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TRADE DEPENDENCIES AND TRANSACTION COSTS: THE OC-CUPATION OF DECELEA HIGHLIGHTS BOTH THE BENEFITS AND THE DRAWBACKS OF A MARITIME ECONOMY

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Journal of Ancient Civilizations 2024年第1期39卷 29-50,123页

作者： pascal Warnking Trier University and LEIZA

Thucydides asserts that the occupation of Decelea by the Spartans in 413 BC made the grain supply for Athens costly by forcing the transport from land onto the *** calls into question the well-established consensus that sea transport was far cheaper than land *** paper contends that the cost of protecting supply lines-specifically the expenses associated with the warships which escorted the supply ships-rendered the grain transported on the new route exceptionally *** this paper,the benefits and drawbacks of a maritime economy,including transaction costs,trade dependencies,and the capabilities of warships and supply ships are discussed.

关键词： convoy Decelea maritime dependencies maritime economy sea routes shipping costs transaction costs

An inverse method for characterization of dynamic response of 2D structures under stochastic conditions

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Chinese Journal of Aeronautics 2024年第3期37卷 440-455页

作者： Xuefeng LI Abdelmalek ZINE Mohamed ICHCHOU Noureddine BOUHADDI pascal FOSSAT Laboratory of Tribology and Systems Dynamic Central School of LyonEcully 69134France Institut Camille Jordan Central School of LyonEcully 69134France Department of Applied Mechanics University of Burgundy Franche-ComtéBesancon 25000France

The reliable estimation of the wavenumber space(k-space)of the plates remains a longterm concern for acoustic modeling and structural dynamic behavior *** current analyses of wavenumber identification methods are based on the deterministic *** this end,an inverse method is proposed for identifying wave propagation characteristics of twodimensional structures under stochastic conditions,such as wavenumber space,dispersion curves,and band *** proposed method is developed based on an algebraic identification scheme in the polar coordinate system framework,thus named Algebraic K-Space Identification(AKSI)***,a model order estimation strategy and a wavenumber filter are proposed to ensure that AKSI is successfully *** main benefit of AKSI is that it is a reliable and fast method under four stochastic conditions:(A)High level of signal noise;(B)Small perturbation caused by uncertainties in measurement points’coordinates;(C)Non-periodic sampling;(D)Unknown structural *** validate the proposed method,we numerically benchmark AKSI and three other inverse methods to extract dispersion curves on three plates under stochastic *** experiment is then performed on an isotropic steel *** investigations demonstrate that AKSI is a good in-situ k-space estimator under stochastic conditions.

关键词： Inverse method Dispersion relation Wavenumber space Periodic plates Stochastic conditions Wave propagation characterization

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On-the-fly precision spectroscopy with a dual-modulated tunable diode laser and Hz-level referencing to a cavity

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Advanced Photonics 2024年第4期6卷 36-44页

作者： Shuangyou Zhang Toby Bi pascal Del’Haye Max Planck Institute for the Science of Light Friedrich-Alexander Universit?t Erlangen-Nürnberg Department of Physics

Advances in laser spectroscopy have enabled many scientific breakthroughs in physics, chemistry,biology, and astronomy. Optical frequency combs pushed measurement limits with ultrahigh-frequency accuracy and fast-measurement speed, while tunable-diode-laser spectroscopy is used in scenarios that require high power and continuous spectral coverage. Despite these advantages of tunable-diode-laser spectroscopy, it is challenging to precisely determine the instantaneous laser frequency because of fluctuations in the scan speed. Here, we demonstrate a simple spectroscopy scheme with a frequencymodulated diode laser that references the laser on-the-fly to a fiber cavity. The fiber cavity's free spectral range is on-the-fly calibrated with sub-10-Hz frequency precision. We achieve a relative precision of the laser frequency of 2 × 10-8for an 11-THz frequency range at a measurement speed of 1 THz∕s. This is an improvement of more than 2 orders of magnitude compared to existing diode-laser-spectroscopy *** scheme provides precise frequency calibration markers, while simultaneously tracking the instantaneous scan speed of the laser. We demonstrate the versatility of our method through various applications, including dispersion measurement of a fiber, ultrahigh-Q microresonators, and spectroscopy of a hydrogen fluoride gas cell. The simplicity, robustness, and low cost of this spectroscopy scheme are valuable for out-of-the-lab applications like lidar and environmental monitoring.

关键词： frequency comb gas spectroscopy integrated photonics radio-frequency modulation tunable laser spectroscopy

Modelling of the variation of granular base materials resilient modulus with material characteristics and humidity conditions

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Journal of Road Engineering 2024年第1期4卷 27-35页

作者： Jean-pascal Bilodeau Erdrick Leandro Perez-Gonzalez Ali Saeidi Departement de Genie Civil et Genie des Eaux Universite LavalQuebecG1V 0A6Canada Departement des Sciences Appliquees Universite du Quebeca ChicoutimiChicoutimiG7H 2B1Canada

This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal *** fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water *** results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity *** adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric *** model shows that the variation of Er values is below10%for fully crushed granular ***,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics.

关键词： Resilient modulus Degree of saturation Humidity conditions Unbound granular materials Pavement base

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Substrate topography as a powerful tool to modify glial cell biology and interactions

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Neural Regeneration Research 2025年第5期20卷 1390-1391页

作者： pascal Achenbach Haktan Altinova Gary A.Brook Institute of Neuropathology RWTH Aachen University Hospital Department of Neurosurgery RWTH Aachen University Hospital Aachen Germany Berlin State Office for Health and Social Affairs(LAGeSo) BerlinGermany

Traumatic injuries to the central nervous system(CNS) result in disruption of the intricate network of axons which connect functionally related neurons that are widely distributed throughout the brain and spinal *** normal conditions,maintenance of this complex system is structurally and functionally supported by astrocytes (ACs)and other glial cells,the processes of which form a framework surrounding neuronal cell bodies,dendrites,axons,and synapses.

关键词： injuries topography system

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Massive abdominal muscle atrophy during prolonged mechanical ventilation: Implications for tracheostomy removal

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Journal of Intensive Medicine 2024年第1期4卷 133-135页

作者： pascal Beuret Florian Michelin Audrey Tientcheu Laurane Chalvet Benedicte Philippon-Jouve Jean-Charles Chakarian Xavier Fabre Service de Réanimation et Soins continus Centre Hospitalier de RoanneRoanneFrance

Introduction Maintaining the functional integrity of respiratory muscles is crucial for critically ill patients to be weaned from mechanical ventilation and decannulated if *** of the diaphragm is frequent in patients under mechanical ventilation and has been associated with a longer duration of weaning.[1,2]Studies on expiratory muscles are *** recent studies demonstrated the feasibility and reproducibility of ultrasound in measuring the thickness of abdominal muscles,[3,4]with one study showing abdominal muscle atrophy in 22%of mechanically ventilated critically ill patients during the first week of mechanical ventilation.[4]

关键词： critically mechanical abdominal

Frequency-Diversified Space-Efficient Radiating Surface Using Convolved Electric and Magnetic Currents for Highly Dense Multiband Antenna-Frontend Integration

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Electromagnetic Science 2024年第1期2卷 63-76页

作者： Amirhossein Askarian pascal Burasa Ke Wu Department of Electrical Engineering Poly-Grames Research CenterPolytechnique MontrealQC H3T1J4Canada

We propose and investigate a methodology based on convolved electric and magnetic currents for the generation of multi-band responses over a space-shared radiating ***,a single wideband antenna operation principle based on inter-leaved dipole and slot modes is studied and analyzed using full-wave simulations followed by a qualitative time domain ***,a 2×2 dual-band radiating unit is conceived and developed by closely arranging single wideband *** this case,multimode resonances are generated in a lower frequency band by a proper convolving and coupling of the magnetic and electric currents realized in the gaps between the antennas and on the surface of the antennas,*** methodology can be deployed repeatedly to build up a self-scalable topology by reusing the electromagnetically(EM)connected radiating surfaces and gaps be-tween the radiating *** to the efficient reuse of the electromagnetic region for the development of multiband radiation,a high aperture-reuse efficiency is ***,as a proof of concept,a 2×4 dual-band array operating in Ku-and Ka-bands is devel-oped and fabricated by a linear arrangement of the two developed radiating *** measurement results show that the proposed antenna array provides impedance and gain bandwidths of 30%and 25.4%in the Ku-band and 10.65%and 8.52%in the Ka-band,respectively.

关键词： Aperture-shared array Aperture-reused efficiency Antenna-frontend integration Dual-band antenna Magneto-electric dipole antenna Multi-mode resonance Multi-band array Multi-functional antenna Wideband antenna array

Characteristics of Gold Mineralization at the Baguiomo Gold Panning Site, Koudougou Region, Burkina Faso, West Africa

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Open Journal of Geology 2024年第1期14卷 1-18页

作者： pascal Ouiya Aziz Fayçal Tarnagda Martial Eric Fozing Ecole Normale Supérieure (ENS) Institut Sciences et Technologie (IST) Ouagadougou Burkina Faso Laboratoire Géosciences et Environnement (LaGE) Earth Sciences Department Ouagadougou Burkina Faso Department of Geology University of Dschang Dschang Cameroon

The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are located in the Kwademen-Baguiomo shear zone. This mineralization, located only a few kilometers from the Kwademen gold deposit, is uncharacterized and, together with the latter, could constitute a gold potential capable of being economically exploitable. It is in this sense that this work is carried out with a view to characterizing the gold mineralization of the Baguiomo gold panning site. To carry out this work, we have made direct field measurements, combined with microstructures, and combined all this with data from geochemical rock analysis of the basalts that are the main host formations. Geochemical data show that tholeitic basalts formed from a mantle plume that was emplaced in an oceanic plateau context. Calc-alkaline basalts and andesites are comparable to Paleoproterozoic tholeitic basalts (PTH3), which are slightly enriched in light rare earths. Fertility tests show that these basalts concentrate between 3 and 6 ppb of gold at the time of accretion, which is sufficient for remobilization of this primary gold during the Eburnian orogeny to yield a deposit of around 4 - 5 Moz. Gold mineralization is associated with pyrite crystals when the latter are disseminated in the rock mass, whereas it is associated with hematite in quartz veins concordant with S1 shear deformation. It is mainly the pyrite crystals in the pressure shadows that contain the gold grains, whose development would be synchronous with micro-shear zone reactivation during the first phase of D1B deformation. The second phase of D2B deformation, which is a crenulation or fracture schistosity, does not significantly affect the shear deformation that controls mineralization.

关键词： Kwademen-Baguiomo Shear Zone Gold Panning Site Gold Mineralization Eburnian Orogeny

On-Surface Synthesis of Anthracene-Fused Zigzag Graphene Nanoribbons from 2,7-Dibromo-9,9′-bianthryl Reveals Unexpected Ring Rearrangements

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Precision Chemistry 2024年第2期2卷 81-87页

作者： Xiushang Xu Amogh Kinikar Marco Di Giovannantonio Carlo A.Pignedoli pascal Ruffieux Klaus Müllen Roman Fasel Akimitsu Narita Max Planck Institute for Polymer Research 55128 MainzGermany Organic and Carbon Nanomaterials Unit Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0495Japan Empa Swiss Federal Laboratories for Materials Science and Technologynanotech@surfaces Laboratory8600 DübendorfSwitzerland Institute of Structure of Matter-CNR(ISM-CNR) 00133 RomaItaly Institute of Physical Chemistry Johannes Gutenberg University Mainz55128 MainzGermany Department of Chemistry Biochemistry and Pharmaceutical SciencesUniversity of Bern3012 BernSwitzerland

On-surface synthesis has emerged as a powerful strategy to fabricate unprecedented forms of atomically precise graphene nanoribbons(GNRs).However,the on-surface synthesis of zigzag GNRs(ZGNR)has met with only limited ***,we report the synthesis and on-surface reactions of 2,7-dibromo-9,9′-bianthryl as the precursor towardπ-extended *** by scanning tunneling microscopy and high-resolution noncontact atomic force microscopy clearly demonstrated the formation of anthracene-fused *** skeletal rearrangements were also observed,which could be explained by intramolecular Diels-Alder *** calculations of the electronic properties of the anthracene-fused ZGNRs revealed spin-polarized edge-states and a narrow bandgap of 0.20 eV.

关键词： On-surface synthesis Graphene nanoribbon On-surface reaction Rearrangement Edge state