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Author Heuertz, M.; Caron, H.; Scotti-Saintagne, C.; Pétronelli, P.; Engel, J.; Tysklind, N.; Miloudi, S.; Gaiotto, F.A.; Chave, J.; Molino, J.-F.; Sabatier, D.; Loureiro, J.; Budde, K.B. pdf  doi
openurl 
  Title The hyperdominant tropical tree Eschweilera coriacea (Lecythidaceae) shows higher genetic heterogeneity than sympatric Eschweilera species in French Guiana Type Journal Article
  Year 2020 Publication Plant Ecology and Evolution Abbreviated Journal Plant Ecol. Evol.  
  Volume 153 Issue 1 Pages 67-81  
  Keywords Cryptic species; Eschweilera; Hyperdominant tropical trees; Microsatellites; Species complex; Species delimitation  
  Abstract Background and aims – The evolutionary history of Amazonia’s hyperabundant tropical tree species, also known as “hyperdominant” species, remains poorly investigated. We assessed whether the hyperdominant Eschweilera coriacea (DC.) S.A.Mori (Lecythidaceae) represents a single genetically cohesive species, and how its genetic constitution relates to other species from the same clade with which it occurs sympatrically in French Guiana. Methods – We sampled 152 individuals in nine forest sites in French Guiana, representing 11 species of the genus Eschweilera all belonging to the Parvifolia clade, with emphasis on E. coriacea. Samples were genotyped at four simple sequence repeat (SSR) markers. We delimited gene pools, i.e., genetically coherent putative taxa, using STRUCTURE software and principal component analysis. We compared the genetic assignment of individuals with their morphological species determination and estimated genetic diversity and differentiation for gene pools and species. We also estimated genome size using flow cytometry. Key results – SSR profiles commonly displayed up to four alleles per genotype, suggesting that the investigated Eschweilera species bear a paleopolyploid signature. Flow cytometry suggested that the studied species are diploid with haploid genome sizes of 871–1046 Mbp. We detected five gene pools and observed a good correspondence between morphological and genetic delimitation for Eschweilera sagotiana Miers and the undescribed morphospecies E. sp. 3 (which resembles E. grandiflora (Aubl.) Sandwith), and to a lesser extent for E. decolorans Sandwith and E. micrantha (O.Berg) Miers. Eschweilera coriacea was the most genetically diverse species and included individuals assigned to each gene pool. Conclusions – We found no conclusive evidence for cryptic species within E. coriacea in French Guiana. SSRs detected fewer gene pools than expected based on morphology in the Parvifolia clade but discriminated evolutionary relationships better than available plastid markers. A positive trend between demographic abundance of species and allelic richness illustrates that hyperdominants may have a high evolutionary potential. This hypothesis can be tested using more powerful genomic data in combination with tree phenotypic trait variation and characterization of niche breadth, to enhance our understanding of the causes of hyperdominance in Amazonian trees.  
  Address (up) University of Copenhagen, Forest, Nature and Biomass, Rolighedsvej 23, Frederiksberg C, DK-1958, Denmark  
  Corporate Author Thesis  
  Publisher Societe Royale de Botanique de Belgique Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20323913 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 928  
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Author Phillips, O.L.; Brienen, R.J.W.; Gloor, E.; Baker, T.R.; Lloyd, J.; Lopez-Gonzalez, G.; Monteagudo-Mendoza, A.; Malhi, Y.; Lewis, S.L.; Vásquez Martinez, R.; Alexiades, M.; Álvarez Dávila, E.; Alvarez-Loayza, P.; Andrade, A.; Aragão, L.E.O.C.; Araujo-Murakami, A.; Arets, E.J.M.M.; Arroyo, L.; Aymard, G.A.; Bánki, O.S.; Baraloto, C.; Barroso, J.; Bonal, D.; Boot, R.G.A.; Camargo, J.L.C.; Castilho, C.V.; Chama, V.; Chao, K.J.; Chave, J.; Comiskey, J.A.; Valverde, F.C.; da Costa, L.; de Oliveira, E.A.; Di Fiore, A.; Erwin, T.L.; Fauset, S.; Forsthofer, M.; Galbraith, D.R.; Grahame, E.S.; Groot, N.; Herault, B.; Higuchi, N.; Honorio Coronado, E.N.; Keeling, H.; Killeen, T.J.; Laurance, W.F.; Laurance, S.; Licona, J.; Magnusson, W.E.; Marimon, B.S.; Marimon-Junior, B.H.; Mendoza, C.; Neill, D.A.; Nogueira, E.M.; Núñez, P.; Pallqui Camacho, N.C.; Parada, A.; Pardo-Molina, G.; Peacock, J.; Peña-Claros, M.; Pickavance, G.C.; Pitman, N.C.A.; Poorter, L.; Prieto, A.; Quesada, C.A.; Ramírez, F.; Ramírez-Angulo, H.; Restrepo, Z.; Roopsind, A.; Rudas, A.; Salomão, R.P.; Schwarz, M.; Silva, N.; Silva-Espejo, J.E.; Silveira, M.; Stropp, J.; Talbot, J.; ter Steege, H.; Teran-Aguilar, J.; Terborgh, J.; Thomas-Caesar, R.; Toledo, M.; Torello-Raventos, M.; Umetsu, R.; van der Heijden, G.M.F.; van der Hout, P.; Guimarães Vieira, I.C.; Vieira, S.A.; Vilanova, E.; Vos, V.A.; Zagt, R.J.; Alarcon, A.; Amaral, I.; Camargo, P.B.; Brown, I.F.; Blanc, L.; Burban, B.; Cardozo, N.; Engel, J.; de Freitas, M.A.; de Oliveira, A.; Fredericksen, T.S.; Ferreira, L.; Hinojosa, N.T.; Jimenez, E.; Lenza, E.; Mendoza, C.; Mendoza Polo, I.; Peña Cruz, A.; Peñuela, M.C.; Petronelli, P.; Singh, J.; Maquirino, P.; Serano, J.; Sota, A.; Oliveira dos Santos, C.; Ybarnegaray, J.; Ricardo, J. pdf  url
doi  openurl
  Title Carbon uptake by mature Amazon forests has mitigated Amazon nations' carbon emissions Type Journal Article
  Year 2017 Publication Carbon Balance and Management Abbreviated Journal Carbon Balance and Management  
  Volume 12 Issue 1 Pages  
  Keywords Amazonia; Carbon balance; Carbon sink; Climate change; Ecosystem service; Land use change; Sequestration; Tropical forests  
  Abstract Background: Several independent lines of evidence suggest that Amazon forests have provided a significant carbon sink service, and also that the Amazon carbon sink in intact, mature forests may now be threatened as a result of different processes. There has however been no work done to quantify non-land-use-change forest carbon fluxes on a national basis within Amazonia, or to place these national fluxes and their possible changes in the context of the major anthropogenic carbon fluxes in the region. Here we present a first attempt to interpret results from ground-based monitoring of mature forest carbon fluxes in a biogeographically, politically, and temporally differentiated way. Specifically, using results from a large long-term network of forest plots, we estimate the Amazon biomass carbon balance over the last three decades for the different regions and nine nations of Amazonia, and evaluate the magnitude and trajectory of these differentiated balances in relation to major national anthropogenic carbon emissions. Results: The sink of carbon into mature forests has been remarkably geographically ubiquitous across Amazonia, being substantial and persistent in each of the five biogeographic regions within Amazonia. Between 1980 and 2010, it has more than mitigated the fossil fuel emissions of every single national economy, except that of Venezuela. For most nations (Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname) the sink has probably additionally mitigated all anthropogenic carbon emissions due to Amazon deforestation and other land use change. While the sink has weakened in some regions since 2000, our analysis suggests that Amazon nations which are able to conserve large areas of natural and semi-natural landscape still contribute globally-significant carbon sequestration. Conclusions: Mature forests across all of Amazonia have contributed significantly to mitigating climate change for decades. Yet Amazon nations have not directly benefited from providing this global scale ecosystem service. We suggest that better monitoring and reporting of the carbon fluxes within mature forests, and understanding the drivers of changes in their balance, must become national, as well as international, priorities. © 2017 The Author(s).  
  Address (up) University of Leeds, School of Geography, Leeds, United Kingdom  
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  Notes Export Date: 20 February 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 735  
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Author Talaga, S.; Dejean, A.; Azémar, F.; Dumont, Y.; Leroy, C. doi  openurl
  Title Impacts of biotic and abiotic parameters on immature populations of Aedes aegypti Type Journal Article
  Year 2020 Publication Journal of Pest Science Abbreviated Journal J. Pest Sci.  
  Volume 93 Issue 3 Pages 941-952  
  Keywords Biocontrol agents; Competition; Ecosystem services; Mosquito control; Mosquito management; Predation; abiotic factor; biotic factor; competitive displacement; disease vector; maturation; mosquito; pest control; Aedes aegypti; Hexapoda; Zika virus  
  Abstract In recent centuries, the mosquito Aedes aegypti has spread into most urban areas throughout the tropics. This species is considered the main vector of the chikungunya, dengue, yellow fever and Zika viruses and causes major public health issues. The aim of this study is to investigate the relative influence of biotic and abiotic parameters on immature populations of Ae. aegypti. During a one-year-long field experiment, we monitored 108 macroinvertebrate aquatic communities inhabiting four types of water containers across three different urbanized sites in a Neotropical city. A multimodel inference approach revealed that, in addition to abiotic parameters, biotic interactions with aquatic organisms had an important influence on the abundance of Ae. aegypti and that the urbanized site considered influences the outcomes of the interactions. Controphic species other than mosquitoes aided Ae. aegypti development, suggesting a mechanism of facilitation through a chain of processes. However, the abundance of Ae. aegypti was lowered by competition with native mosquito species in the slightly urbanized area and by predation in more urbanized areas. Competitive displacement and reduction, as well as predation by native aquatic organisms, can be considered a form of ecosystem service. The conservation and/or augmentation of natural enemies should improve the short- and long-term success of incompatible and/or sterile insect techniques, thus opening up perspectives for the future of mosquito management. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.  
  Address (up) University of Pretoria, Department of Mathematics and Applied Mathematics, Pretoria, South Africa  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 16124758 (Issn) ISBN Medium  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 962  
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Author Touchard, A.; Aili, S.R.; Téné, N.; Barassé, V.; Klopp, C.; Dejean, A.; Kini, R.M.; Mrinalini; Coquet, L.; Jouenne, T.; Lefranc, B.; Leprince, J.; Escoubas, P.; Nicholson, G.M.; Treilhou, M.; Bonnafé, E. url  doi
openurl 
  Title Venom Peptide Repertoire of the European Myrmicine Ant Manica rubida: Identification of Insecticidal Toxins Type Journal Article
  Year 2020 Publication Journal of proteome research Abbreviated Journal J. Proteome Res.  
  Volume 19 Issue 4 Pages 1800-1811  
  Keywords glycosylated toxin; peptidome; polycationic α-helix; predation; pyroglutamate; reversible neurotoxicity  
  Abstract Using an integrated transcriptomic and proteomic approach, we characterized the venom peptidome of the European red ant, Manica rubida. We identified 13 “myrmicitoxins” that share sequence similarities with previously identified ant venom peptides, one of them being identified as an EGF-like toxin likely resulting from a threonine residue modified by O-fucosylation. Furthermore, we conducted insecticidal assays of reversed-phase HPLC venom fractions on the blowfly Lucilia caesar, permitting us to identify six myrmicitoxins (i.e., U3-, U10-, U13-, U20-MYRTX-Mri1a, U10-MYRTX-Mri1b, and U10-MYRTX-Mri1c) with an insecticidal activity. Chemically synthesized U10-MYRTX-Mri1a, -Mri1b, -Mri1c, and U20-MYRTX-Mri1a irreversibly paralyzed blowflies at the highest doses tested (30-125 nmol·g-1). U13-MYRTX-Mri1a, the most potent neurotoxic peptide at 1 h, had reversible effects after 24 h (150 nmol·g-1). Finally, U3-MYRTX-Mri1a has no insecticidal activity, even at up to 55 nmol·g-1. Thus, M. rubida employs a paralytic venom rich in linear insecticidal peptides, which likely act by disrupting cell membranes.  
  Address (up) VenomeTech, 473 Route des Dolines – Villa 3, Valbonne, 06560, France  
  Corporate Author Thesis  
  Publisher NLM (Medline) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 15353907 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 20 April 2020 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 927  
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Author Touchard, A.; Brust, A.; Cardoso, F.C.; Chin, Y.K.-Y.; Herzig, V.; Jin, A.-H.; Dejean, A.; Alewood, P.F.; King, G.F.; Orivel, J.; Escoubas, P. url  doi
openurl 
  Title Isolation and characterization of a structurally unique β-hairpin venom peptide from the predatory ant Anochetus emarginatus Type Journal Article
  Year 2016 Publication Biochimica et Biophysica Acta – General Subjects Abbreviated Journal Biochimica et Biophysica Acta – General Subjects  
  Volume 1860 Issue 11 Pages 2553-2562  
  Keywords Anochetus; Ant venom; Disulfide-rich peptides; L-type calcium channels; Neurotoxin; Poneritoxins; U1-PONTX-Ae1a  
  Abstract Background Most ant venoms consist predominantly of small linear peptides, although some contain disulfide-linked peptides as minor components. However, in striking contrast to other ant species, some Anochetus venoms are composed primarily of disulfide-rich peptides. In this study, we investigated the venom of the ant Anochetus emarginatus with the aim of exploring these novel disulfide-rich peptides. Methods The venom peptidome was initially investigated using a combination of reversed-phase HPLC and mass spectrometry, then the amino acid sequences of the major peptides were determined using a combination of Edman degradation and de novo MS/MS sequencing. We focused on one of these peptides, U1-PONTX-Ae1a (Ae1a), because of its novel sequence, which we predicted would form a novel 3D fold. Ae1a was chemically synthesized using Fmoc chemistry and its 3D structure was elucidated using NMR spectroscopy. The peptide was then tested for insecticidal activity and its effect on a range of human ion channels. Results Seven peptides named poneritoxins (PONTXs) were isolated and sequenced. The three-dimensional structure of synthetic Ae1a revealed a novel, compact scaffold in which a C-terminal β-hairpin is connected to the N-terminal region via two disulfide bonds. Synthetic Ae1a reversibly paralyzed blowflies and inhibited human L-type voltage-gated calcium channels (CaV1). Conclusions Poneritoxins from Anochetus emarginatus venom are a novel class of toxins that are structurally unique among animal venoms. General significance This study demonstrates that Anochetus ant venoms are a rich source of novel ion channel modulating peptides, some of which might be useful leads for the development of biopesticides. © 2016  
  Address (up) VenomeTech, 473 Route des Dolines, Valbonne, France  
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  Notes Export Date: 15 September 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 694  
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Author Aili, S.R.; Touchard, A.; Koh, J.M.S.; Dejean, A.; Orivel, J.; Padula, M.P.; Escoubas, P.; Nicholson, G.M. url  doi
openurl 
  Title Comparisons of Protein and Peptide Complexity in Poneroid and Formicoid Ant Venoms Type Journal Article
  Year 2016 Publication Journal of Proteome Research Abbreviated Journal Journal of Proteome Research  
  Volume 15 Issue 9 Pages 3039-3054  
  Keywords ant venom; Hymenoptera; Lc-Maldi-Tof Ms; mass spectrometry; nanoLC-ESI-QTOF MS/MS; peptidome; proteomic analysis; toxin  
  Abstract Animal venom peptides are currently being developed as novel drugs and bioinsecticides. Because ants use venoms for defense and predation, venomous ants represent an untapped source of potential bioactive toxins. This study compared the protein and peptide components of the poneroid ants Neoponera commutata, Neoponera apicalis, and Odontomachus hastatus and the formicoid ants Ectatomma tuberculatum, Ectatomma brunneum, and Myrmecia gulosa. 1D and 2D PAGE revealed venom proteins in the mass range <10 to >250 kDa. NanoLC-ESI-QTOF MS/MS analysis of tryptic peptides revealed the presence of common venom proteins and also many undescribed proteins. RP-HPLC separation followed by MALDI-TOF MS of the venom peptides also revealed considerable heterogeneity. It was found that the venoms contained between 144 and 1032 peptides with 5-95% of peptides in the ranges 1-4 and 1-8 kDa for poneroid and formicoid ants, respectively. By employing the reducing MALDI matrix 1,5-diaminonapthalene, up to 28 disulfide-bonded peptides were also identified in each of the venoms. In particular, the mass range of peptides from poneroid ants is lower than peptides from other venoms, indicating possible novel structures and pharmacologies. These results indicate that ant venoms represent an enormous, untapped source of novel therapeutic and bioinsecticide leads. © 2016 American Chemical Society.  
  Address (up) VenomeTech, 473 Route des Dolines, Valbonne, 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  
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  Area Expedition Conference  
  Notes Export Date: 15 September 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 695  
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Author Touchard, A.; Koh, J.M.S.; Aili, S.R.; Dejean, A.; Nicholson, G.M.; Orivel, J.; Escoubas, P. url  openurl
  Title The complexity and structural diversity of ant venom peptidomes is revealed by mass spectrometry profiling Type Journal Article
  Year 2015 Publication Rapid Communications in Mass Spectrometry Abbreviated Journal Rapid Communications in Mass Spectrometry  
  Volume 29 Issue 5 Pages 385-396  
  Keywords  
  Abstract Rationale Compared with other animal venoms, ant venoms remain little explored. Ants have evolved complex venoms to rapidly immobilize arthropod prey and to protect their colonies from predators and pathogens. Many ants have retained peptide-rich venoms that are similar to those of other arthropod groups. Methods With the goal of conducting a broad and comprehensive survey of ant venom peptide diversity, we investigated the peptide composition of venoms from 82 stinging ant species from nine subfamilies using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). We also conducted an in-depth investigation of eight venoms using reversed-phase high-performance liquid chromatography (RP-HPLC) separation coupled with offline MALDI-TOFMS. Results Our results reveal that the peptide compositions of ant venom peptidomes from both poneroid and formicoid ant clades comprise hundreds of small peptides (<4 kDa), while large peptides (>4 kDa) are also present in the venom of formicoids. Chemical reduction revealed the presence of disulfide-linked peptides in most ant subfamilies, including peptides structured by one, two or three disulfide bonds as well as dimeric peptides reticulated by three disulfide bonds. Conclusions The biochemical complexity of ant venoms, associated with an enormous ecological and taxonomic diversity, suggests that stinging ant venoms constitute a promising source of bioactive molecules that could be exploited in the search for novel drug and biopesticide leads. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.  
  Address (up) VenomeTech, 473 Route des DolinesValbonne, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
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  Series Editor Series Title Abbreviated Series Title  
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  Notes Export Date: 24 April 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 599  
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Author Siebicke, L.; Hunner, M.; Foken, T. url  openurl
  Title Aspects of CO 2 advection measurements Type Journal Article
  Year 2012 Publication Theoretical and Applied Climatology Abbreviated Journal Theor. Appl. Climatol.  
  Volume 109 Issue 1-2 Pages 109-131  
  Keywords  
  Abstract Observations of vegetation-atmosphere exchange of carbon dioxide (CO 2) by the eddy covariance (EC) technique are limited by difficult conditions such as nighttime and heterogeneous terrain. Thus, advective flux components are included into the net ecosystem exchange (NEE) budget. However, advection measurements are experimentally challenging and do not always help to solve the night flux problem of the EC technique. This study investigates alternative methods for the observation of horizontal advection, in particular horizontal concentration gradients, as well as different approaches to coordinate rotation and vertical advection. Continuous high-frequency measurements of the horizontal CO 2 concentration field are employed and compared to the often used discontinuous sequential sampling. Significant differences were found in the case of 30-min mean concentration values between the conventional discontinuous sampling approach and the complete observation of the time series by continuous sampling. Estimates of vertical advection rely on accurate estimates of vertical wind velocity (W). Therefore, different approaches to the planar fit coordinate rotation have been investigated. Sector-wise rotation was able to eliminate directional dependencies of mean W. Furthermore, the effect of the data set length used for rotation (window length) was investigated and was found to have significant impact on estimates of vertical advection, with larger window lengths yielding about 50% larger vertical advection. A sequential planar fit with controlled window length is proposed to give reproducible results. The different approaches to the measurement and calculation of horizontal and vertical advection presented are applied to data obtained during the exchange processes in mountainous region experiment at the FLUXNET site Waldstein-Weidenbrunnen (DE-Bay). Estimates of NEE including advection are compared to NEE from turbulent and storage flux alone without advection. NEE including vertical advection with sector-wise planar fit rotation and controlled window length and including horizontal advection from continuous gradient measurements, which were comprehensively bias corrected by a new approach, did compare well with the expected night flux error, with meteorological drivers of the fluxes and with soil chamber measurements. Unrealistically large and noisy values of horizontal advection from the conventional discontinuous sampling approach, which lead to unrealistic values of NEE, could be eliminated by the alternative approaches presented. We therefore suggest the further testing of those approaches at other sites in order to improve the accuracy of advection measurements and, subsequently, estimates of NEE. © 2011 Springer-Verlag.  
  Address (up) Wind Cert Services, TÜV SÜD Industrie Service GmbH, Ludwig-Eckert-Str. 10, 93049 Regensburg, Germany  
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  ISSN 0177798x (Issn) ISBN Medium  
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  Notes Export Date: 27 June 2012; Source: Scopus; doi: 10.1007/s00704-011-0552-3; Language of Original Document: English; Correspondence Address: Siebicke, L.; Department of Micrometeorology, University of Bayreuth, Universitätsstr. 30, 95440 Bayreuth, Germany; email: lukas.siebicke@uni-bayreuth.de Approved no  
  Call Number EcoFoG @ webmaster @ Serial 406  
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Author Brémaud, I.; El Kaïm, Y.; Guibal, D.; Minato, K.; Thibaut, B.; Gril, J. url  openurl
  Title Characterisation and categorisation of the diversity in viscoelastic vibrational properties between 98 wood types Type Journal Article
  Year 2012 Publication Annals of Forest Science Abbreviated Journal Ann. Forest Sci.  
  Volume 69 Issue 3 Pages 373-386  
  Keywords Damping coefficient; Dynamic mechanical properties; Specific dynamic modulus of elasticity; Specific gravity; Viscoelastic vibrational properties; Wood diversity  
  Abstract · Context Increased knowledge on diversity in wood properties would have implications both for fundamental research and for promoting a diversification of uses as material. · Aims The objective is to contribute to overcoming the critical lack of data on the diversity of wood dynamic mechanical/viscoelastic vibrational properties by testing lesser known species and categorising sources of variability. · Methods Air-dry axial specific dynamic modulus of elasticity (E′/γ) and damping coefficient (tand) were measured on a wide sampling (1,792 specimens) of 98 wood types from 79 species. An experimental device and protocol was designed for conducting systematic (i.e. rapid and reproducible) characterisations. · Results Diversity at the specimens' level corroborates the “standard” relationship between tanδ and E'/γ, which is discussed in terms of orientation of wood elements and of chemical composition. Diversity at the species level is expressed on the basis of results for normal heartwood, with specific gravity (γ) ranging from 0.2 to 1.3. Axial E'/γ ranges from 9 to 32 GPa and tand from 4×10 -3 to 19×10 -3. Properties distribution follows a continuum, but with group characteristics. The lowest values of tanδ are only found in certain tropical hardwoods. Results can also suggest alternative species for musical instruments making. · Conclusion The variations in specific gravity, in stiffness or in “viscosity” appear to be predominantly linked to different levels of diversity: between species or between wood types (reaction wood or taxonomy-related differences in heartwood extractives). © INRA/Springer-Verlag France 2011.  
  Address (up) Wood Laboratory, EMPA, Überlandstrasse 129, 8600 Dübendorf, Switzerland  
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  ISSN 12864560 (Issn) ISBN Medium  
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  Notes Export Date: 20 June 2012; Source: Scopus; Coden: Afosf; doi: 10.1007/s13595-011-0166-z; Language of Original Document: English; Correspondence Address: Brémaud, I.; Wood Laboratory, EMPA, Überlandstrasse 129, 8600 Dübendorf, Switzerland; email: iris_bremaud@hotmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 403  
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Author Brémaud, I.; Ruelle, J.; Thibaut, A.; Thibaut, B. doi  openurl
  Title Changes in viscoelastic vibrational properties between compression and normal wood: Roles of microfibril angle and of lignin Type Journal Article
  Year 2013 Publication Holzforschung Abbreviated Journal  
  Volume 67 Issue 1 Pages 75-85  
  Keywords Compression wood (CW); Damping coefficient; Ft-Ir; Internal friction; Lignin; Microfibril angle (MFA); Picea abies; Pinus pinaster; Pinus sylvestris; Specific dynamic modulus of elasticity; Viscoelastic vibrational properties  
  Abstract This study aims at better understanding the respective influences of specific gravity (γ ), microfibril angle (MFA), and cell wall matrix polymers on viscoelastic vibrational properties of wood in the axial direction. The wide variations of properties between normal wood (NW) and compression wood (CW) are in focus. Three young bent trees (Picea abies, Pinus sylvestris and Pinus pinaster ), which recovered verticality, were sampled. Several observed differences between NW and CW were highly significant in terms of anatomical, physical (γ, shrinkage, CIE Lab colorimetry), mechanical (compressive strength), and vibrational properties. The specific dynamic modulus of elasticity (E′/γ) decreases with increasing MFA, and Young's modulus (E′) can be satisfactorily explained by γ and MFA. Apparently, the type of the cell wall polymer matrix is not influential in this regard. The damping coefficient (tan δ) does not depend solely on the MFA of NW and CW. The tanδ-E′/γ relationship evidences that, at equivalent E′/γ, the tan δ of CW is approximately 34% lower than that of NW. This observation is ascribed to the more condensed nature of CW lignins, and this is discussed in the context of previous findings in other hygrothermal and time/frequency domains. It is proposed that the lignin structure and the amount and type of extractives, which are both different in various species, are partly responsible for taxonomy-related damping characteristics. Copyright © by Walter de Gruyter • Berlin • Boston.  
  Address (up) Wood Laboratory, Empa-Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland  
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  Notes Export Date: 25 February 2013; Source: Scopus Approved no  
  Call Number EcoFoG @ webmaster @ Serial 471  
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