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Bio-inspired Topological Skeleton for the Analysis of Quadruped Kinematic Gait

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Journal of Bionic Engineering 2018年第5期15卷 839-850页

作者： Benjamin Boudon Jean-Marc Linares Anick Abourachid Arthur Vauquelin Emmanuel Mermoz Aix Marseille University CNRS ISM Marseille 13009 France Museum National d'Histoire Naturelle Pavillon d'Anatomie Comparbe 57 rue Cuvier F-75231 Paris Cedex 05 France Airbus Helicopters Abroport de Marseille Provence Marignane 13700 France

In bio-inspired design activities, nature is a basis of knowledge. Over the last twenty years, many solutions to measure and analyze human or animal gaits have been developed （VICON system, X-ray radiography...）. Although, these methods are becoming more and more accurate, they are quite expensive, long to set up and not easily portable. In this paper, a method called the bio-inspired topological skeleton is proposed in order to complement the classic videography process and to enable animal gait analysis. A new predictive kinematic model with closed-loops of an unguligrade quadruped is suggested. This kinematic model includes three segments per leg and takes into account the scapula movements. The proposed method allows us to improve the accuracy of the kinematic input data measured from a single video including an additional artefact. To show the benefits of this method, joint parameters that are difficult to measure are derived symbolically from the kinematic model and compared with experimental data.

关键词： quadruped locomotion motion analysis topological skeleton closed-form solutions Multibody Systems (MBS)

Sol-Gel Relative Humidity Sensors: Impact of Electrode Geometry on Performance in Soil Suction Measurements

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Journal of Sensor Technology 2017年第1期7卷 1-23页

作者： Rafaela Cardoso Gabriele Sarapajevaite Oleksandr Korsun Susana Cardoso Laura Ilharco Instituto Superior Técnico (IST) Universidade de Lisboa Lisbon Portugal Civil Engineering Research Innovation and Sustainability (CERIS) Institute of Construction Structures and Territory of IST (ICIST) Lisbon Portugal INESC-MN Microsystems and Nanotechnologies Lisbon Portugal CQfM Centro de Química-física Molecular Instituto Superior Técnico (IST) Lisbon Portugal

This paper describes the experimental procedure followed to fabricate and validate sol-gel based RH sensors which will be incorporated in soil specimens for standard laboratorial tests. It is the first time such sensors were used for soil suction measurement. They are microfabricated relative humidity sensors (footprint area 11,000 μm × 22,000 μm) operating based on changes in electrical resistivity detected by a cerium doped silica titania film deposited using a sol-gel technique. Their design required gathering experts in several engineering specialties. The working principle of the sensors is based on water vapour equilibrium between the air in the soil and in the sol-gel pores, due to the contact between the two porous materials. The spacing between interdigitated aluminium electrodes was optimized to improve the sensing properties of the sol-gel. The calibration of the different prototypes was done against compacted clay, varying the spacing between 100 and 700 μm. The sensors were also incorporated in soil samples for suction measurement during wetting and drying paths. They were validated by comparing the readings with those from a water dew point potentiometer. from this study it was possible to determine the optimum electrodes spacing of 200 μm. Error was explained by sol-gel heterogeneity effect and by the resolution of the sensing area provided by the electrodes spacing. When comparing with other sensors operating inside soil specimens in standard laboratorial tests, these sol-gel sensors extend the operation range available with the alternative technologies: while conventional tensiometers measure suction ranges from 0 to 1.8 MPa, our sensors demonstrate good results between 1 to 10 MPa (and higher).

关键词： Microfabricated Interdigitated Electrodes Humidity Sensors Suction Unsaturated Soils

Visual grading criteria for Japanese larch ( Larix kaempferi ) structural timber from Spain

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Journal of forestry Research 2020年第6期31卷 2605-2614页

作者： Mari-Jose Barriola José-Ramón Aira Edgar Lafuente Tknika LHri Aplikatutako Ikerketa eta Berrikuntzako EAEko zentroaZamalbide Auzoa z/g20100 ErrenteriaGipuzkoaSpain Escuela de Ingeniería de la Industria forestal Agronómica y de la BioenergíaUniversidad de ValladolidUVa-Campus Duques de Sorias/n42005 SoriaSpain Cesefor Centro de Servicios y Promoción Forestal y de su Industria de Castilla y LeónCalle C42005 SoriaSpain

Larch wood is structurally classifi ed in many countries as one of conifers with the highest load-bearing capacity(strength class of C30).The Spanish visual classifi cation regulation only assigns a strength class to 4 pine woods:Laricio pine(Pinus nigra ***),Silvestre pine(Pinus sylvestris L.),Radiata pine(Pinus radiata ***),and Pinaster pine(Pinus pinaster Ait.).This work adds to the number of structurally characterised species by creating a visual classifi cation table for Japanese larch wood(Larix kaempferi(Lamb.)Carr.)which diff erentiates between 2 visual classes,MEG-1 and *** strength values were calculated for each class(fk,MEG-1=31.80 MPa,f k,MEG-2=24.55 MPa),mean module of elasticity(E 0,mean,MEG-1=13,082 MPA,E 0,mean,MEG-2=12,320 MPA)and density(ρk,MEG-1=456.6 kg m−3,ρk,MEG-2=469.1 kg m−3),before fi nally assigning a strength class of C30 to visual class MEG-1,and a strength class of C24 to visual class MEG-2.

关键词： Japanese larch wood Visual grading Strength class Mechanical properties density

High‑throughput sequencing view on the magnitude of global fungal diversity

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fungal Diversity 2022年第3期114卷 539-547页

作者： Petr Baldrian TomášVětrovský Clémentine Lepinay Petr Kohout Laboratory of Environmental Microbiology Institute of Microbiology of the Czech Academy of SciencesVídeňská108314220 Prague 4Czech Republic

High-throughput DNA sequencing has dramatically transformed several areas of biodiversity research including *** limitations,high-throughput sequencing is nowadays a predominant method to characterize the alpha and beta diversity of fungal *** the papers utilizing high-throughput sequencing approaches to study natural habitats in terrestrial ecosystems worldwide,>200 studies published until 2019 have generated over 250 million sequences of the primary mycological metabarcoding marker,the nuclear ribosomal internal transcribed spacer 2(ITS2).Here we show that at a 97%sequence similarity threshold,the total richness of non-singleton fungal taxa across the studies published so far is 1.08 million,mostly Ascomycota(56.8%of the taxa)and Basidiomycota(36.7%of the taxa).The Chao-1 estimate of the total extant fungal diversity based on this dataset is 6.28 million taxa,representing a conservative estimate of global fungal species *** and litter represent the habitats with the highest alpha diversity of fungi followed by air,plant shoots,plant roots and deadwood with Chao-1 predictions,for samples containing 5000 sequences,of 1219,569,392,228,215 and 140 molecular species,*** on the high-throughput sequencing data,the highest proportion of unknown fungal species is associated with samples of lichen and plant *** considering the use of high-throughput sequenc-ing for the estimation of global fungal diversity,the limitations of the method have to be taken into account,some of which are sequencing platform-specific while others are inherent to the metabarcoding approaches of species *** this respect,high-throughput sequencing data can complement fungal diversity predictions based on methods of traditional mycology and increase our understanding of fungal biodiversity.

关键词： High-throughput sequencing Metabarcoding Internal transcribed spacer Alpha diversity Meta-analysis

Queens remate despite traumatic mating in stingless bees

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Current Zoology 2022年第1期68卷 81-92页

作者： Jamille Costa VEIGA Gustavo Rodrigo Sanches RUIZ Gislene Almeida CARVALHO-ZILSE Cristiano MENEZES felipe Andres Leon CONTRERA Bee Biology and Ecology Lab Instituto de Ciencias BiologicasUniversidade Federal do ParaBelem66075-110 ParaBrazil Biodiversity and Ecosystem Services Research Group Instituto Tecnologico Vale-Desenvolvimento SustentavelBelem66055-090 ParaBrazil Ecology and Zoology of Invertebrates Lab Instituto de Ciencias BiologicasUniversidade Federal do ParaBelem66075-110 ParaBrazil Bee Research Group Instituto Nacional de Pesquisas da AmazoniaManaus69067-375 AmazonasBrazil Research and development Embrapa Meio AmbienteJaguariuna13820-000 Sao PauloBrazil

Males can control female reproduction using genital plugs to impede access by *** social bees,ants,and wasps,plugging may involve traumatic mating,with females being *** stingless bees,chances are that plugs may promote ovarian activan,and are thought to ensure single mating—a general tendency among the social ***,understanding on relationships between mating plugs,traumatic mating,and mating systems in stingless bees remains *** address this,we(1)compared mated queens of 7 Neotropical species to understand the patterns of copulatory marks in females and(2)compared pre-and post-mating genitalia of males and females in Melipona fasciculata to depict plug functional *** revealed an unprecedented consequence of mating in stingless bees:the characteristic marks left by mating plugs on female abdomens and the inferences that can be made from *** our surprise,in 1 species *** we found that queens retain the plug long after mating,and may carry it for the rest of their *** the other 6 species retained the plug for only a short *** queens were only found in ***,whose multiple copulatory marks match previous findings of polyandry in this *** study shows that queens can remate,and suggests that male genital morphology may determine in part the time persistence of *** conclude that traumatic mating plugs do not fully prevent remating in stingless bees and that mating systems are not uniform in this ***,exceptional cases of facultative polyandry in social insects—for example,when mating plugs fail—may confirm a general tendency for single mating in close link with efficient mating plugs.

关键词： copulatory marks facultative polyandry genital morphology male harm sexual conflict

Historical relationships of the Mesoamerican highlands,with emphasis on tropical montane cloud forests:a temporal cladistic biogeographical analysis

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Journal of Mountain Science 2023年第1期20卷 129-140页

作者： CASTRO-TORREBLANCA Marisol ESPINOSA David BUENO-HERNANdeZ Alfredo LUNA-VEGA Isolda Biological Sciences Graduate Program Coordination of Graduate StudiesNational Autonomous University of MexicoUniversity CityCoyoacán04510Mexico CityMexico Comparative Biology and Biodiversity Research Unit Facultad de Estudios Superiores ZaragozaNational Autonomous University of MexicoAv.Batalla del 5 de mayo s/nCol.Ejército de Oriente09230Mexico CityMexico Laboratory of Biogeography and Systematics Department of Evolutionary BiologyFaculty of SciencesNational Autonomous University of MexicoUniversity CityCoyoacán04510Mexico CityMexico

The historical relationships of nine areas of endemism of the tropical montane cloud forests(TMCfs)were analysed based on a temporal cladistic biogeographical *** cladistic biogeographical analyses were conducted based on 29cladograms of terrestrial taxa by partitioning them into three time-slices,namely,Miocene,Pliocene,and *** results showed different area relationships over *** the Miocene and Pliocene time slices,the Isthmus of Tehuantepec acted as a geographic barrier that fragmented the TMCfs into two portions:west of the Isthmus and east of the *** the case of the Pleistocene,the TMCfs were broken into two portions,one related to the Neotropical region and the other to the Nearctic ***,the analyses allowed us to detect the influences of different geological and paleoclimatological events on the distribution of the TMCfs over ***,the TMCfs current distribution might have been driven by geological events during the Miocene-Pliocene,whereas climatic fluctuations have the highest impact during the Pleistocene.

关键词： Dispersal Evolutionary biogeography Paralogy free subtree analysis Vicariance

A unified electrical model based on experimental data to describe electrical transport in carbon nanotube-based materials

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Nano Research 2020年第6期13卷 1764-1779页

作者： Yoann Dini Jérôme faure-Vincent Jean Dijon Univ.Grenoble-Alpes CEALITENDTNMF-38000GrenobleFrance Univ.Grenoble-Alpes CEACNRSIRIGSyMMESF-38000GrenobleFrance

Understanding the electrical transport in carbon nanotube(CNT)materials is one key to reach very high electrical *** CNT material resistivity(ρ(T))as function of the temperature are fully apprehended by their reduced activation W(T)=dln(ρ)/dln(T)*** to now,no model accurately fits W(T)curves,thus preventing from precisely describing the CNT material electrical *** present a new electrical transport model that perfectly fits all W(T)curves found in the literature and in our own *** material resistivities are modeled byρ(T)=ρ0(T^−α+M(1+βTγT^2)).Our model has few enough parameters(α,M,β,γ)to relate them to the CNT *** 70 K,we experimentally show that CNT material resistivity follows the Luttinger Liquid theory justifying the T^−αterm in our *** 70 K,the polynomial part becomes dominant and depends on the two different CNT fabrication techniques which lead to two very different yarn *** yarns made from floating catalyst chemical vapor deposition CNTs,the polynomial is explained by the percolation of metallic CNT ***,the polynomial of yarns spun from CNT arrays is explained by the electrical transport in CNT bundles which are the basic building blocks of this type of yarns.

关键词： carbon nanotube carbon-based materials electrical conductivity electrical transport model Luttinger Liquid

Engineering versatile Au-based catalysts for solar-to-fuel conversion

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能源化学:英文版 2023年第8期83卷 341-362,I0010页

作者： Chunhua Wang Hongwen Zhang feili Lai Zhirun Xie Yun Hau Ng Bo Weng Xuejiao Wu Yuhe Liao department of Chemistry KU LeuvenCelestijinenlaan 200F3001 LeuvenBelgium cMACS Department of Microbial and Molecular SystemsKU LeuvenCelestijnenlaan 200F3001 LeuvenBelgium School of Energy and Environment City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong 999077China Centre for Sustainable Catalysis and Engineering Faculty of Bioscience EngineeringKU Leuven3001 LeuvenBelgium Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640GuangdongChina

Gold(Au) nanostructures(NSs) have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials, while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-fuel conversion efficiency is still lacking. In this review, the recently developed strategies for elevating the overall photocatalytic performance of Au-based catalysts and the deep physical chemistry mechanisms are highlighted. firstly, the synthetic approaches of Au NSs are summarized, followed by an elaboration on their multiple functions in improving photoactivity. Afterward, modification strategies of Au NSs used to enhance the photocatalytic efficiency of Au-semiconductor composites,including controlling the Au NSs morphology, size, crystal phase, defect engineering, alloying with different metals, modulating interfacial interaction, and introducing an external field, are summarized and discussed independently. Additionally, advanced characterization techniques that can provide insights into the charge dynamics of the photocatalysts are introduced. finally, we share our opinion on the challenges and outline potentially promising opportunities and directions for efficient Au-based photocatalysis research moving forward. We sincerely look forward to this review can deliver insightful views to design efficient Au-based photocatalysts and spur certain innovations to other metal-based catalysts.

关键词： Au nanostructures Modification strategies Semiconductor Photocatalysis Solar-to-fuel conversion

Collisions, or Reflections and Rotations, Leading to the Digits of π

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Applied Mathematics 2022年第9期13卷 705-732页

作者： franç ois Dubeau Département de Mathématiques Université de Sherbrooke Sherbrooke (QC) Canada

We analyze a problem of elastic collisions between elements of a system composed of two balls and a wall. Thanks to a change of variables, the problem is reduced to a sequence of reflections and rotations. Moreover, the total number of collisions is easily found. for specific ratios of ball weights, the number of collisions is related to the first successive digits of π.

关键词： Dynamical System Elastic Collisions Reflection Rotation Digits of π