke prepared with polyethylene

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 969-973页

作者： stanislav s.Gornostayev Jyrki J.Heino Tommi M.T.Kokkonen Hannu T.Makkonen satu M.M.Huttunen Timo M.J.Fabritius Laboratory of Process Metallurgy University of Oulu

The effect of high-density polyethylene （HDPE） on the textural features of experimental coke was investigated using polar- ized-light optical microscopy and wavelet-based image analysis. Metallurgical coke samples were prepared in a laboratory-scale furnace with 2.5%, 5.0%, 7.5%, 10.0%, and 12.5% HDPE by mass, and one sample was prepared by 100% coal. The amounts and distribution of textures （isotropic, mosaic and banded） and por^s were obtained. The calculations reveal that the addition of HDPE results in a decrease of mosaic texture and an increase of isotropic texture. Ethylene formed from the decomposition of HDPE is considered as a probable reason for the texture modifications. The approach used in this study can be applied to indirect evaluation for the reactivity and strength of coke.

关键词： metallurgical coke texture image analysis polyethylene

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