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An experimental study of elastic properties of dragonfly-like flapping wings for use in biomimetic micro air vehicles(BMAVs)

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chinese Journal of Aeronautics 2017年第2期30卷 726-737页

作者： Praveena Nair Sivasankaran Thomas Arthur Ward Erfan Salami Rubentheren Viyapuri christopher J.Fearday Mohd Rafie johan department of Mechanical Engineering University of Malaya KuaIa Lumpur 50603 Malaysia School of Engineering and Physical Sciences Heriot-Watt University Malaysia Putrajaya 62200 Malaysia department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia

This article studies the elastic properties of several biomimetic micro air vehicle（BMAV）wings that are based on a dragonfly *** are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms（e.g.,insects,birds,and bats）.Three structurally identical wings were fabricated using different materials：acrylonitrile butadiene styrene（ABS）,polylactic acid（PLA）,and *** wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual *** wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10-250 Hz.A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels x 240 pixels and 35000 frames per *** maximum bending angle,maximum wing tip deflection,maximum wing tip twist angle,and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly *** results show that the ABS wing has considerable flexibility in the chordwise direction,whereas the PLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise *** studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is ***,the ABS wing（fabricated using a 3D printer） shows the most promising results for future applications.

关键词： ABS Acrylic Biomimetic micro air vehicle Flapping mechanism PLA Wing structure

Mitigation of Mycotoxins during Food Processing:Sharing Experience among Europe and South East Asia

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粮油食品科技 2021年第6期29卷 59-70页

作者： Paula Alvito Jonathan Barcelo johan de Meester Elias Rito Michele Suman Food and Nutrition department National Institute of Health Dr.Ricardo JorgeAvenida Padre Cruz1649-016 LisboaPortugal cESAM Centre for Environmental and Marine StudiesUniversity of AveiroCampus Universitário de Santiago3810-193 AveiroPortugal School of Natural Sciences Saint Louis UniversityBonifacio StreetBaguio CityPhilippines cargill R&D centre Europe Havenstraat 84B-1800 VilvoordeBelgium European Association of chemical Distributors Rue du Luxembourg16B 1000 BrusselsBelgium Barilla SpA-Advanced Research Laboratory via Mantova 166-43122 ParmaItaly

Worldwide the issue of mycotoxins results in economic losses estimated at billions of dollars and toxicological risk for both humans and *** measures also include decontamination and mitigation actions that can be carried out through food *** proposals have been tested and illustrated also in scientific papers during the last dec.des,however clear,easy to implement,practical suggestions and guidelines for process adaptation are much more *** and South East Asia can find synergies and complementarities moving from processing to analysis,from risk assessment to reduction strategies,from gap-analysis to communication *** from both Europe and Southeast Asia must then ensure that there is a way to ease and harmonize the regulation in the food supply chain in order to ensure food safety and at the same time facilitate trade in both regions,taking into account of the various landscapes,agrosystems and also different consumer preferences within the countries *** the example of cereals,processing steps cover primary processing(cleaning and milling operations)and secondary processing procedures(such as fermentation and thermal treatments during baking),special attention is devoted to the production of baked goods and to the estimation of processing factors for DON in wheat bread production especially in *** reference instead to the specific context of Asian producers,a case-study focuses on ochratoxin A in coffee in Southeast Asia region,combining the expertise of the farming community,coffee industry and science *** strategy to reduce mycotoxins in a farm setting poses several challenges to coffee farmers:it needs to be analyzed in the context of good agricultural practices,socioeconomic and behavioral factors of both coffee producers and *** the world becomes more globalized,food and feed supply chains also become more complexed and hence,a more comprehensive strategy to

关键词： mitigation food processing mycotoxins cereals coffee Europe South East Asia

Photochemical smog in china:scientific challenges and implications for air-quality policies

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National Science Review 2016年第4期3卷 401-403页

作者： Mattias Hallquist John Munthe Min Hu Tao Wang chak K chan Jian Gao johan Boman Song Guo ?sa M Hallquist johan Mellqvist Jana Moldanova Ravi K Pathak Jan Bc Pettersson H?kan Pleijel David Simpson Marie Thynell department of chemistry and Molecular Biology University of Gothenburg IVL Swedish Environmental Research Institute State Key Joint Laboratory of Environmental Simulation and Pollution control College of Environmental Sciences and EngineeringPeking University department of civil and Environmental Engineering the Hong Kong Polytechnic University School of Energy and Environment City University of Hong Kong chinese Research Ac.demy of Environmental Sciences collaborative Innovation center of Atmospheric Environment and Equipment Technology Earth and Space Sciences Chalmers University of Technology department of Biological and Environmental Sciences University of Gothenburg Norwegian Meteorological Institute School of Global Studies University of Gothenburg

INTRODUcTION Severe air-pollution events in many parts of china pose a major threat to health and ecosystems[1].china’s air pollution is concentrated to economically developed areas,such as Beijing–Tianjin–Hebei(BT... 详细信息

关键词： Photochemical smog in china SOA OOA

Reassessment of historical sections from the Paleogene marine margin of the congo Basin reveals an almost complete absence of Danian deposits

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Geoscience Frontiers 2019年第3期10卷 1039-1063页

作者： Floréal Solé corentin Noiret delphine desmares Sylvain Adnet Louis Taverne Thierry de Putter Florias Mees johan Yans Thomas Steeman Stephen Louwye Annelise Folie Nancy J.Stevens Gregg F.Gunnell Daniel Baudet Nicole Kitambala Yaya Thierry Smith Royal Belgian Institute of Natural Sciences (RBINS) Operational Directorate Earth and History of Life University of Namur (UNamur) Department of Geology Rue de Bruxelles 61 Sorbonne Université UPMC Paris 06 UMR 7207 (CR2P) UMR 5554-Institut des Sciences de l'Evolution Université Montpellier Place E.Bataillon Royal Museum for central Africa (RMcA) Geodynamics and Mineral Resources Leuvensesteenweg 13 Ghent University (UGent) Department of Geology Royal Belgian Institute of Natural Sciences (RBINS) Heritage Scientific Survey Ohio University Department of Biomedical Sciences Heritage College of Osteopathic Medicine Duke University Lemur center Division of Fossil Primates (DFP) centre de Recherches Géologiques et Minières (cRGM) 44 av.de la Démocratie Kinshasa Gombe

The early Paleogene is critical for understanding global biodiversity patterns in modern ecosystems. During this interval, Southern Hemisphere continents were largely characterized by isolation and faunal endemism following the breakup of Gondwana. Africa has been proposed as an important source area for the origin of several marine vertebrate groups but its Paleogene record is poorly sampled, especially from sub-Saharan Africa. To document the early Paleogene marine ecosystems of central Africa, we revised the stratigraphic context of sedimentary deposits from three fossil-rich vertebrate localities: the Landana section in the cabinda exclave(Angola), and the Manzadi and Bololo localities in western democratic Republic of *** provide more refined age constraints for these three localities based on invertebrate and vertebrate faunas, foraminiferal and dinoflagellate cyst assemblages, and carbon isotope records. We find an almost complete absence of Danian-aged rocks in the Landana section, contrary to prevailing interpretations over the last half a century(only the layer 1, at the base of the section, seems to be Danian). Refining the age of these Paleocene layers is crucial for analyzing fish evolution in a global framework, with implications for the early appearance of Scombridae(tunas and mackerels) and Tetraodontiformes(puffer fishes). The combination of vertebrate fossil records from Manzadi and Landana sections suggests important environmental changes around the K/Pg transition characterized by an important modification of the ichthyofauna. A small faunal shift may have occurred during the Selandian. More dramatic is the distinct decrease in overall richness that lasts from the Selandian to the Ypresian. The Lutetian of West central Africa is characterized by the first appearance of numerous cartilaginous and bony fishes. Our analysis of the ichthyofauna moreover indicates two periods of faunal exchanges: one during the Paleocene, where central Africa app

关键词： central Africa Paleogene Stratigraphy carbon isotope Planktonic foraminifera Vertebrates

Observation of a single protein by ultrafast X-ray diffraction

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Light(Science & Applications) 2024年第1期13卷 80-90页

作者： Tomas Ekeberg Dameli Assalauova johan Bielecki Rebecca Boll Benedikt J.Daurer Lutz A.Eichacker Linda E.Franken Davide E.Galli Luca Gelisio Lars Gumprecht Laura H.Gunn Janos Hajdu Robert Hartmann Dirk Hasse Alexandr Ignatenko Jayanath Koliyadu Olena Kulyk Ruslan Kurta Markus Kuster Wolfgang Lugmayr Jannik Lübke Adrian P.Mancuso Tommaso Mazza carl Nettelblad Yevheniy Ovcharenko Daniel E.Rivas Max Rose Amit K.Samanta Philipp Schmidt Egor Sobolev Nicusor Timneanu Sergey Usenko Daniel Westphal Tamme Wollweber Lena Worbs Paul Lourdu Xavier Hazem Yousef Kartik Ayyer Henry N.chapman Jonas A.Sellberg carolin Seuring Ivan A.Vartanyants Jochen Küpper Michael Meyer Filipe R.N.c.Maia Laboratory of Molecular Biophysics Department of Cell and Molecular BiologyUppsala UniversityHusargatan 3(Box 596)SE-75124 UppsalaSweden deutsches Electronen-Synchrotron deSY Notkestrasse 8522607 HamburgGermany European XFEL Holzkoppel 422869 SchenefeldGermany Diamond Light Source Harwell Science&Innovation CampusDidcot OX110DEUK University of Stavanger Centre Organelle ResearchRichard-Johnsensgate 44021 StavangerNorway Leibniz Institute for Experimental Virology(HPI) Centre for Structural Systems BiologyNotkestraße 8522607 HamburgGermany Dipartimento di Fisica“Aldo Pontremoli” Universitàdegli Studi di Milanovia Celoria 1620133 MilanoItaly center for Free-Electron Laser Science DESY22607 HamburgGermany Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA PNSensor GmbH Otto-Hahn-Ring 6D-81739 MünchenGermany Biomedical and X-Ray Physics Department of Applied PhysicsAlbaNova University CenterKTH Royal Institute of TechnologySE-10691 StockholmSweden ELI Beamlines/IoP Institute of Physics AS cR v.v.i.Na Slovance 218221 Prague 8Czech Republic Multi-User cryoEM Facility Centre for Structural Systems BiologyNotkestr.8522607 HamburgGermany University Medical center Hamburg-Eppendorf(UKE) Martinistrasse 5220246 HamburgGermany The Hamburg center for Ultrafast Imaging Universität HamburgLuruper Chaussee 14922761 HamburgGermany department of Physics Universität HamburgLuruper Chaussee 14922761 HamburgGermany department of chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe UniversityMelbourneVIC 3086Australia Division of Scientific computing Science for Life LaboratoryDepartment of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden European Molecular Biology Laboratory c/o DESYNotkestrasse 8522607 HamburgGermany department of Physics and Astronomy Uppsala UniversityBox 516SE-75120 UppsalaSweden Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 14922761 HamburgGe

The idea of using ultrashort X-ray pulses to obtain images of single proteins frozen in time has fascinated and inspired *** was one of the arguments for building X-ray free-electron *** to theory,the extremely intense pulses provide sufficient signal to dispense with using crystals as an amplifier,and the ultrashort pulse duration permits capturing the diffraction data before the sample inevitably *** was first demonstrated on biological samples a dec.de ago on the giant *** then,a large collaboration has been pushing the limit of the smallest sample that can be *** ability to capture snapshots on the timescale of atomic vibrations,while keeping the sample at room temperature,may allow probing the entire conformational phase space of *** we show the first observation of an X-ray diffraction pattern from a single protein,that of Escherichia coli GroEL which at 14 nm in diameter is the smallest biological sample ever imaged by X-rays,and demonstrate that the concept of diffraction before destruction extends to single *** the pattern,it is possible to determine the approximate orientation of the *** experiment demonstrates the feasibility of ultrafast imaging of single proteins,opening the way to single-molecule time-resolved studies on the femtosecond timescale.

关键词： smallest intense ultrafast

cancer risk and mortality in patients with solitary Peutz–Jeghers polyps

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Gastroenterology Report 2023年第1期11卷 576-578页

作者： Anne Marie Jelsig Laus Wullum Lilian Bomme Ousager johan Burish Tine Plato Kuhlmann John Gasdal Karstensen department of clinical Genetics University Hospital of CopenhagenRigshospitaletCopenhagenDenmark Omicron Aps CopenhagenDenmark department of clinical Genetics Odense University HospitalOdenseDenmark Human Genetics Institute of Clinical ResearchUniversity of Southern DenmarkOdenseDenmark Gastrounit Medical DivisionCopenhagen University Hospital—Amager and HvidovreHvidovreDenmark department of Pathology Copenhagen University HospitalHerlevDenmark department of clinical Medicine University of CopenhagenCopenhagenDenmark Danish Polyposis Registry GastrounitCopenhagen University Hospital—Amager and HvidovreHvidovreDenmark

Introduction Solitary Peutz–Jeghers polyps are hamartomatous lesions in the gastrointestinal(GI)*** are rare and can be diagnosed in both children and adults(Figure 1A).Microscopically,Peutz–Jeghers polyps can have ... 详细信息

关键词： Jeghers Peutz polyps

Transfer learning in demand response: A review of algorithms for data-efficient modelling and control

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能源与人工智能(英文) 2022年第1期7卷 183-196页

作者： Thijs Peirelinck Hussain Kazmi Brida V.Mbuwir chris Hermans Fred Spiessens johan Suykens Geert deconinck ESAT KU LeuvenKasteelpark Arenberg 10 bus 24453001 LeuvenBelgium AMO Flemish Institute for Technological Research(VITO)Boeretang 2002400 MolBelgium AMO EnergyVilleThor Park 83103600 GenkBelgium

A number of decarbonization scenarios for the energy sector are built on simultaneous electrification of energy demand,and decarbonization of electricity generation through renewable energy ***,increased electricity demand due to heat and transport electrification and the variability associated with renewables have the potential to disrupt stable electric grid *** address these issues using demand response,researchers and practitioners have increasingly turned towards automated decision support tools which utilize machine learning and optimization ***,when applied naively,these algorithms suffer from high sample complexity,which means that it is often impractical to fit sufficiently complex models because of a lack of observed *** advances have shown that techniques such as transfer learning can address this problem and improve their performance considerably—both in supervised and reinforcement learning *** formulations allow models to leverage existing domain knowledge and human expertise in addition to sparse observational *** formally,transfer learning embodies all techniques where one aims to increase(learning)performance in a target domain or task,by using knowledge gained in a source domain or *** paper provides a detailed overview of state-of-the-art techniques on applying transfer learning in demand response,showing improvements that can exceed 30%in a variety of *** observe that most research to date has focused on transfer learning in the context of electricity demand prediction,although reinforcement learning based controllers have also seen increasing ***,a number of limitations remain in these studies,including a lack of benchmarks,systematic performance improvement tracking,and consensus on techniques that can help avoid negative transfer.

关键词： demand response Transfer learning Reinforcement learning Review Smart grid

Selective ligninolysis of wheat straw and wood chips by the white-rot fungus Lentinula edodes and its influence on in vitro rumen degradability

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Journal of Animal Science and Biotechnology 2017年第2期8卷 391-404页

作者： Sandra J.A.van Kuijk José c.del Río Jorge Rencoret Ana Gutiérrez Anton S.M.Sonnenberg johan J.P.Baars Wouter H.Hendriks John W.cone Animal Nutrition Group Wageningen UniversityDe Elst 16708 WD WageningenThe Netherlands Instituto de Recursos Naturales y Agrobiologica de Sevilla(IRNAS-cSIc) Avenida Reina Mercedes1042012 SevilleSpain Plant Breeding Wageningen UniversityDroevendaalsesteeg 16708 PB WageningenThe Netherlands

Background： The present work investigated the influence of lignin content and composition in the fungal treatment of lignocellulosic biomass in order to improve rumen degradability. Wheat straw and wood chips,differing in lignin composition, were treated with Lentinula edodes for 0, 2, 4, 8 and 12 wk and the changes occurring during fungal degradation were analyzed using pyrolysis-gas chromatography-mass spectrometry and detergent fiber ***： L. edodes preferentially degraded lignin, with only limited cellulose degradation, in wheat straw and wood chips, leaving a substrate enriched in cellulose. Syringyl（S）-lignin units were preferentially degraded than guaiacyl（G）-lignin units, resulting in a decreased S/G ratio. A decreasing S/G ratio（wheat straw： r =-0.72, wood chips： r =-0.75） and selective lignin degradation（wheat straw： r =-0.69, wood chips： r =-0.88） were correlated with in vitro gas production（IVGP）, a good indicator for rumen ***： L. edodes treatment increased the IVGP of wheat straw and wood chips. Effects on IVGP were similar for wheat straw and wood chips indicating that lignin content and 3D-structure of cell walls influence in vitro rumen degradability more than lignin composition.

关键词： Fungal treatment In vitro rumen degradability Lignocellulosic biomass Py-Gc/MS

Positive effect of spring advance on the diet quality of an alpine herbivore

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Integrative Zoology 2022年第1期17卷 78-92页

作者： johan ESPUNYES Emmanuel SERRANO Sara cHAVES Jordi BARTOLOMÉ Pierre MENAUT Elena ALBANELL Pascal MARcHAND Kévin FOULcHÉ Mathieu GAREL Wildlife Ecology and Health group(WE&H)i Servei d’Ecopatologia de la Fauna Salvatge(SEFaS) Department of Animal Medicine and SurgeryFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain Wildlife conservation Medicine Research Group(WildcoM) Department of Animal Medicine and SurgeryFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain Research and conservation department Zoo de BarcelonaBarcelonaSpain Group of Ruminant Research(G2R) Department of Animal and Food ScienceFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain French Agency for Biodiversity Direction Régionale OccitanieService d’Appui aux Acteurs et Mobilisation du TerritoireVilleneuve de RivièreFrance French Agency for Biodiversity Direction de la Recherche et Appui ScientifiqueUnitéOngulés SauvagesGièresFrance

changes in vegetation phenology related to global warming are having alarming effects on the life history traits of many herbivore *** changes are particularly critical in alpine ecosystems,where strong climate limitations on plant growth make seasonal synchronization imperative for the growth,reproduction and survival of ***,despite the pivotal role of resource-use strategies on the performances of such species,few studies have explicitly assessed the mechanistic impact of climate change on their *** aimed to fill this gap by studying the effect of spring onset on the dietary composition and quality of a medium-size alpine herbivore while considering density-dependent processes and age-and sex-specific differences in foraging *** an exceptional,long-term(24 years)direct individual-based dietary monitoring of a Pyrenean chamois population(Rupicapra pyrenaica pyrenaica),we showed that ongoing earlier onsets of spring are leading to an earlier access to high-quality forage and therefore a higher diet quality at a fixed date,without apparent changes in diet *** also showed that at high densities,intraspecific competition reduced diet quality by driving animals to feed more on woody plants and less on nutritious forbs and *** assessing the mechanistic effects of global warming on the dietary patterns of species at the center of trophic networks,this study is an essential step for predictive models aiming at understanding the ongoing ecosystem consequences of the global climatic crisis.

关键词： cuticle microhistological analysis diet composition near-infrared spectroscopy Rupicapra pyrenaica