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Author Alméras, T.; Gronvold, A.; van der Lee, A.; Clair, B.; Montero, C. url  doi
openurl 
  Title Contribution of cellulose to the moisture-dependent elastic behaviour of wood Type Journal Article
  Year 2017 Publication Composites Science and Technology Abbreviated Journal Composites Science and Technology  
  Volume 138 Issue Pages 151-160  
  Keywords Cellulose; Crystal strain; Micromechanics; Wood; X-ray diffraction  
  Abstract Wood has a hierarchical structure involving several levels of organisation. The stiffness of wood relies on its capacity to transfer mechanical stress to its stiffest element at the lowest scale, namely crystalline cellulose. This study aims at quantifying to what extend crystalline cellulose contributes to wood stiffness depending on its moisture content. The crystal strains of cellulose were measured using X-ray diffraction on wet and dry specimens of spruce, based on a previously published methodology. The comparison between crystal strain and macroscopic strain shows that, during elastic loading, cellulose strain is lower than macroscopic strain. The means ratio of crystal/macroscopic strain amounts 0.85 for dry specimens and 0.64 for wet specimens. This strain ratio cannot be explained just by the projection effect due to the difference in orientation between cellulose microfibrils and cell wall, but results from deformation mechanisms in series with cellulose. Analysis shows that this series contribution represents a non-negligible contribution to wood compliance and is strongly moisture-dependent. This contribution amounts 9% for dry specimens and 33% for wet specimens, corresponding to a 4-fold increase in compliance for the series contribution. The origin of these strains is ascribed to mechanisms involving bending or shear strain at different scales, due to the fact that reinforcing element are neither perfectly straight nor infinitely long. © 2016  
  Address (down) CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), AgroParisTech, Cirad, INRA, Université des Antilles, Université de Guyane, Kourou, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes Export Date: 26 December 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 701  
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Author Vantaux, A.; Roux, O.; Magro, A.; Orivel, J. url  openurl
  Title Evolutionary perspectives on myrmecophily in ladybirds Type Journal Article
  Year 2012 Publication Psyche Abbreviated Journal Psyche  
  Volume 591570 Issue Pages 1-7  
  Keywords  
  Abstract Myrmecophiles are species that usually have developed specialized traits to cope with the aggressiveness of ants enabling them to live in their vicinity. Many coccinellid species are predators of Hemiptera; the latter is also often protected by ants. Therefore these ladybirds frequently interact with ants, and some species have become myrmecophilous. In this paper, we aim to provide an overview of the evolution of myrmecophilous traits in ladybirds. We then discuss the costs and benefits of myrmecophily and the dietary shift to myrmecophagy observed in a few species. Copyright © 2012 Amélie Vantaux et al.  
  Address (down) CNRS, UMR EcoFoG-Ecologie des Forêts de Guyane, Campus Agronomique, BP 316, 97379 Kourou Cedex, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00332615 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 28 March 2012; Source: Scopus; Art. No.: 591570; doi: 10.1155/2012/591570; Language of Original Document: English; Correspondence Address: Vantaux, A.; Entomology Laboratory, Zoological Institute, Catholic University of Leuven, Naamsestraat 59, 3000 Leuven, Belgium; email: amelie.vantaux@gmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 388  
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Author Cachet, N.; Ho-A-Kwie, F.; Rivaud, M.; Houel, E.; Deharo, E.; Bourdy, G.; Jullian, V. url  openurl
  Title Picrasin K, a new quassinoid from Quassia amara L. (Simaroubaceae) Type Journal Article
  Year 2012 Publication Phytochemistry Letters Abbreviated Journal Phytochem. Lett.  
  Volume 5 Issue 1 Pages 162-164  
  Keywords Malaria; P. falciparum; Quassia amara; Quassinoids; Simaroubaceae  
  Abstract A new quassinoid Picrasin K 1 was isolated from a decoction made of Quassia amara leaves, traditionally used in French Guyana to treat malaria. The structure and relative stereochemistry of 1 was determined through extensive NMR analysis. Picrasin K showed a low activity against Plasmodium falciparum in vitro (IC 50 = 8 μM), and a similar low activity on human cancerous cells line (IC 50 = 7 μM on MCF-7 cells line). © 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.  
  Address (down) CNRS, UMR Ecofog, Université des Antilles et de la Guyane, Cayenne, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 18743900 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 8 March 2012; Source: Scopus; doi: 10.1016/j.phytol.2011.12.001; Language of Original Document: English; Correspondence Address: Jullian, V.; UMR-152 Pharma-Dev, IRD, Université Paul Sabatier Toulouse 3, 31062 Toulouse, France; email: jullian@cict.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 382  
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Author Rahali, H.; Stien, D. openurl 
  Title Highly-loaded amphiphilic polyimino resin: quench reagent and solid support for peptide synthesis Type Journal Article
  Year 2006 Publication Tetrahedron Letters Abbreviated Journal Tetrahedron Lett.  
  Volume 47 Issue 47 Pages 8205-8207  
  Keywords  
  Abstract We demonstrate herein that polyimino resin 4a prepared by condensation of alpha,alpha'-dichloro-p-xylene, ethylenediamine and tris-(2-aminoethyl)-amine can be successfully exploited as a quench reagent for acids and electrophiles both in aqueous and organic solutions. Scope and limitations of such a resin as a solid support for peptide synthesis were also investigated. (c) 2006 Elsevier Ltd. All rights reserved.  
  Address (down) CNRS, UMR Ecofog, Inst Enseignement Super Guyane, F-97337 Cayenne, France, Email: didier.stien@guyane.cnrs.fr  
  Corporate Author Thesis  
  Publisher PERGAMON-ELSEVIER SCIENCE LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0040-4039 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000241910200002 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 172  
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Author Piponiot, C.; Cabon, A.; Descroix, L.; Dourdain, A.; Mazzei, L.; Ouliac, B.; Rutishauser, E.; Sist, P.; Herault, B. pdf  url
doi  openurl
  Title A methodological framework to assess the carbon balance of tropical managed forests Type Journal Article
  Year 2016 Publication Carbon Balance and Management Abbreviated Journal Carbon Balance and Management  
  Volume 11 Issue 1 Pages  
  Keywords Amazonia; Carbon cycle; Error propagation; Production forests; Selective logging  
  Abstract Background: Managed forests are a major component of tropical landscapes. Production forests as designated by national forest services cover up to 400 million ha, i.e. half of the forested area in the humid tropics. Forest management thus plays a major role in the global carbon budget, but with a lack of unified method to estimate carbon fluxes from tropical managed forests. In this study we propose a new time- and spatially-explicit methodology to estimate the above-ground carbon budget of selective logging at regional scale. Results: The yearly balance of a logging unit, i.e. the elementary management unit of a forest estate, is modelled by aggregating three sub-models encompassing (i) emissions from extracted wood, (ii) emissions from logging damage and deforested areas and (iii) carbon storage from post-logging recovery. Models are parametrised and uncertainties are propagated through a MCMC algorithm. As a case study, we used 38 years of National Forest Inventories in French Guiana, northeastern Amazonia, to estimate the above-ground carbon balance (i.e. the net carbon exchange with the atmosphere) of selectively logged forests. Over this period, the net carbon balance of selective logging in the French Guianan Permanent Forest Estate is estimated to be comprised between 0.12 and 1.33 Tg C, with a median value of 0.64 Tg C. Uncertainties over the model could be diminished by improving the accuracy of both logging damage and large woody necromass decay submodels. Conclusions: We propose an innovating carbon accounting framework relying upon basic logging statistics. This flexible tool allows carbon budget of tropical managed forests to be estimated in a wide range of tropical regions. © 2016 The Author(s).  
  Address (down) CNRS, UMR EcoFoG, AgroParisTech, Inra, Université de la Guyane, Université des Antilles, Cirad, Campus Agronomique, Kourou, French Guiana  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  Area Expedition Conference  
  Notes Export Date: 1 September 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 688  
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Author Dejean, A.; Petitclerc, F.; Azémar, F. doi  openurl
  Title Seasonality influences ant-mediated nutrient acquisition (myrmecotrophy) by a Neotropical myrmecophyte Type Journal Article
  Year 2020 Publication Evolutionary Ecology Abbreviated Journal Evol. Ecol.  
  Volume 34 Issue 4 Pages 645-657  
  Keywords Ant-plant relationships; Mutualism; Myrmecophyte; Myrmecotrophy; Phenology; Stable isotopes; ant; herb; host plant; life cycle; myrmecochory; myrmecophyte; Neotropical Region; phenology; seasonality; stable isotope; understory; Gentianaceae; Tachia; Tachia guianensis  
  Abstract Tachia guianensis (Gentianaceae), a Neotropical understory myrmecophyte, shelters ant colonies in its hollow trunks and branches (domatia). In turn, it is protected from defoliators and obtains nutrients from ant-produced wastes (myrmecotrophy). Aiming to verify if seasonality influences nitrogen assimilation via ant wastes using the stable isotope nitrogen-15, we first studied Tachia’s phenology and its seasonal leaf production, and then the life cycle of its two more frequent guest ant species. We found that leaf production was much higher during the rainy than the dry season. Mature guest ant colonies produced sexuals regardless of the season and the net weight of the waste piles inside the domatia did not vary between seasons, so that the availability of nutrients to their host plant is steady year-long. By providing the two most frequent mutualistic guest ant species with food enriched with nitrogen-15, we showed that Tachia individuals assimilate more nitrogen from ant wastes during the rainy season, when the plant is physiologically active, compared to the dry season. Thus, one can deduce that the increase in nitrogen assimilation during the rainy season is determined by the increase in Tachia’s physiological activity during that season. Information gathered through a bibliographic compilation confirms that none of the 15 ant species known to be associated with myrmecophytes for which the life cycle was studied is characterized by seasonal reproduction (which would result in fluctuating waste production). The same is true for 49.7% of 167 tropical ant species (seasonal production for the remaining species). We concluded that, in contrast to the non-seasonal ant colony reproductive cycle, Tachia’s phenology determines the myrmecotrophic assimilation rate. © 2020, Springer Nature Switzerland AG.  
  Address (down) CNRS, UMR EcoFoG, AgroParisTech, CIRAD, INRAE, Université des Antilles, Université de Guyane, Kourou, 97310, France  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 02697653 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 956  
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Author Ghislain, B.; Clair, B. pdf  url
doi  openurl
  Title Diversity in the organisation and lignification of tension wood fibre walls – A review Type Journal Article
  Year 2017 Publication IAWA Journal Abbreviated Journal  
  Volume 38 Issue 2 Pages 245-265  
  Keywords diversity; fibres; G-layer; lignification; multilayered tension wood fibre walls; S1 + S2 + S3 + G; Tension wood  
  Abstract Tension wood, a tissue developed by angiosperm trees to actively recover their verticality, has long been defined by the presence of an unlignified cellulosic inner layer in the cell wall of fibres, called the G-layer. Although it was known that some species have no G-layer, the definition was appropriate since it enabled easy detection of tension wood zones using various staining techniques for either cellulose or lignin. For several years now, irrespective of its anatomical structure, tension wood has been defined by its high mechanical internal tensile stress. This definition enables screening of the diversity of cell walls in tension wood fibres. Recent results obtained in tropical species with tension wood with a delay in the lignification of the G-layer opened our eyes to the effective presence of large amounts of lignin in the G-layer of some species. This led us to review older literature mentioning the presence of lignin deposits in the G-layer and give them credit. Advances in the knowledge of tension wood fibres allow us to reconsider some previous classifications of the diversity in the organisation of the fibre walls of the tension wood. © 2017 International Association of Wood Anatomists.  
  Address (down) CNRS, UMR EcoFoG, AgroParisTech, Cirad, INRA, Université des Antilles, Université de Guyane, Kourou, France  
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  Notes Export Date: 2 September 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 763  
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Author Barassé, V.; Touchard, A.; Téné, N.; Tindo, M.; Kenne, M.; Klopp, C.; Dejean, A.; Bonnafé, E.; Treilhou, M. pdf  url
doi  openurl
  Title The peptide venom composition of the fierce stinging ant tetraponera aethiops (formicidae: Pseudomyrmecinae) Type Journal Article
  Year 2019 Publication Toxins Abbreviated Journal Toxins  
  Volume 11 Issue 12 Pages 732  
  Keywords Defensive venom; Dimeric peptides; Peptidome; Tetraponera aethiops  
  Abstract In the mutualisms involving certain pseudomyrmicine ants and different myrmecophytes (i.e., plants sheltering colonies of specialized “plant-ant” species in hollow structures), the ant venom contributes to the host plant biotic defenses by inducing the rapid paralysis of defoliating insects and causing intense pain to browsing mammals. Using integrated transcriptomic and proteomic approaches, we identified the venom peptidome of the plant-ant Tetraponera aethiops (Pseudomyrmecinae). The transcriptomic analysis of its venom glands revealed that 40% of the expressed contigs encoded only seven peptide precursors related to the ant venom peptides from the A-superfamily. Among the 12 peptide masses detected by liquid chromatography-mass spectrometry (LC-MS), nine mature peptide sequences were characterized and confirmed through proteomic analysis. These venom peptides, called pseudomyrmecitoxins (PSDTX), share amino acid sequence identities with myrmeciitoxins known for their dual offensive and defensive functions on both insects and mammals. Furthermore, we demonstrated through reduction/alkylation of the crude venom that four PSDTXs were homo- and heterodimeric. Thus, we provide the first insights into the defensive venom composition of the ant genus Tetraponera indicative of a streamlined peptidome.  
  Address (down) CNRS, UMR EcoFoG, AgroParisTech, Cirad, INRA, Université des Antilles, Université de Guyane, Kourou, 97310, France  
  Corporate Author Thesis  
  Publisher Mdpi Ag Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20726651 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 902  
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Author Rodrigues, A.M.S.; Eparvier, V.; Odonne, G.; Amusant, N.; Stien, D.; Houël, E. pdf  url
doi  openurl
  Title The antifungal potential of (Z)-ligustilide and the protective effect of eugenol demonstrated by a chemometric approach Type Journal Article
  Year 2019 Publication Scientific Reports Abbreviated Journal Sci. Rep.  
  Volume 9 Issue Pages 8729  
  Keywords  
  Abstract Mankind is on the verge of a postantibiotic era. New concepts are needed in our battle to attenuate infectious diseases around the world and broad spectrum plant-inspired synergistic pharmaceutical preparations should find their place in the global fight against pathogenic microorganisms. To progress towards the discovery of potent antifungal agents against human pathologies, we embarked upon developing chemometric approach coupled with statistical design to unravel the origin of the anticandidal potential of a set of 66 essential oils (EOs). EOs were analyzed by GC-MS and tested against Candida albicans and C. parapsilosis (Minimal Inhibitory Concentration, MIC). An Orthogonal Partial Least Square (OPLS) analysis allowed us to identify six molecules presumably responsible for the anticandidal activity of the oils: (Z)-ligustilide, eugenol, eugenyl acetate, citral, thymol, and β-citronellol. These compounds were combined following a full factorial experimental design approach in order to optimize the anticandidal activity and selectivity index (SI = IC50(MRC5 cells)/MIC) through reconstituted mixtures. (Z)-Ligustilide and citral were the most active compounds, while (Z)-ligustilide and eugenol were the two main factors that most contributed to the increase of the SI. These two terpenes can, therefore, be used to construct bioinspired synergistic anticandidal mixtures. © 2019, The Author(s).  
  Address (down) CNRS, UMR EcoFoG, AgroParisTech, Cirad, INRA, Université des Antilles, Université de Guyane, Cayenne, 97300, France  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20452322 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 876  
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Author Shepard, W.D.; Clavier, S.; Cerdan, A. doi  openurl
  Title A generic key to the known larval elmidae (Insecta: Coleoptera) of French Guiana Type Journal Article
  Year 2020 Publication Papeis Avulsos de Zoologia Abbreviated Journal Pap. Avulsos Zool.  
  Volume 60 Issue Special Pages e202060  
  Keywords Biodiversity; Identification; Immatures; Neotropical; Survey  
  Abstract An identification key is provided for 21 larval types of Elmidae (riffle beetles) known to occur in French Guiana. Not all elmid genera known to occur in French Guiana are known in the larval stage. Nor are all the known larval types assigned to known elmid genera. © 2020, Universidade de Sao Paulo. All rights reserved.  
  Address (down) CNRS, UMR EcoFog (AgroParisTech, CIRAD, INRA, Université des Antilles, Université de Guyane), Kourou Cedex, France  
  Corporate Author Thesis  
  Publisher Universidade de Sao Paulo Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00311049 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 980  
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