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Author Freycon, V.; Krencker, M.; Schwartz, D.; Nasi, R.; Bonal, D. openurl 
  Title The impact of climate changes during the Holocene on vegetation in northern French Guiana Type Journal Article
  Year (up) 2010 Publication Quaternary Research Abbreviated Journal Quat. Res.  
  Volume 73 Issue 2 Pages 220-225  
  Keywords Holocene; Vegetation change; French Guiana; Carbon isotope composition; Soil organic matter  
  Abstract The impact of climatic changes that occurred during the last glacial maximum and the Holocene on vegetation changes in the Amazon Basin and the Guiana Shield are still widely debated. The aim of our study was to investigate whether major changes in vegetation (i.e. transitions between rainforests and C-4 savannas) occurred in northern French Guiana during the Holocene. We measured variations in the delta C-13 of soil organic matter at eight sites now occupied by forest or savannah. The forest sites were selected to cover two regions (forest refugia and peneplains) which are thought to have experienced different intensities of disturbance during the latest Pleistocene and the Holocene. We found that none of the forest sites underwent major disturbances during the Holocene, i.e. they were not replaced by C-4 savannahs or C-4 forest savannahs for long periods. Our results thus suggest that tropical rainforests in northern French Guiana were resilient to drier climatic conditions during the Holocene. Nevertheless, geographical and vertical variations in the C-13 of SOM were compatible with minor changes in vegetation, variations in soil processes or in soil physical properties. (C) 2009 University of Washington. Published by Elsevier Inc. All rights reserved.  
  Address [Freycon, Vincent] CIRAD, UR Dynam Forestiere, F-34398 Montpellier 5, France, Email: vincent.freycon@cirad.fr  
  Corporate Author Thesis  
  Publisher ACADEMIC PRESS INC ELSEVIER SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0033-5894 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000275246700007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 66  
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Author Royer, M.; Stien, D.; Beauchene, J.; Herbette, G.; McLean, J.P.; Thibaut, A.; Thibaut, B. openurl 
  Title Extractives of the tropical wood wallaba (Eperua falcata Aubl.) as natural anti-swelling agents Type Journal Article
  Year (up) 2010 Publication Holzforschung Abbreviated Journal Holzforschung  
  Volume 64 Issue 2 Pages 211-215  
  Keywords  
  Abstract Wallaba (Eperua falcata) is a tropical wood that is known to have naturally high moisture related dimensional stability. Samples of wallaba heartwood were subjected to differential solvent extraction. Wood pieces that were extracted with methanol showed significantly greater swelling following rehydration from oven dry to 96% relative humidity than non- extracted samples and samples extracted with other solvents. Methanol soluble wallaba heartwood extract was purified by HPLC and the compounds present were characterized by NMR spectroscopy. The structure of 13 compounds in methanol extract was identified. The relative proportion of polar compounds in methanol extract was found to be high. The compounds identified are proposed to bind to the polymeric cell wall by means of multiple hydrogen bonds restricting the association of water and therefore act as natural anti-swelling agents.  
  Address  
  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 0018-3830 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000274423900010 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 307  
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Author Scotti, I.; Calvo-Vialettes, L.; Scotti-Saintagne, C.; Citterio, M.; Degen, B.; Bonal, D. openurl 
  Title Genetic variation for growth, morphological, and physiological traits in a wild population of the Neotropical shade tolerant rainforest tree Sextonia rubra (Mez) van der Werff (Lauraceae) Type Journal Article
  Year (up) 2010 Publication Tree Genetics & Genomes Abbreviated Journal Tree Genet. Genomes  
  Volume 6 Issue 2 Pages 319-329  
  Keywords Ecophysiological traits; Heritability; Guiana shield; Amazon; Ecological genetics  
  Abstract Quantitative genetic diversity is a fundamental component of the interaction between natural populations and their environment. In breeding programmes, quantitative genetic studies on tropical trees have so far focused on fast-growing, light-demanding species, but no information exists on shade-tolerant, slow-growing species. For this study, 27 3-year-old open-pollinated families of the Neotropical shade-tolerant rainforest tree Sextonia rubra were measured in semicontrolled conditions for 20 morphological, growth, and photosynthesis traits; the effect of genetic relatedness, habitat of provenance, and mother tree status on seedling traits was analysed. Nine traits displayed significant genetic effects, while mother tree status and habitat effects were not significant (P > 0.05) for an y trait. Estimated heritability varied between 0.14 and 0.28, with growth-related traits having the highest values. Additive genetic variation correlated positively with nonheritable variation, suggesting that ecological-evolutionary factors increasing or decreasing additive genetic variance may also affect nonheritable variation in the same direction. Our results suggest that quantitative genetic variability should be taken into account in ecological studies on, and in the management of, natural tropical rainforests; further research is needed to investigate genetic x environment interactions, in particular from the point of view of the genetic response of shade-tolerant plant species to variations in light availability.  
  Address [Scotti, Ivan; Scotti-Saintagne, Caroline; Bonal, Damien] INRA, Unite Mixte Rech Ecol Forets Guyane, Kourou 97387, French Guiana, Email: ivan.scotti@ecofog.gf  
  Corporate Author Thesis  
  Publisher SPRINGER HEIDELBERG Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1614-2942 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274112600015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 68  
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Author Schwalm, C.R.; Williams, C.A.; Schaefer, K.; Arneth, A.; Bonal, D.; Buchmann, N.; Chen, J.Q.; Law, B.E.; Lindroth, A.; Luyssaert, S.; Reichstein, M.; Richardson, A.D. openurl 
  Title Assimilation exceeds respiration sensitivity to drought: A FLUXNET synthesis Type Journal Article
  Year (up) 2010 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.  
  Volume 16 Issue 2 Pages 657-670  
  Keywords biome; carbon cycling; drought; eddy covariance; evaporative fraction; FLUXNET; synthesis  
  Abstract The intensification of the hydrological cycle, with an observed and modeled increase in drought incidence and severity, underscores the need to quantify drought effects on carbon cycling and the terrestrial sink. FLUXNET, a global network of eddy covariance towers, provides dense data streams of meteorological data, and through flux partitioning and gap filling algorithms, estimates of net ecosystem productivity (F-NEP), gross ecosystem productivity (P), and ecosystem respiration (R). We analyzed the functional relationship of these three carbon fluxes relative to evaporative fraction (EF), an index of drought and site water status, using monthly data records from 238 micrometeorological tower sites distributed globally across 11 biomes. The analysis was based on relative anomalies of both EF and carbon fluxes and focused on drought episodes by biome and climatic season. Globally P was approximate to 50% more sensitive to a drought event than R. Network-wide drought-induced decreases in carbon flux averaged -16.6 and -9.3 g C m-2 month-1 for P and R, i.e., drought events induced a net decline in the terrestrial sink. However, in evergreen forests and wetlands drought was coincident with an increase in P or R during parts of the growing season. The most robust relationships between carbon flux and EF occurred during climatic spring for F-NEP and in climatic summer for P and R. Upscaling flux sensitivities to a global map showed that spatial patterns for all three carbon fluxes were linked to the distribution of croplands. Agricultural areas exhibited the highest sensitivity whereas the tropical region had minimal sensitivity to drought. Combining gridded flux sensitivities with their uncertainties and the spatial grid of FLUXNET revealed that a more robust quantification of carbon flux response to drought requires additional towers in all biomes of Africa and Asia as well as in the cropland, shrubland, savannah, and wetland biomes globally.  
  Address [Schwalm, Christopher R.; Williams, Christopher A.] Clark Univ, Grad Sch Geog, Worcester, MA 01610 USA, Email: cschwalm@clarku.edu  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1354-1013 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274419400014 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 69  
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Author Chave, J.; Navarrete, D.; Almeida, S.; Alvarez, E.; Aragao, L.E.O.C.; Bonal, D.; Chatelet, P.; Silva-Espejo, J.E.; Goret, J.Y.; von Hildebrand, P.; Jimenez, E.; Patino, S.; Penuela, M.C.; Phillips, O.L.; Stevenson, P.; Malhi, Y. openurl 
  Title Regional and seasonal patterns of litterfall in tropical South America Type Journal Article
  Year (up) 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 1 Pages 43-55  
  Keywords  
  Abstract The production of aboveground soft tissue represents an important share of total net primary production in tropical rain forests. Here we draw from a large number of published and unpublished datasets (n=81 sites) to assess the determinants of litterfall variation across South American tropical forests. We show that across old-growth tropical rainforests, litterfall averages 8.61 +/- 1.91 Mg ha(-1) yr(-1) (mean +/- standard deviation, in dry mass units). Secondary forests have a lower annual litterfall than old-growth tropical forests with a mean of 8.01 +/- 3.41 Mg ha(-1) yr(-1). Annual litterfall shows no significant variation with total annual rainfall, either globally or within forest types. It does not vary consistently with soil type, except in the poorest soils (white sand soils), where litterfall is significantly lower than in other soil types (5.42 +/- 1.91 Mg ha(-1) yr(-1)). We also study the determinants of litterfall seasonality, and find that it does not depend on annual rainfall or on soil type. However, litterfall seasonality is significantly positively correlated with rainfall seasonality. Finally, we assess how much carbon is stored in reproductive organs relative to photosynthetic organs. Mean leaf fall is 5.74 +/- 1.83 Mg ha(-1) yr(-1) (71% of total litterfall). Mean allocation into reproductive organs is 0.69 +/- 0.40 Mg ha(-1) yr(-1) (9% of total litterfall). The investment into reproductive organs divided by leaf litterfall increases with soil fertility, suggesting that on poor soils, the allocation to photosynthetic organs is prioritized over that to reproduction. Finally, we discuss the ecological and biogeochemical implications of these results.  
  Address [Chave, J.] CNRS UPS, Lab Evolut & Divers Biol, UMR 5174, Toulouse, France, Email: chave@cict.fr  
  Corporate Author Thesis  
  Publisher COPERNICUS GESELLSCHAFT MBH Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1726-4170 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274058100004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 70  
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Author Coutand, C.; Chevolot, M.; Lacointe, A.; Rowe, N.; Scotti, I. openurl 
  Title Mechanosensing of stem bending and its interspecific variability in five neotropical rainforest species Type Journal Article
  Year (up) 2010 Publication Annals of Botany Abbreviated Journal Ann. Bot.  
  Volume 105 Issue 2 Pages 341-347  
  Keywords Mechanosensing; interspecific variability; trees; lianas; rain forest; neotropical species; bending; biomechanics; Bauhinia; Eperua; Symphonia; Tachigali  
  Abstract In rain forests, sapling survival is highly dependent on the regulation of trunk slenderness (height/diameter ratio): shade-intolerant species have to grow in height as fast as possible to reach the canopy but also have to withstand mechanical loadings (wind and their own weight) to avoid buckling. Recent studies suggest that mechanosensing is essential to control tree dimensions and stability-related morphogenesis. Differences in species slenderness have been observed among rainforest trees; the present study thus investigates whether species with different slenderness and growth habits exhibit differences in mechanosensitivity. Recent studies have led to a model of mechanosensing (sum-of-strains model) that predicts a quantitative relationship between the applied sum of longitudinal strains and the plant's responses in the case of a single bending. Saplings of five different neotropical species (Eperua falcata, E. grandiflora, Tachigali melinonii, Symphonia globulifera and Bauhinia guianensis) were subjected to a regimen of controlled mechanical loading phases (bending) alternating with still phases over a period of 2 months. Mechanical loading was controlled in terms of strains and the five species were subjected to the same range of sum of strains. The application of the sum-of-strain model led to a dose-response curve for each species. Dose-response curves were then compared between tested species. The model of mechanosensing (sum-of-strain model) applied in the case of multiple bending as long as the bending frequency was low. A comparison of dose-response curves for each species demonstrated differences in the stimulus threshold, suggesting two groups of responses among the species. Interestingly, the liana species B. guianensis exhibited a higher threshold than other Leguminosae species tested. This study provides a conceptual framework to study variability in plant mechanosensing and demonstrated interspecific variability in mechanosensing.  
  Address [Coutand, Catherine; Lacointe, Andre] Univ Clermont Ferrand, INRA, PIAF, UMR 547, F-63000 Clermont Ferrand, France, Email: coutand@clermont.inra.fr  
  Corporate Author Thesis  
  Publisher OXFORD UNIV PRESS Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0305-7364 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274347000025 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 71  
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Author Baraloto, C.; Paine, C.E.T.; Patino, S.; Bonal, D.; Herault, B.; Chave, J. openurl 
  Title Functional trait variation and sampling strategies in species-rich plant communities Type Journal Article
  Year (up) 2010 Publication Functional Ecology Abbreviated Journal Funct. Ecol.  
  Volume 24 Issue 1 Pages 208-216  
  Keywords French Guiana; functional diversity; plant traits; specific leaf area; wood density; sampling design; tropical forest  
  Abstract P> Despite considerable interest in the application of plant functional traits to questions of community assembly and ecosystem structure and function, there is no consensus on the appropriateness of sampling designs to obtain plot-level estimates in diverse plant communities. We measured 10 plant functional traits describing leaf and stem morphology and ecophysiology for all trees in nine 1-ha plots in terra firme lowland tropical rain forests of French Guiana (N = 4709). We calculated, by simulation, the mean and variance in trait values for each plot and each trait expected under seven sampling methods and a range of sampling intensities. Simulated sampling methods included a variety of spatial designs, as well as the application of existing data base values to all individuals of a given species. For each trait in each plot, we defined a performance index for each sampling design as the proportion of resampling events that resulted in observed means within 5% of the true plot mean, and observed variance within 20% of the true plot variance. The relative performance of sampling designs was consistent for estimations of means and variances. Data base use had consistently poor performance for most traits across all plots, whereas sampling one individual per species per plot resulted in relatively high performance. We found few differences among different spatial sampling strategies; however, for a given strategy, increased intensity of sampling resulted in markedly improved accuracy in estimates of trait mean and variance. We also calculated the financial cost of each sampling design based on data from our 'every individual per plot' strategy and estimated the sampling and botanical effort required. The relative performance of designs was strongly positively correlated with relative financial cost, suggesting that sampling investment returns are relatively constant. Our results suggest that trait sampling for many objectives in species-rich plant communities may require the considerable effort of sampling at least one individual of each species in each plot, and that investment in complete sampling, though great, may be worthwhile for at least some traits.  
  Address [Baraloto, Christopher; Patino, Sandra; Bonal, Damien] INRA, UMR Ecol Forets Guyane, F-97387 Kourou, French Guiana, Email: chris.baraloto@ecofog.gf  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000273455500024 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 72  
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Author Cabanillas, B.J.; Le Lamer, A.C.; Castillo, D.; Arevalo, J.; Rojas, R.; Odonne, G.; Bourdy, G.; Moukarzel, B.; Sauvain, M.; Fabre, N. openurl 
  Title Caffeic Acid Esters and Lignans from Piper sanguineispicum Type Journal Article
  Year (up) 2010 Publication Journal of Natural Products Abbreviated Journal J. Nat. Prod.  
  Volume 73 Issue 11 Pages 1884-1890  
  Keywords  
  Abstract Three new caffeic acid esters (1-3), four new lignans (4-7), and the known compounds (7'S)-parabenzlactone (8), dihydrocubebin (9), and justiflorinol (10) have been isolated from leaves of Piper sanguineispicum. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRCIMS, CD experiments, and chemical methods. Compounds 1-10 were assessed for their antileishmanial potential against axenic amastigote forms of Leishmania amazonensis. Caffeic acid esters 1 and 3 exhibited the best antileishmanial activity (IC50 2.0 and 1.8 μM, respectively) with moderate cytotoxicity on murine macrophages.  
  Address [Cabanillas, Billy Joel; Le Lamer, Anne-Cecile; Odonne, Guillaume; Bourdy, Genevieve; Moukarzel, Beatrice; Sauvain, Michel; Fabre, Nicolas] Univ Toulouse, UPS, UMR 152, Lab Pharmacochim Subst Nat & Pharmacophores Redox, F-31062 Toulouse 9, France, Email: michel.sauvain@ird.fr  
  Corporate Author Thesis  
  Publisher AMER CHEMICAL SOC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-3864 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284559100024 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 74  
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Author Dejean, A.; Leroy, C.; Corbara, B.; Cereghino, R.; Roux, O.; Herault, B.; Rossi, V.; Guerrero, R.J.; Delabie, J.H.C.; Orivel, J.; Boulay, R. openurl 
  Title A temporary social parasite of tropical plant-ants improves the fitness of a myrmecophyte Type Journal Article
  Year (up) 2010 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 97 Issue 10 Pages 925-934  
  Keywords Ant-plant relationships; Biotic defense; Parasites of mutualisms; Temporary social parasites; Azteca; Cecropia  
  Abstract Myrmecophytes offer plant-ants a nesting place in exchange for protection from their enemies, particularly defoliators. These obligate ant-plant mutualisms are common model systems for studying factors that allow horizontally transmitted mutualisms to persist since parasites of ant-myrmecophyte mutualisms exploit the rewards provided by host plants whilst providing no protection in return. In pioneer formations in French Guiana, Azteca alfari and Azteca ovaticeps are known to be mutualists of myrmecophytic Cecropia (Cecropia ants). Here, we show that Azteca andreae, whose colonies build carton nests on myrmecophytic Cecropia, is not a parasite of Azteca-Cecropia mutualisms nor is it a temporary social parasite of A. alfari; it is, however, a temporary social parasite of A. ovaticeps. Contrarily to the two mutualistic Azteca species that are only occasional predators feeding mostly on hemipteran honeydew and food bodies provided by the host trees, A. andreae workers, which also attend hemipterans, do not exploit the food bodies. Rather, they employ an effective hunting technique where the leaf margins are fringed with ambushing workers, waiting for insects to alight. As a result, the host trees' fitness is not affected as A. andreae colonies protect their foliage better than do mutualistic Azteca species resulting in greater fruit production. Yet, contrarily to mutualistic Azteca, when host tree development does not keep pace with colony growth, A. andreae workers forage on surrounding plants; the colonies can even move to a non-Cecropia tree.  
  Address [Dejean, Alain; Leroy, Celine; Roux, Olivier; Orivel, Jerome] CNRS, F-97379 Kourou, France, Email: alain.dejean@wanadoo.fr  
  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 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000282094100006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 77  
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Author Foucaud, J.; Estoup, A.; Loiseau, A.; Rey, O.; Orivel, J. openurl 
  Title Thelytokous parthenogenesis, male clonality and genetic caste determination in the little fire ant: new evidence and insights from the lab Type Journal Article
  Year (up) 2010 Publication Heredity Abbreviated Journal Heredity  
  Volume 105 Issue 2 Pages 205-212  
  Keywords reproduction system; thelytokous parthenogenesis; male clonality; genetic caste determination; Wasmannia auropunctata  
  Abstract Previous studies indicate that some populations of the little fire ant, Wasmannia auropunctata, display an unusual reproduction system polymorphism. Although some populations have a classical haplodiploid reproduction system, in other populations queens are produced by thelytokous parthenogenesis, males are produced by a male clonality system and workers are produced sexually. An atypical genetic caste determination system was also suggested. However, these conclusions were indirectly inferred from genetic studies on field population samples. Here we set up experimental laboratory nests that allow the control of the parental relationships between individuals. The queens heading those nests originated from either putatively clonal or sexual populations. We characterized the male, queen and worker offspring they produced at 12 microsatellite loci. Our results unambiguously confirm the unique reproduction system polymorphism mentioned above and that male clonality is strictly associated with thelytokous parthenogenesis. We also observed direct evidence of the rare production of sexual gynes and arrhenotokous males in clonal populations. Finally, we obtained evidence of a genetic basis for caste determination. The evolutionary significance of the reproduction system polymorphism and genetic caste determination as well as future research opportunities are discussed. Heredity (2010) 105, 205-212; doi: 10.1038/hdy.2009.169; published online 25 November 2009  
  Address [Foucaud, J.; Estoup, A.; Loiseau, A.; Rey, O.] INRA, UMR CBGP, IRD, Cirad,Montpellier SupAgro, Montferrier Sur Lez, France, Email: julien.foucaud@legs.cnrs-gif.fr  
  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 0018-067X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000280111800007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 78  
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