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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 sea.This calls into question the well-established consensus that sea transport was far cheaper than land transport.This 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 costly.In 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 characterization.Most current analyses of wavenumber identification methods are based on the deterministic hypothesis.To 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 gaps.The proposed method is developed based on an algebraic identification scheme in the polar coordinate system framework,thus named Algebraic K-Space Identification(AKSI)technique.Additionally,a model order estimation strategy and a wavenumber filter are proposed to ensure that AKSI is successfully applied.The 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 periodicity.To validate the proposed method,we numerically benchmark AKSI and three other inverse methods to extract dispersion curves on three plates under stochastic conditions.One experiment is then performed on an isotropic steel plate.These 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

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 analyses.The fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water content.The 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 decreases.An 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 properties.The model shows that the variation of Er values is below10%for fully crushed granular materials.However,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

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 tracheotomized.Dysfunction 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 scarce.Two 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

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卫星高光谱红外大气探测的正演模拟研究

红外与毫米波学报 2005年第6期24卷 414-418页

作者：张鹏 pascal brunel 董超华张文建中国气象局国家卫星气象中心 Centre de Meteorologie Spatiale/Meteo-France Lannion/France22302

利用精确的红外大气辐射传输计算模型KCARTA,模拟计算了光谱分辨率、通道光谱响应函数、光谱定标精度、大气倾斜路径和表面发射率对高光谱观测亮温的影响.正演计算的结果表明:1)提高光谱分辨率明显增加了可探测的大气亮温;2)各种内、外... 详细信息

利用精确的红外大气辐射传输计算模型KCARTA,模拟计算了光谱分辨率、通道光谱响应函数、光谱定标精度、大气倾斜路径和表面发射率对高光谱观测亮温的影响.正演计算的结果表明:1)提高光谱分辨率明显增加了可探测的大气亮温;2)各种内、外部因素的变化对高光谱仪器将产生远较低光谱仪器更大的观测亮温差.本研究可为我国高光谱大气探测仪器的设计以及高光谱大气探测反演算法研究的开展提供科学的参考依据.

关键词：卫星红外高光谱大气探测正演模拟

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 HospitalAachenGermany

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 cord.Under 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

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

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Journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： Tim Böttrich pascal Bauer Vincent Gröβer Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski Franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten Krüger Christopher Weyh Department of Exercise Physiology and Sports Therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany TH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular disease.Since pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early interventions.There is evidence that regulatory T cells(Tregs)are involved in the development of atherosclerosis.Therefore,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated signatures.Methods:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking medication.Ultrasound of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were performed.Additionally,tests were conducted to assess blood lipids and determine glucose levels.Immunophenotyping of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow cytometry.Participants were categorized according to atherosclerotic plaque status.Linear and logistic regression models were used to analyze associations between parameters.Results:SAP was detected in a total of 29 participants.The participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and mTregs(OR=1.05(95%CI:1.021.10))as independent

关键词： Cardiorespiratory fitness Elderly Regulatory T cells Subclinical atherosclerosis

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

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 success.Herein,we report the synthesis and on-surface reactions of 2,7-dibromo-9,9′-bianthryl as the precursor towardπ-extended ZGNRs.Characterization by scanning tunneling microscopy and high-resolution noncontact atomic force microscopy clearly demonstrated the formation of anthracene-fused ZGNRs.Unique skeletal rearrangements were also observed,which could be explained by intramolecular Diels-Alder cycloaddition.Theoretical 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

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 surface.First,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 analysis.Subsequently,a 2×2 dual-band radiating unit is conceived and developed by closely arranging single wideband antennas.In 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,respectively.This 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 units.Due to the efficient reuse of the electromagnetic region for the development of multiband radiation,a high aperture-reuse efficiency is achieved.Finally,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 units.Our 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