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Author Bremaud, I.; Cabrolier, P.; Gril, J.; Clair, B.; Gerard, J.; Minato, K.; Thibaut, B. openurl 
  Title Identification of anisotropic vibrational properties of Padauk wood with interlocked grain Type Journal Article
  Year 2010 Publication Wood Science and Technology Abbreviated Journal Wood Sci. Technol.  
  Volume 44 Issue 3 Pages 355-367  
  Keywords (up)  
  Abstract Grain deviations and high extractives content are common features of many tropical woods. This study aimed at clarifying their respective impact on vibrational properties, referring to African Padauk (Pterocarpus soyauxii Taub.), a species selected for its interlocked grain, high extractives content and uses in xylophones. Specimens were cut parallel to the trunk axis (L), and local variations in grain angle (GA), microfibril angle (MFA), specific Young's modulus (E' (L) /rho, where rho stands for the density) and damping coefficient (tan delta(L)) were measured. GA dependence was analysed by a mechanical model which allowed to identify the specific Young's modulus (E'(3)/rho) and shear modulus (G'/rho) along the grain (3) as well as their corresponding damping coefficients (tan delta(3), tan delta(G)). This analysis was done for native and then for extracted wood. Interlocked grain resulted in 0-25A degrees GA and in variations of a factor 2 in E'(L)/rho and tan delta(L). Along the grain, Padauk wood was characterized, when compared to typical hardwoods, by a somewhat lower E'(3)/rho and elastic anisotropy (E'/G'), due to a wide microfibril angle plus a small weight effect of extracts, and a very low tan delta(3) and moderate damping anisotropy (tan delta(G)/tan delta(3)). Extraction affected mechanical parameters in the order: tan delta(3) a parts per thousand tan delta(G) > G'/rho > > E'(3)/rho. That is, extractives' effects were nearly isotropic on damping but clearly anisotropic on storage moduli.  
  Address [Bremaud, Iris; Minato, Kazuya] Kyoto Prefectural Univ, Grad Sch Life & Environm Sci, Lab Forest Resource Circulating Circles, Kyoto 6068522, Japan, Email: iris_bremaud@hotmail.com  
  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 0043-7719 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000280090400001 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 48  
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Author Dejean, A.; Leroy, C.; Corbara, B.; Roux, O.; Cereghino, R.; Orivel, J.; Boulay, R. pdf  openurl
  Title Arboreal Ants Use the "Velcro (R) Principle'' to Capture Very Large Prey Type Journal Article
  Year 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 6 Pages e11331  
  Keywords (up)  
  Abstract Plant-ants live in a mutualistic association with host plants known as "myrmecophytes'' that provide them with a nesting place and sometimes with extra-floral nectar (EFN) and/or food bodies (FBs); the ants can also attend sap-sucking Hemiptera for their honeydew. In return, plant-ants, like most other arboreal ants, protect their host plants from defoliators. To satisfy their nitrogen requirements, however, some have optimized their ability to capture prey in the restricted environment represented by the crowns of trees by using elaborate hunting techniques. In this study, we investigated the predatory behavior of the ant Azteca andreae which is associated with the myrmecophyte Cecropia obtusa. We noted that up to 8350 ant workers per tree hide side-by-side beneath the leaf margins of their host plant with their mandibles open, waiting for insects to alight. The latter are immediately seized by their extremities, and then spread-eagled; nestmates are recruited to help stretch, carve up and transport prey. This group ambush hunting technique is particularly effective when the underside of the leaves is downy, as is the case for C. obtusa. In this case, the hook-shaped claws of the A. andreae workers and the velvet-like structure of the underside of the leaves combine to act like natural Velcro (R) that is reinforced by the group ambush strategy of the workers, allowing them to capture prey of up to 13,350 times the mean weight of a single worker.  
  Address [Dejean, Alain; Leroy, Celine; Roux, Olivier; Orivel, Jerome] CNRS, Ecol Forets Guyane UMR CNRS 8172, Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279140800028 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 56  
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Author Quesada, C.A.; Lloyd, J.; Schwarz, M.; Patino, S.; Baker, T.R.; Czimczik, C.; Fyllas, N.M.; Martinelli, L.; Nardoto, G.B.; Schmerler, J.; Santos, A.J.B.; Hodnett, M.G.; Herrera, R.; Luizao, F.J.; Arneth, A.; Lloyd, G.; Dezzeo, N.; Hilke, I.; Kuhlmann, I.; Raessler, M.; Brand, W.A.; Geilmann, H.; Moraes, J.O.; Carvalho, F.P.; Araujo, R.N.; Chaves, J.E.; Cruz, O.F.; Pimentel, T.P.; Paiva, R. openurl 
  Title Variations in chemical and physical properties of Amazon forest soils in relation to their genesis Type Journal Article
  Year 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 5 Pages 1515-1541  
  Keywords (up)  
  Abstract Soil samples were collected in six South American countries in a total of 71 different 1 ha forest plots across the Amazon Basin as part of the RAINFOR project. They were analysed for total and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties were also examined and an index of soil physical quality proposed. A diverse range of soils was found. For the western areas near the Andean cordillera and the southern and northern fringes, soils tend to be distributed among the lower pedogenetic levels, while the central and eastern areas of Amazonia have more intensely weathered soils. This gives rise to a large variation of soil chemical and physical properties across the Basin, with soil properties varying predictably along a gradient of pedogenic development. Nutrient pools generally increased slightly in concentration from the youngest to the intermediate aged soils after which a gradual decline was observed with the lowest values found in the most weathered soils. Soil physical properties were strongly correlated with soil fertility, with favourable physical properties occurring in highly weathered and nutrient depleted soils and with the least weathered, more fertile soils having higher incidence of limiting physical properties. Soil phosphorus concentrations varied markedly in accordance with weathering extent and appear to exert an important influence on the nitrogen cycle of Amazon forest soils.  
  Address [Quesada, C. A.; Lloyd, J.; Baker, T. R.; Fyllas, N. M.] Univ Leeds, Sch Geog, Earth & Biosphere Inst, Leeds LS2 9JT, W Yorkshire, England, Email: betoquesada@yahoo.com.br  
  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:000278184500011 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 58  
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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 2010 Publication Holzforschung Abbreviated Journal Holzforschung  
  Volume 64 Issue 2 Pages 211-215  
  Keywords (up)  
  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 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 2010 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 7 Issue 1 Pages 43-55  
  Keywords (up)  
  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 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 2010 Publication Journal of Natural Products Abbreviated Journal J. Nat. Prod.  
  Volume 73 Issue 11 Pages 1884-1890  
  Keywords (up)  
  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 Bekaert, E.; Robert, F.; Lippens, P.E.; Menetrier, M. openurl 
  Title Li-7 NMR Knight Shifts in Li-Sn Compounds: MAS NMR Measurements and Correlation with DFT Calculations Type Journal Article
  Year 2010 Publication Journal of Physical Chemistry C Abbreviated Journal J. Phys. Chem. C  
  Volume 114 Issue 14 Pages 6749-6754  
  Keywords (up)  
  Abstract Several Li-Sn crystalline phases, LiSn. Li7Sn3, Li5Sn7, Li13Sn5, Li7Sn2, and Li22Sn5. were prepared by ball-milling and studied by Li-7 MAS NMR spectroscopy with silica as a chiming agent to avoid field penetration limitations All phases except for LiSn exhibit exchanged NMR signals at room temperature for the various types of Li present in the unit cells. in the 10 to 100 ppm range. Electronic structure calculations based on first-principles method led to a lather good correlation between the participation of the Li 2s orbital to the density of states (DOS) at the Fermi level and the corresponding NMR Knight shift for the two Li crystallographic types in the case of LiSn, and for the weighted average of the different crystallographic types in the case of the NMR-exchanged signals for the other compounds  
  Address [Bekaert, Emilie; Menetrier, Michel] Univ Bordeaux, CNRS, ICMCB, F-33608 Pessac, France  
  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 1932-7447 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000276341700075 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 80  
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Author Dejean, A.; Fisher, B.L.; Corbara, B.; Rarevohitra, R.; Randrianaivo, R.; Rajemison, B.; Leponce, M. pdf  openurl
  Title Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence of an Invasive Species Type Journal Article
  Year 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 2 Pages e9319  
  Keywords (up)  
  Abstract We conducted a survey along three belt transects located at increasing distances from the coast to determine whether a non-random arboreal ant assemblage, such as an ant mosaic, exists in the rainforest on the Masoala Peninsula, Madagascar. In most tropical rainforests, very populous colonies of territorially dominant arboreal ant species defend absolute territories distributed in a mosaic pattern. Among the 29 ant species recorded, only nine had colonies large enough to be considered potentially territorially dominant; the remaining species had smaller colonies and were considered non-dominant. Nevertheless, the null-model analyses used to examine the spatial structure of their assemblages did not reveal the existence of an ant mosaic. Inland, up to 44% of the trees were devoid of dominant arboreal ants, something not reported in other studies. While two Crematogaster species were not associated with one another, Brachymyrmex cordemoyi was positively associated with Technomyrmex albipes, which is considered an invasive species-a non-indigenous species that has an adverse ecological effect on the habitats it invades. The latter two species and Crematogaster ranavalonae were mutually exclusive. On the other hand, all of the trees in the coastal transect and at least 4 km of coast were occupied by T. albipes, and were interconnected by columns of workers. Technomyrmex albipes workers collected from different trees did not attack each other during confrontation tests, indicating that this species has formed a supercolony along the coast. Yet interspecific aggressiveness did occur between T. albipes and Crematogaster ranavalonae, a native species which is likely territorially dominant based on our intraspecific confrontation tests. These results suggest that the Masoala rainforest is threatened by a potential invasion by T. albipes, and that the penetration of this species further inland might be facilitated by the low density of native, territorially dominant arboreal ants normally able to limit its progression.  
  Address [Dejean, Alain] CNRS, Unite Mixte Rech 8172, Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274923700021 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 81  
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Author Roux, O.; Billen, J.; Orivel, J.; Dejean, A. pdf  openurl
  Title An Overlooked Mandibular-Rubbing Behavior Used during Recruitment by the African Weaver Ant, Oecophylla longinoda Type Journal Article
  Year 2010 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 5 Issue 2 Pages e8957  
  Keywords (up)  
  Abstract In Oecophylla, an ant genus comprising two territorially dominant arboreal species, workers are known to (1) use anal spots to mark their territories, (2) drag their gaster along the substrate to deposit short-range recruitment trails, and (3) drag the extruded rectal gland along the substrate to deposit the trails used in long-range recruitment. Here we study an overlooked but important marking behavior in which O. longinoda workers first rub the underside of their mandibles onto the substrate, and then-in a surprising posture-tilt their head and also rub the upper side of their mandibles. We demonstrate that this behavior is used to recruit nestmates. Its frequency varies with the rate at which a new territory, a sugary food source, a prey item, or an alien ant are discovered. Microscopy analyses showed that both the upper side and the underside of the mandibles possess pores linked to secretory glands. So, by rubbing their mandibles onto the substrate, the workers probably spread a secretion from these glands that is involved in nestmate recruitment.  
  Address [Roux, Olivier; Dejean, Alain] CNRS, UMR, Kourou, France, Email: oroux@cict.fr  
  Corporate Author Thesis  
  Publisher PUBLIC LIBRARY SCIENCE Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274209700003 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 82  
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Author Fyllas, N.M.; Patino, S.; Baker, T.R.; Nardoto, G.B.; Martinelli, L.A.; Quesada, C.A.; Paiva, R.; Schwarz, M.; Horna, V.; Mercado, L.M.; Santos, A.; Arroyo, L.; Jimenez, E.M.; Luizao, F.J.; Neill, D.A.; Silva, N.; Prieto, A.; Rudas, A.; Silviera, M.; Vieira, I.C.G.; Lopez-Gonzalez, G.; Malhi, Y.; Phillips, O.L.; Lloyd, J. openurl 
  Title Basin-wide variations in foliar properties of Amazonian forest: phylogeny, soils and climate Type Journal Article
  Year 2009 Publication Biogeosciences Abbreviated Journal Biogeosciences  
  Volume 6 Issue 11 Pages 2677-2708  
  Keywords (up)  
  Abstract We analysed 1040 individual trees, located in 62 plots across the Amazon Basin for leaf mass per unit area (M-A), foliar carbon isotopic composition (delta C-13) and leaf level concentrations of C, N, P, Ca, Mg, K and Al. All trees were identified to the species level with the dataset containing 58 families, 236 genera and 508 species, distributed across a wide range of soil types and precipitation regimes. Some foliar characteristics such as M-A, [C], [N] and [Mg] emerge as highly constrained by the taxonomic affiliation of tree species, but with others such as [P], [K], [Ca] and delta C-13 also strongly influenced by site growing conditions. By removing the environmental contribution to trait variation, we find that intrinsic values of most trait pairs coordinate, although different species ( characterised by different trait suites) are found at discrete locations along a common axis of coordination. Species that tend to occupy higher fertility soils are characterised by a lower M-A and have a higher intrinsic [N], [P], [K], [Mg] and delta C-13 than their lower fertility counterparts. Despite this consistency, different scaling patterns were observed between low and high fertility sites. Inter-relationships are thus substantially modified by growth environment. Analysing the environmental component of trait variation, we found soil fertility to be the most important predictor, influencing all leaf nutrient concentrations and delta C-13 and reducing M-A. Mean annual temperature was negatively associated with leaf level [N], [P] and [K] concentrations. Total annual precipitation positively influences M-A, [C] and delta C-13, but with a negative impact on [Mg]. These results provide a first basis for understanding the relationship between the physiological functioning and distribution of tree species across Amazonia.  
  Address [Fyllas, N. M.; Baker, T. R.; Quesada, C. A.; Lopez-Gonzalez, G.; Phillips, O. L.; Lloyd, J.] Univ Leeds, Sch Geog, Earth & Biosphere Inst, Leeds LS2 9JT, W Yorkshire, England, Email: n.fyllas@leeds.ac.uk  
  Corporate Author Thesis  
  Publisher COPERNICUS PUBLICATIONS 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:000272232200025 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 92  
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