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Temporal stability and directional change in a color cline of a marine snail from NW Spain

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Current Zoology 2024年第2期70卷 163-173页

作者： j.an Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez j.an Galindo emilio Rolan-Alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ***,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal *** this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).*** from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated *** compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,except for some directional change and local variability in the frequency of certain *** regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color *** research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

Simulation Architecture for Modelling Interaction Between User and Elbow-articulated Exoskeleton

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j.urnal of Bionic Engineering 2017年第4期14卷 706-715页

作者： Bas j. de Kruif emilio Schmidhauser Konrad S. Stadler Leonard W. O'Sullivan School of Design & Health Research Institute University of Limerick Limerick Ireland Netherlands Organisation for Applied Scientific Research Equipment for Additive Manufacturing 5600 HE Eindhoven The Netherlands Zurich University of Applied Sciences School of Engineering 8401 CH Winterthur Switzerland

The aim of our work is to improve the existing user-exoskeleton models by introducing a simulation architecture that can simulate its dynamic interaction, thereby altering the initial motion of the user. A simulation architecture is developed that uses the musculoskeletal models from OpenSim, and that implements an exoskeleton control algorithm and human response model in Matlab. The musculoskeletal models need to be extended with the response of a user to external forces to simulate the dy- namic interaction. A set of experiments was performed to fit this response model. A validation test showed that more than 80% of the variance of the motion could be explained. With the human response model in the combined simulation architecture, a simulation in which an obj.ct connects with the exoskeleton or with the human is performed. The effect of the exoskeleton on, among others, muscle excitation and altered motion can be assessed with this architecture. Our work can be used to better predict the effect an exoskeleton has on the user.

关键词： human-exoskeleton modelling human response modelling exoskeleton musculoskeletal system exoskeletondesign

Karrikin and Cyanohydrin Smoke Signals Provide Clues to New Endogenous Plant Signaling Compounds

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Molecular Plant 2013年第1期6卷 29-37页

作者： Gavin R. Flematti Mark T. Waters Adrian Scaffidi David j. Merritt emilio L. Ghisalberti' Kingsley W.Dixon Steven M. Smith School of Chemistry and Biochemistry University of Western Australia Crawley 6009 Western Australia Australia Centre in Plant Energy Biology University of Western Australia Crawley 6009 Western Australia Australia School of Plant Biology University of Western Australia Crawley 6009 Western Australia Australia Kings Park and Botanic Garden Fraser Avenue West Perth 6005 Western Australia Australia

Two new types of signaling compounds have been discovered in wildfire smoke due to their ability to stimulate seed germination. The first discovered were karrikins, which share some structural similarity with the strigol- actone class of plant hormones, and both signal through a common F-box protein. However, karrikins and strigolactones operate through otherwise distinct signaling pathways, each distinguished by a specific a/13 hydrolase protein. Genetic analysis suggests that plants contain endogenous compounds that signal specifically through the karrikin pathway. The other active compounds discovered in smoke are cyanohydrins that release germination-stimulating cyanide upon hydrolysis. Cyanohydrins occur widely in plants and have a role in defense against other organisms, but an additional role in endogenous cyanide signaling should also now be considered.

关键词： fire smoke karrikins strigolactones cyanohydrins cyanide seed germination Arabidopsis thaliana.

Self-organized metal-semiconductor epitaxial graphene layer on off-axis 4H-SiC（0001）

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Nano Research 2015年第3期8卷 1026-1037页

作者： Debora Pierucci Haikel Sediri Mahdi Haj.aoui emilio Velez-Fort Yannick j. Dappe Mathieu G. Silly Rachid Belkhou Abhay Shukla Fausto Sirotti Noelle Gogneau Abdelkarim Ouerghi CNRS- Laboratoire de Photonique et de Nanostructures Route de Nozay 91460 Marcoussis France Synchrotron-SOLEIL Saint-Aubin BP48 F91192 Gifsur Yvette Cedex France Universite Pierre et Marie Curie (CNRS - IMPMC) 4 PI. Jussieu 75005 Paris France Service de Physique de rEtat Condense (CNRS URA2464) IRAMIS CEA Saclay 91191 Gif-Sur-Yvette France

The remarkable properties of graphene have shown promise for new perspectives in future electronics, notably for nanometer scale devices. Here we grow graphene epitaxially on an off-axis 4H-SiC（0001） substrate and demonstrate the formation of periodic arrangement of monolayer graphene on planar （0001） terraces and Bernal bilayer graphene on （1120） nanofacets of SiC. We investigate these lateral superlattices using Raman spectroscopy, atomic force microscopy/ electrostatic force microscopy （AFM/EFM） and X-ray and angle resolved photoemission spectroscopy （XPS/ARPES）. The correlation of EFM and ARPES reveals the appearance of permanent electronic band gaps in AB-stacked bilayer graphene on （1120） SiC nanofacets of 150 meV. This feature is confirmed by density functional theory （DFT） calculations. The charge transfer between the substrate and graphene bilayer results in an asymmetric charge distribution between the top and the bottom graphene layers opening an energy gap. This surface organization can be thus defined as self-organized metal-semiconductor graphene.

关键词： epitaxial graphene layer monolayer bilayer band gap opening Bernal stacking off-axis silicon carbide electronic properties

Do non-target species visit feeders and water troughs targeting small game?A study from farmland Spain using camera-trapping

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Integrative Zoology 2021年第2期16卷 226-239页

作者： j.séA.ARMENTEROS j.sús CARO Carlos SÁNCHEZ-GARCÍA Beatriz ARROYO j.séA.PÉREZ Vicente RGAUDIOSO emilio j.TIZADO Department of Animal Production Research Group on Game Species Breeding and ManagementUniversity of LeónLeónSpain Instituto de Investigación en Recursos Cinegéticos(IREC CSIC-UCLM-JCCM)Ciudad RealSpain Fundación Artemisan Ciudad RealSpain Department of Biodiversity and Environmental Management University of LeónPonferradaSpain

Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife,but factors affecting the use of food and water by non-target species are poorly *** evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of *** and water troughs were either“protected”(when surrounded by more than 50%of shrubs/forest)or“open”(in the opposite case).A total of 18948 photos from 5344 camera-trapping days depicted animals,and 75 species were *** and water troughs were visited by target species(partridges and lagomorphs,55.3%of visits)and non-target species(44.7%of visits).Among the latter,corvids were themost common(46.1%of visits),followed by rodents(26.8%),other birds(23.6%,mainly passerines),columbids(1.9%),and other species at minor *** highest proportion of visiting days to feeders and water troughs was from corvids(0.173)followed by otherbirds(0.109)and rodents(0.083);the lowest proportion was recorded for columbids(0.016).Use intensity and visit frequency of water troughs tripled that recorded in feeders,and visits to open feeders/troughs were approximately twice those to protected *** summary:feeders and water troughs targeting small game species are also used regularly by non-target ones;they should be set close to cover to optimize their use by non-target species that are not competitors of target species(though corvids may visit them);water availability should be prioritized where drought periods are expected.

关键词： camera-trapping feeding game species management watering wildlife

ON THE BEST APPROXIMATION MATRIX PROBLEM FOR INTEGRABLE MATRIX FUNCTIONS

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Analysis in Theory and Applications 2000年第3期16卷 56-71页

作者： Defez emilio j.dar Lucas Departmento de Matemática Aplicada Umversidad Politécnica de ValenciaP.O.Box 22.012ValenciaSpain

In this paper positive definite matrix functionals defined on a set of square integrable matrix valued functions are introduced and studied. The best approximation problem is solved in terms of matrix Fourier series. ... 详细信息

关键词： Matrix Function Positive Definite Matrix Matrix Polynomial Matrix Problem Spectral Mapping Theorem

Sex and season explain spleen weight variation in the Egyptian mongoose

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Current Zoology 2019年第1期65卷 11-20页

作者： Victor BANDEIRA emilio Virgos Alexandre AZEVEDO j.ao Carvalho Monica V. CUNHA Carlos Fonseca Dartment of Biology Centro de Estudos do Ambiente e do Mar (CESAM) University of Aveiro Campus Universitario de Santiago Aveiro 3810-193 Portugal Departamento de Biologia Geologia Fisica y Qufmica Inorganica Area Biodiversidad y Conservacion Escuela Superior de Ciencias Experimentales y Tecnologia (ESCET) Universidad Rey Juan Carlos c/Tulipan s/n Mostoles Madrid E-28933 Spain Leibniz Institute for Zoo and Wildlife Research Alfred-Kowalke-Straβe 17 Berlin 10315 Germany Instituto de Ciencias Biomedicas Abel Salazar R. Jorge de Viterbo Ferreira 228 Porto 4050-313 Portugal Instituto Nacional de Investigaqao Agraria e Veterinaria (INIAV) IP-National Institute for Agrarian and Veterinary Research Rua dos Lagidos Lugar da Madalena Vairao 4485-655 Portugal cE3c-Centre for Ecology Evolution and Environmental Changes Faculdade de Ciencias Universidade de Lisboa Lisboa 1749-016 Portugal BiolSI-Biosystems & Integrative Sciences Institute Faculdade de Ciencias Universidade de Lisboa Lisboa 1749-016 Portugal Wildlife Ecology & Health group (WE&H) and Servei d'Ecopatologia de Fauna Salvatge (SEFaS) Departament de Medicina i Cirurgia Animals Universitat Autonoma de Barcelona 08193-Bellaterra Barcelona Spain

The Egyptia n mon goose (Herpestes ichneumon Linn aeus, 1758) is a medium-sized car nivore that experienced remarkable geographic expansion over the last 3 decades in the Iberian Peninsula. In this study, we investigated the association of species-related and abiotic factors with spleen weight (as a proxy for immunocompete nee) in the species. We assessed the relationship of body con dition, sex, age, seas on, and envir onmental conditi ons with splee n weight established for 508 hunted specimens. Our results indicate that the effects of sex and season outweigh those of all other variables, including body condition. Spleen weight is higher in males than in females, and heavier spleens are more likely to be found in spring, coinciding with the highest period of investment in reproduction due to mating, gestation, birth, and lactation. Coupled with the absence of an effect of body condition, our findi ngs suggest that splee n weight variation in this species is mostly influe need by lifehistory traits linked to reproduction, rather than overall energy availability, winter immunoenhancement, or energy partitioning effects, and prompt further research focusing on this topic.

关键词： body condition carnivore Herpestes ichneumon Iberian Peninsula mongoose spleen weight

Quaternary： “Quo Vadis”？

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Episodes 2005年第3期28卷 197-200页

作者： Kenitiro Suguio Alethéea Ernandes Martins Sallun emilio A. A. Soares Centro de Pós-Graduacāo Pesquisa e Extensāo （CEPPE） Universidade Guarulhos （UnG） Praca Tereza Cristina 01-Guarulhos-SP-Brazil-07023-070 Programa de Pós-Graduacāo em Geologia Sedimentar-Instituto de Geociencias Universidade de Sāo Paulo Rua do Lago 562-Sāo Paulo-SP-Brazil-05508-080 Departamento de Geociencias Universidade Federal do Amazonas Av. Gal. Rodrigo O.J. Ramos 3000 Manaus-AM-Brazil-69077-000

The Quaternary, like the long-abandoned terms Primary, Secondary and Tertiary, is a very ambiguous word, whose chronological meaning is not very well defined. Its usage spread very quickly, perhaps due to its more-or-less close relationship with the human history and with the latest glaciations. However, the oldest of human fossil record, according to recent discoveries in Africa （Dj.urab Desert in Tchad）, is about 7 million years old, rather than 2 million years as suggested by fossils at OlduvaL Moreover, for some time now, it has been known that the first Quaternary-type glaciations occurred in several regions of the Earth between 2.5 and 3 million years ago, that is prior to the Pliocene-Pleistocene limit at 1.81 million years ago, as determined by the GSSP. These facts have led some researchers, mostly from the International Union of Geological Sciences （lUGS）, and from the International Association for Quaternary Research （INQUA）, to suggest changes in the subdivision of the Neocenozoic. Certainly, discussions on this subj.ct will be raised at many scientific meetings in the near future until almost unanimous agreement can be attained. Some additional suggestions are presented here, as a contribution to resolution of these nomenclatorial issues.

关键词：冰河作用化石非洲更新世上新世冰川