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Robustness and efficiency of voting consensus protocols within byzantine infrastructures

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Blockchain(Research and Applications) 2021年第1期2卷 1-14页

作者： Angelo Capossele Sebastian müller Andreas Penzkofer IOTA Foundation 10405BerlinGermany Aix-marseille Universitae CNRSCentrale MarseilleI2MUMR 737313453MarseilleFrance

This paper investigates several voting consensus protocols with low computational complexity in noisy Byzantine *** computer simulations,we show that explicit randomization of the consensus protocol can significantly increase the robustness towards faulty and malicious *** identify the optimal amount of randomness for various Byzantine attack strategies on different kinds of network topologies.

关键词： Distributed systems Consensus protocols Byzantine infrastructures Simulation studies

A model for strong attenuation and dispersion of seismic P-waves in a partially saturated fractured reservoir

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Science China(Physics,mechanics & Astronomy) 2010年第8期53卷 1383-1387页

作者： BRAJANOVSKI miroslav müller Tobias m PARRA Jorge O Department of Exploration Geophysics Curtin University of Technology Geophysical Institute University of Karlsruhe Southwest Research Institute

In this work we interpret the data showing unusually strong velocity dispersion of P-waves (up to 30%) and attenuation in a relatively narrow frequency range. The cross-hole and VSP data were measured in a reservoir, which is in the porous zone of the Silurian Kankakee Limestone Formation formed by vertical fractures within a porous matrix saturated by oil, and gas patches. Such a medium exhibits significant attenuation due to wave-induced fluid flow across the interfaces between different types of inclusions (fractures, fluid patches) and background. Other models of intrinsic attenuation (in particular squirt flow models) cannot explain the amount of observed dispersion when using realistic rock properties. In order to interpret data in a satisfactory way we develop a superposition model for fractured porous rocks accounting also for the patchy saturation effect.

关键词： attenuation dispersion Biot’s slow wave poroelasticity fractures patchy-saturation

Snake-like calls in breeding tits

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Current Zoology 2021年第5期67卷 473-479页

作者： Anders Pape møller Diego GIL Wei LIANG Ecologie Systematique Evolution Universite Paris-SudCNRSAgroParisTechUniversite Paris-SaclayOrsay CedexF-91405France ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China Departamento de Ecologia Evolutiva Museo Nacional de Ciencias Naturales(CSIC)MadridE-28006Spain and ministry of Education Key Laboratory for Ecology of Tropical Islands College of Life SciencesHainan Normal UniversityHaikou571158China

Hole-nesting tits belonging to the family Paridae produce a hissing display that resembles the exhalatory hiss of a *** a predatory animal enters the nest hole of a tit,tits often hiss vigorously,while lunging their head forward and shaking their wings and tail,until the intruder *** assessed the acoustic similarity between such hiss calls from 6 species of tits,snake hisses,and tit syllables used in alarm vocalizations,as well as white noise as a *** hiss calls showed a high degree of similarity with snake hisses from 3 different snake *** hisses had lower similarity to syllable alarm calls,suggesting convergence of tit hisses in their spectral *** calls would only be effective in protecting nest boxes if nest predators responded to these *** order to test this hypothesis,we trained individual Swinhoe’s striped squirrels,Tamiops swinhoei hainanus,a common predator of egg and nestling tits,to feed at feeders in proximity to nest *** compared the aversive response of squirrels to tit’s hiss calls and white noise,presented in random *** showed a higher degree of avoidance of feeders when hiss calls were played back than when white noise was *** conclusion,our study suggests that hole-nesting birds have evolved convergent snake-like hiss calls,and that predators avoid to prey on the contents of nest boxes from which snake-like hisses emerge.

关键词： frequency-dependent selection hiss call mimicry squirrels tits

Synthesis and electronic properties of expanded 5-(hetero)arylthien-2-yl substituted 3-ethynyl quinoxalines with AIE characteristics

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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.merkt Thomas J.J.müller Institute of Organic Chemistry and macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PmmA films, along with their relationships, are comparatively investigated. moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词： absorption aggregation induced emission cross-coupling fluorescence heterocycles palladium

Light matters:Nest illumination alters egg rejection behavior in a cavity-nesting bird

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Avian Research 2022年第1期13卷 64-67页

作者： Canchao Yang Anders Pape møller Wei Liang ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China Ecologie Systématique Evolution UniversitéParis-SudCNRSAgroParisTechUniversitéParis-SaclayF-91405Orsay CedexFrance

Egg discrimination by cavity-nesting birds that build nests under dim light conditions was presumed to depend on nest luminance,although this hypothesis has rarely been *** of egg discrimination ability by cavity-nesting tits under dim light conditions may reveal the selection pressure from brood parasitism that they encounter under natural *** manipulated the intensity of luminance of nests of the Green-backed Tit(Parus monticolus),a potential cuckoo host that possesses a strong discrimination ability of non-mimetic foreign *** performed experiments to test their egg discrimination ability under different light *** results showed that Green-backed Tits discriminate against non-mimetic foreign eggs under normal light conditions in nest boxes,and this ability persisted at nest luminance as low as 4.78±1.31 lux that is several times lower than normal luminance(38.11±24.02 lux).However,egg discrimination by Green-backed Tits disappeared when nest luminance was reduced to a minimum of 0.35±0.15 *** latter value represents total darkness for *** present study shows that nest luminance plays a key role in egg discrimination by Green-backed Tits that build nests under dim light *** study provides strong experimental evidence for nest illumination altering egg rejection behavior in cavity-nesting birds.

关键词： Brood parasitism Cryptic egg Egg rejection Luminance manipulation Nest light condition

Nanoscale image of the drug/metal mono-layer interaction:Tapping A Fm-IR investigations

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Nano Research 2020年第4期13卷 1020-1028页

作者： Natalia Piergies Alexandre Dazzi ariane Deniset-Besseau Jeremie mathurin magdalena Ocwieja Czeslawa Paluszkiewicz Wojciech m.Kwiatek Institute of Nuclear Physics Polish Academy of SciencesPL-31342 KrakowPoland Laboratoire de Chimie Physique(LCP) CNRS UMR 8000Univ.of Paris-SudUniversite Paris-Saclay91405 OrsayFrance Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Sciences Niezapominajek 8PL-30239 KrakowPoland

The application of metal nanoparticles as an efficient drug delivery system is one of the directions of cancer therapy ***,this strategy requires precise information about how the drug interacts with the applied *** this study,atomic force microscopy combined with infrared spectroscopy(AFm-IR)was used for the first time to investigate the erlotinib adsorption structure on two different types of 15 nm metal nanoparticle mono-layers,namely,silver nanoparticle(AgNP)and gold nanoparticle(AuNP)*** the metal nanoparticles are loosely bound samples,only the tapping AFm-IR mode is suitable for the collection of IR maps and spectra for such a *** obtained results indicated the relevance of the AFm-IR technique for characterizing drug interactions with a metal mono-layer *** investigated drug interacts with the AgNPs mainly through phenyl rings and methoxy moieties,while quinazoline,amino,and ethoxy moieties appear to be farther from the *** the AuNPs,the interaction occurs through both the phenyl ring and the quinazoline ***,the aliphatic groups of erlotinib directly participate in this *** novelty of the present work is also related to the use of the tapping AFm-IR mode to study metal NP mono-layers with a drug adsorbed on *** collected IR maps for the most enhanced erlotinib bands show specific areas with very high signal *** connection between these areas and the"hot spots"typical for the surface plasmon resonance phenomenon of metals is considered.

关键词： metal nanoparticle mono-layer drug's adsorption infrared nanospectroscopy atomic force microscopy erlotinib

Tripolye mega-Sites:“Collective Computational Abilities”of Prehistoric Proto-Urban Societies?

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Journal of Social Computing 2022年第1期3卷 75-90页

作者： Johannes müller Robert Hofmann mila Shatilo the Institute of Prehistoric and Protohistoric Archaeology Kiel UniversityKiel 24106Germany

In the East European region between Prut and Dnieper,proto-urban mega-sites developed ca.4100−3600 BCE with population agglomerations of around 10000 inhabitants per *** outline of complexity categories,based on *** et al.(2018),illustrates that“computational abilities”are first developed to make the shift from dispersed to agglomerated settlement *** development of an internal decision-making system for a polity that organizes communication via public buildings on different levels,together with a site-specific track system,may be responsible for this shift(or made it possible).However,after generations,this communication pattern was not developed into further collective communication abilities(e.g.,into a writing system),while at the same time a tendency toward centralizing decision processes probably destroyed the communication *** ultimately led to the collapse of Tripolye mega-sites.

关键词： non-state societies social constitution Chalcolithic mega-sites Tripolye

Analyzing voting power in decentralized governance:Who controls DAOs?

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Blockchain(Research and Applications) 2024年第3期5卷 123-129页

作者： Robin Fritsch marino müller Roger Wattenhofer ETH Zurich 8092ZurichSwitzerland

We empirically study the state of three prominent DAO governance systems on the Ethereum blockchain:Compound,Uniswap and Ethereum name service(ENS).In particular,we examine how the voting power is distributed in these *** a comprehensive dataset of all governance token holders,delegates,propos-als,and votes,we analyze who holds the voting power and how this power is being used to influence governance *** we reveal that the majority of voting power is concentrated in the hands of a small number of addresses,we rarely observe these powerful entities overturning a vote by choosing a different outcome than that of the overall community and less influential voters.

关键词： Decentralized autonomous organization DAO governance Liquid democracy Blockchain

Echo-enhanced ultrasound with pulse inversion imaging: A new imaging modality for the differentiation of cystic pancreatic tumours

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World Journal of Gastroenterology 2006年第14期12卷 2205-2208页

作者： Steffen Rickes Klaus mnkemüller Peter malfertheiner Department of Gastroenterology Hepatology and Infectious Diseases Otto-von-Guericke-UniversityMagdeburgGermany

AIm： To describe and discuss echo-enhanced sonography in the differential diagnosis of cystic pancreatic lesions. mETHODS： The pulse inversion technique （with intravenous injection of 2.4 mL SonoVue） or the power-Doppler mode under the conditions of the 2^nd harmonic imaging （with intravenous injection of 4 g Levovist） was used for echo-enhanced sonography. RESULTS： Cystadenomas frequently showed many vessels along fibrotic strands. On the other hand, cystadenocarcinomas were poorly and chaotically vascularized. ＂Young pseudocysts＂ were frequently found to have a highly vascularised wall. However, the wall of the ＂old pseudocysts＂ was poorly vascularized. Data from prospective studies demonstrated that based on these imaging criteria the sensitivities and specificities of echoenhanced sonography in the differentiation of cystic pancreatic masses were 〉 90%. CONCLUSION： Cystic pancreatic masses have a different vascularization pattern at echo-enhanced sonography. These characteristics are useful for their differential diagnosis, but histology is still the gold standard.

关键词： Cystic pancreatic lesions Differentia diagnosis Echo-enhanced sonography