| Records |
| Author |
Marchal, R.; Mothe, F.; Denaud, L.E.; Thibaut, B.; Bleron, L. |
| Title |
Cutting forces in wood machining – Basics and applications in industrial processes. A review COST Action E35 2004-2008: Wood machining – micromechanics and fracture |
Type |
Journal Article |
| Year |
2009 |
Publication |
Holzforschung |
Abbreviated Journal |
Holzforschung |
| Volume |
63 |
Issue |
2 |
Pages  |
157-167 |
| Keywords |
cutting forces; online control; peeling process; physico-mechanical model; sound; vibrations; wood industry; wood machining |
| Abstract |
The data available in the literature concerning wood cutting forces permits to build models or to simulate the main wood machining processes ( milling, sawing, peeling, etc.). This approach contributes to a better understanding of formation of wood surfaces and chips and the data may be helpful to optimise cutting geometry, reduce tool wear, improve tool material, and to size tool-machines. The models may also be useful for industrial application in two ways: ( 1) providing data to optimise the settings for a given operation ( batch approach), and ( 2) building predictive models that could be the basis of an online control system for the machining processes ( interactive approach). A prerequisite for this is that numerous machining tests on different wood materials are performed based on experiences with different kind of tools and experimental devices. With a focus on potential industrial applications, the emphasis of this review was on the wood peeling process, which is a very demanding special case of wood cutting. Although not so many industrial machines are equipped with expensive force sensors, there is a lot of high quality information available about cutting forces which may be useful to improve the scientific or technological knowledge in wood machining. Alternative parameters, such as vibration or sound measurements, appear to be promising substitutes in the praxis, particularly to feed online control systems of any wood cutting process. |
| Address |
[Marchal, Remy; Bleron, Laurent] Arts & Metiers ParisTech, LABOMAP, F-71250 Cluny, France, Email: remy.marchal@cluny.ensam.fr |
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WALTER DE GRUYTER & CO |
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0018-3830 |
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ISI:000263932200006 |
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EcoFoG @ eric.marcon @ |
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205 |
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Bertani, S.; Houel, E.; Stien, D.; Chevolot, L.; Jullian, V.; Garavito, G.; Bourdy, G.; Deharo, E. |
| Title |
Simalikalactone D is responsible for the antimalarial properties of an amazonian traditional remedy made with Quassia amara L. (Simaroubaceae) |
Type |
Journal Article |
| Year |
2006 |
Publication |
Journal of Ethnopharmacology |
Abbreviated Journal |
J. Ethnopharmacol. |
| Volume |
108 |
Issue |
1 |
Pages |
155-157 |
| Keywords |
antimalarial; Quassia amara; quassinoids; simalikalactone D; traditional medicine |
| Abstract |
French Guiana (North-East Amazonia) records high malaria incidence rates. The traditional antimalarial remedy most widespread there is a simple tea made out from Quassia amara L. leaves (Simaroubaceae). This herbal tea displays an excellent antimalarial activity both in vitro and in vivo. A known quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC50 value of 10 nM against FeB1 Plasmodium falciparum chloroquine resistant strain in vitro. Lastly, it inhibits 50% of Plasmodium yoelii yoelii rodent malaria parasite at 3.7 mg/kg/day in vivo by oral route. These findings confirm the traditional use of this herbal tea. (c) 2006 Elsevier Ireland Ltd. All rights reserved. |
| Address |
Univ Toulouse 3, UMR 152, Ctr IRD, F-97323 Cayenne, French Guiana, Email: deharo@cayenne.ird.fr |
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| Publisher |
ELSEVIER IRELAND LTD |
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0378-8741 |
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ISI:000241573000023 |
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EcoFoG @ eric.marcon @ |
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173 |
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Stahl, C.; Burban, B.; Wagner, F.; Goret, J.-Y.; Bompy, F.; Bonal, D. |
| Title |
Influence of Seasonal Variations in Soil Water Availability on Gas Exchange of Tropical Canopy Trees |
Type |
Journal Article |
| Year |
2013 |
Publication |
Biotropica |
Abbreviated Journal |
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| Volume |
45 |
Issue |
2 |
Pages |
155-164 |
| Keywords |
French Guiana; Photosynthesis; Predawn leaf water potential; Rain forest; Relative extractable water; Respiration; Soil drought; Transpiration |
| Abstract |
Seasonal variations in environmental conditions influence the functioning of the whole ecosystem of tropical rain forests, but as yet little is known about how such variations directly influence the leaf gas exchange and transpiration of individual canopy tree species. We examined the influence of seasonal variations in relative extractable water in the upper soil layers on predawn leaf water potential, saturated net photosynthesis, leaf dark respiration, stomatal conductance, and tree transpiration of 13 tropical rain forest canopy trees (eight species) over 2 yr in French Guiana. The canopies were accessed by climbing ropes attached to the trees and to a tower. Our results indicate that a small proportion of the studied trees were unaffected by soil water depletion during seasonal dry periods, probably thanks to efficient deep root systems. The trees showing decreased tree water status (i.e., predawn leaf water potential) displayed a wide range of leaf gas exchange responses. Some trees strongly regulated photosynthesis and transpiration when relative extractable water decreased drastically. In contrast, other trees showed little variation, thus indicating good adaptation to soil drought conditions. These results have important applications to modeling approaches: indeed, precise evaluation and grouping of these response patterns are required before any tree-based functional models can efficiently describe the response of tropical rain forest ecosystems to future changes in environmental conditions. © 2012 by The Association for Tropical Biology and Conservation. |
| Address |
INRA, UMR 1137 Université de Lorraine, INRA Nancy 'Ecologie et Ecophysiologie Forestière', Champenoux 54280, France |
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Export Date: 13 March 2013; Source: Scopus |
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no |
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EcoFoG @ webmaster @ |
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474 |
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Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S. |
| Title |
Clustering species using a model of population dynamics and aggregation theory |
Type |
Journal Article |
| Year |
2010 |
Publication |
Ecological Modelling |
Abbreviated Journal |
Ecol. Model. |
| Volume |
221 |
Issue |
2 |
Pages |
152-160 |
| Keywords |
Aggregation theory; Species grouping; Species richness; Tropical rainforest; Usher model |
| Abstract |
The high species diversity of some ecosystems like tropical rainforests goes in pair with the scarcity of data for most species. This hinders the development of models that require enough data for fitting. The solution commonly adopted by modellers consists in grouping species to form more sizeable data sets. Classical methods for grouping species such as hierarchical cluster analysis do not take account of the variability of the species characteristics used for clustering. In this study a clustering method based on aggregation theory is presented. It takes account of the variability of species characteristics by searching for the grouping that minimizes the quadratic error (square bias plus variance) of some model's prediction. This method allows one to check whether the gain in variance brought by data pooling compensate for the bias that it introduces. This method was applied to a data set on 94 tree species in a tropical rainforest in French Guiana, using a Usher matrix model to predict species dynamics. An optimal trade-off between bias and variance was found when grouping species. Grouping species appeared to decrease the quadratic error, except when the number of groups was very small. This clustering method yielded species groups similar to those of the hierarchical cluster analysis using Ward's method when variance was small, that is when the number of groups was small. (C) 2009 Elsevier B.V. All rights reserved. |
| Address |
[Picard, Nicolas; Mortier, Frederic; Rossi, Vivien; Gourlet-Fleury, Sylvie] CIRAD, F-34398 Montpellier 5, France, Email: nicolas.picard@cirad.fr |
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ELSEVIER SCIENCE BV |
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Edition |
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0304-3800 |
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| Notes |
ISI:000273628800004 |
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no |
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EcoFoG @ eric.marcon @ |
Serial |
85 |
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Alméras, T.; Gronvold, A.; van der Lee, A.; Clair, B.; Montero, C. |
| 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 |
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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 |
CNRS, UMR Ecologie des Forêts de Guyane (EcoFoG), AgroParisTech, Cirad, INRA, Université des Antilles, Université de Guyane, Kourou, France |
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Export Date: 26 December 2016 |
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no |
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EcoFoG @ webmaster @ |
Serial |
701 |
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| Author |
Odonne, G.; Bourdy, G.; Castillo, D.; Estevez, Y.; Lancha-Tangoa, A.; Alban-Castillo, J.; Deharo, E.; Rojas, R.; Stien, D.; Sauvain, M. |
| Title |
Ta'ta', Huayani: Perception of leishmaniasis and evaluation of medicinal plants used by the Chayahuita in Peru. Part II |
Type |
Journal Article |
| Year |
2009 |
Publication |
Journal of Ethnopharmacology |
Abbreviated Journal |
J. Ethnopharmacol. |
| Volume |
126 |
Issue |
1 |
Pages |
149-158 |
| Keywords |
Leishmaniasis; Medicinal plants; Traditional medicine; Chayahuita; Peru |
| Abstract |
Aim of the study v: A knowledge attitude and practice study centred on leishmaniasis and its treatment was performed among the Chayahuita, in Amazonian Peruvian ethnic group living in ail endemic area. This study documents traditional Chayahuita plant's use and disease concepts. Also, activity of some medicinal Plants Used by the Chayahuita is highlighted and discussed. Materials and methods: Ninety-three Chayahuita people were interviewed, following a semi-structured questionnaire focussed oil disease knowledge and perception, personal attitude and healing practices. Simultaneously, a collection of plants was performed in different ecotopes, in order to make ail extensive inventory of the pharmacopoeia. Results: For the Chayahuita, cutaneous (CL) and muco-cutaneous leishmaniasis (MCL) are considered as diseases of their own, with specific names, aetiologics, mode of transmission. Regarding CL, Chayahuita people consider that the humid characteristic of the Skill ulcer is a discriminative fact orienting the diagnostic for Ta'ta' (leishmaniasis). Forty-six different species were designated useful against LC and /or MCL (29 species by means of the questionnaire and 27 species when collecting in different ecotopes). Thirty-seven extracts corresponding to 31 Species used medicinally were screened in vitro against Leishmania amazonensis axenic amastigotes, assessing their viability by the reduction Of tetrazolium salt (MTT). Six species displayed a good activity (10 μg/ml < IC50 < 20 μg/ml): all undetermined hemi-epiphytic Clusiaceae. Cybianthus anthuriophyllus Pipoly (Myrsinaceae), two Piper, Piper sanguineispicum Trel., and Piper loretoanum Trel. (Piperaceae), Desmodium axillare Sw. DC. (Fabaceae), and Clibadium sylvestre (Aubl.) Baill (Asteraceae). Conclusion: Perception of leishmaniasis, attitude. treatments and diet prohibitions still largely reflects traditional Chayahuita cosmovision, even if some tentative of bio-medical re-interpretation is arising. (C) 2009 Elsevier Ireland Ltd. All rights reserved. |
| Address |
[Odonne, G.; Bourdy, G.; Estevez, Y.; Deharo, E.; Sauvain, M.] Univ Toulouse, UPS, UMR 152, Lab Pharmacochim Subst Nat & Pharmacophores Redox, F-31062 Toulouse 9, France, Email: Genevieve.bourdy@ird.fr |
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ELSEVIER IRELAND LTD |
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0378-8741 |
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ISI:000271790800020 |
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no |
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EcoFoG @ eric.marcon @ |
Serial |
95 |
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Delaval, M.; Henry, M.; Charles-Dominique, P. |
| Title |
Interspecific competition and niche partitioning: Example of a neotropical rainforest bat community |
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Journal Article |
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2005 |
Publication |
Revue d'Ecologie (La Terre et la Vie) |
Abbreviated Journal |
Rev. Ecol.-Terre Vie |
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60 |
Issue |
2 |
Pages |
149-165 |
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To understand the organization of a bat community and the coexistence of sympatric species, it is essential to understand how species use and share common resources. First, we describe a bat community in a primary rainforest of French Guiana. The presence of particular roosting sites, such as caves, and the absence of disturbances are important local factors in structuring communities. In the course of this study, we focused on the three most common species of three vegetarian bat guilds (understorey frugivores, canopy frugivores and nectarivores). The local coexistence of these species is possible thanks to space, food and/or time partitioning. Space partitioning is consistent with the hypothesis that smaller bats with a more manoeuvrable flight tend to occupy more cluttered space less attractive to their competitors and have smaller home range. We observed a time partitioning that is likely to reduce competition among some frugivorous bat species by reducing direct interference during foraging. Besides an interest for the field community ecology, this study of a community living in a primary forest can be used as a reference for non disturbed habitat for conservation purposes. |
| Address |
Dept Ecol & Gestion Biodivers, UMR 5176, F-91800 Brunoy, France, Email: marguerite.delaval@wanadoo.fr |
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SOC NATL PROTECTION NATURE ACCLIMATATION FRANCE |
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0249-7395 |
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ISI:000230973300005 |
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no |
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EcoFoG @ eric.marcon @ |
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231 |
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Konig, A.O.; Ziegenhagen, B.; van Dam, B.C.; Csaikl, U.M.; Coart, E.; Degen, B.; Burg, K.; de Vries, S.M.G.; Petit, R.J. |
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Chloroplast DNA variation of oaks in western Central Europe and genetic consequences of human influences |
Type |
Journal Article |
| Year |
2002 |
Publication |
Forest Ecology and Management |
Abbreviated Journal |
For. Ecol. Manage. |
| Volume |
156 |
Issue |
1-3 |
Pages |
147-166 |
| Keywords |
Q. robur; Q. petraea; PCR-RFLPs; haplotypes; spatial genetic patterns; genetic differentiation; deforestation; seed transfer |
| Abstract |
Oak chloroplast DNA (cpDNA) variation was studied in a grid-based inventory in western Central Europe, including Belgium, The Netherlands, Luxembourg, Germany, the Czech Republic, and the northern parts of Upper and Lower Austria. A total of 2155 trees representing 426 populations of Quercus robur L. and Q. petraea (Matt.) Liebl. were screened for polymorphism in up to four PCR-amplified cpDNA fragments. Eleven haplotypes belonging to four lineages were detected; these lineages were formerly restricted to glacial refugia in the Iberian Peninsula, the Apennine Peninsula and the Balkan Peninsula. The haplotypes originating from the Apennines are particularly well represented in the study region, but there is also a significant contribution from the other refugia, which explain the high overall level of cpDNA diversity. The strong human impact in western Central Europe during the past centuries, which has resulted in the clearance of most forests, was followed by reforestation, sometimes involving seed transfers. Despite this strong human impact, broad geographic patterns of lineages and haplotypes could still be detected. To evaluate further the consequences of the former human activities on the present day oak cpDNA genetic structure, four regions where increasingly strong human impact was anticipated (ranging from hilly regions in southern Germany to roadsides plantations in The Netherlands) were selected. There, a comparison of the levels of intrapopulation cpDNA diversity and spatial structuring was made. Over the whole area, within stand diversity was significantly higher in Q. robur than in Q. petraea (h(S) = 0.24 vs. 0.16). Since total diversity is identical for both species, this results in a significantly lower level of fixation for Q. robur than for Q. petraea (G(ST) = 0.68 vs. 0.79). The analyses also reveal a decrease of fixation with increasing human impact on oak populations. The Dutch roadside plantations (Q. robur) exhibit a very low level of fixation (G(ST) = 0.28) as compared to Q. petraea in southern Germany (G(ST) = 0.91). The significance of the spatial genetic structure was tested using geostatistical methods. For the complete data set, a strong spatial genetic structure is confirmed, with higher than average genetic similarities between populations distant from up to 270 km, whereas there is no spatial structure in the roadside plantations in The Netherlands or in the northern German lowlands. These results should help to differentiate introduced from autochthonous populations, and provide a framework for the identification of the geographic origin of seed lots. (C) 2002 Elsevier Science B.V. All rights reserved. |
| Address |
Inst FOrstgenet & Forstpflanzenzuchtung, BFH, D-22927 Grosshansdorf, Germany |
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ELSEVIER SCIENCE BV |
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0378-1127 |
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ISI:000174149400010 |
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EcoFoG @ eric.marcon @ |
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276 |
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Rodrigues, A.M.S.; Stien, D.; Eparvier, V.; Espindola, L.S.; Beauchene, J.; Amusant, N.; Lemenager, N.; Baudasse, C.; Raguin, L. |
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The wood preservative potential of long-lasting Amazonian wood extracts |
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Journal Article |
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2012 |
Publication |
International Biodeterioration and Biodegradation |
Abbreviated Journal |
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75 |
Issue |
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Pages |
146-149 |
| Keywords |
Durable wood extracts; Handroanthus serratifolius; Rotting fungi; Wood preservation |
| Abstract |
Investigations were carried out on the efficacy of extracts from seven Amazonian woods (Bagassa guianensis, Manilkara huberi, Sextonia rubra, Vouacapoua americana, Andira surinamensis, Handroanthus serratifolius, and Qualea rosea) with varying natural durability to reduce soft-rot degradation in a 6-wk soil-bed test. Six of the wood extracts had shown efficacy against soft-rot fungi. In particular, the preservation efficacies of B. guianensis, H. serratifolius, and S. rubra extracts were highly significant up to retention levels of 23, 25, and 12 kg m-3, respectively. Three extracts (A. surinamensis, H. serratifolius, and Q. rosea) were then tested against Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot), in an agar-block test. H. serratifolius wood extract was very efficient at protecting P. sylvestris samples at 5.1 kg m-3 against the brown rot. This extract could be used as a basis for new wood protectant formulations. © 2012 Elsevier Ltd. |
| Address |
Laboratoire de Préservation, CIRAD, 73 rue JF Breton, Montpellier 34398, TA B 40-16, cedex 5, France |
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Export Date: 15 January 2013; Source: Scopus |
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EcoFoG @ webmaster @ |
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457 |
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Hmimina, G.; Dufrêne, E.; Pontailler, J.-Y.; Delpierre, N.; Aubinet, M.; Caquet, B.; de Grandcourt, A.; Burban, B.; Flechard, C.; Granier, A.; Gross, P.; Heinesch, B.; Longdoz, B.; Moureaux, C.; Ourcival, J.-M.; Rambal, S.; Saint André, L.; Soudani, K. |
| Title |
Evaluation of the potential of MODIS satellite data to predict vegetation phenology in different biomes: An investigation using ground-based NDVI measurements |
Type |
Journal Article |
| Year |
2013 |
Publication |
Remote Sensing of Environment |
Abbreviated Journal |
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132 |
Issue |
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Pages |
145-158 |
| Keywords |
Crops; Deciduous forests; Evergreen forests; Ground-based NDVI; Modis; Phenology |
| Abstract |
Vegetation phenology is the study of the timing of seasonal events that are considered to be the result of adaptive responses to climate variations on short and long time scales. In the field of remote sensing of vegetation phenology, phenological metrics are derived from time series of optical data. For that purpose, considerable effort has been specifically focused on developing noise reduction and cloud-contaminated data removal techniques to improve the quality of remotely-sensed time series. Comparative studies between time series composed of satellite data acquired under clear and cloudy conditions and from radiometric data obtained with high accuracy from ground-based measurements constitute a direct and effective way to assess the operational use and limitations of remote sensing for predicting the main plant phenological events. In the present paper, we sought to explicitly evaluate the potential use of MODerate resolution Imaging Spectroradiometer (MODIS) remote sensing data for monitoring the seasonal dynamics of different types of vegetation cover that are representative of the major terrestrial biomes, including temperate deciduous forests, evergreen forests, African savannah, and crops. After cloud screening and filtering, we compared the temporal patterns and phenological metrics derived from in situ NDVI time series and from MODIS daily and 16-composite products. We also evaluated the effects of residual noise and the influence of data gaps in MODIS NDVI time series on the identification of the most relevant metrics for vegetation phenology monitoring. The results show that the inflexion points of a model fitted to a MODIS NDVI time series allow accurate estimates of the onset of greenness in the spring and the onset of yellowing in the autumn in deciduous forests (RMSE ≤ one week). Phenological metrics identical to those provided with the MODIS Global Vegetation Phenology product (MDC12Q2) are less robust to data gaps, and they can be subject to large biases of approximately two weeks or more during the autumn phenological transitions. In the evergreen forests, in situ NDVI time series describe the phenology with high fidelity despite small temporal changes in the canopy foliage. However, MODIS is unable to provide consistent phenological patterns. In crops and savannah, MODIS NDVI time series reproduce the general temporal patterns of phenology, but significant discrepancies appear between MODIS and ground-based NDVI time series during very localized periods of time depending on the weather conditions and spatial heterogeneity within the MODIS pixel. In the rainforest, the temporal pattern exhibited by a MODIS 16-day composite NDVI time series is more likely due to a pattern of noise in the NDVI data structure according to both rainy and dry seasons rather than to phenological changes. More investigations are needed, but in all cases, this result leads us to conclude that MODIS time series in tropical rainforests should be interpreted with great caution. © 2013 Elsevier Inc. |
| Address |
INRA, Unité Biogéochimie des Ecosystèmes Forestiers, Champenoux, France |
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| Notes |
Export Date: 21 February 2013; Source: Scopus |
Approved |
no |
| Call Number |
EcoFoG @ webmaster @ |
Serial |
467 |
| Permanent link to this record |
