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Author Lebrini, M.; Robert, F.; Vezin, H.; Roos, C. openurl 
  Title (up) Electrochemical and quantum chemical studies of some indole derivatives as corrosion inhibitors for C38 steel in molar hydrochloric acid Type Journal Article
  Year 2010 Publication Corrosion Science Abbreviated Journal Corrosion Sci.  
  Volume 52 Issue 10 Pages 3367-3376  
  Keywords Steel; EIS; Raman spectroscopy; Polarization; Acid inhibition  
  Abstract A comparative study of 9H-pyrido[3,4-b]indole (norharmane) and 1-methyl-9H-pyrido[3,4-b]indole (harmane) as inhibitors for C38 steel corrosion in 1 M HCl solution at 25 degrees C was carried out. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of different concentrations of these inhibitors. The OCP as a function of time were also established. Cathodic and anodic polarization curves show that norharmane and harmane are a mixed-type inhibitors. Adsorption of indole derivatives on the C38 steel surface, in 1 M HCl solution, follows the Langmuir adsorption isotherm model. The Delta G degrees(ads) values were calculated and discussed. The potential of zero charge (PZC) of the C38 steel in inhibited solution was studied by the EIS method, and a mechanism for the adsorption process was proposed. Raman spectroscopy confirmed that indole molecules strongly adsorbed onto the steel surface. The electronic properties of indole derivates, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR). (C) 2010 Elsevier Ltd. All rights reserved.  
  Address [Robert, F.; Roos, C.] UAG UMR ECOFOG, Lab Mat & Mol Milieu Amazonien, Cayenne 97337, French Guiana, Email: christophe.roos@guyane.univ-ag.fr  
  Corporate Author Thesis  
  Publisher PERGAMON-ELSEVIER SCIENCE LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0010-938X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000281315500026 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 44  
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Author Lebrini, M.; Roos, C.; Vezin, H.; Robert, F. pdf  url
openurl 
  Title (up) Electrochemical and theoretical studies of adsorption of some indole derivates at C38 Steel/Sulfuric acid interface as corrosion inhibitors Type Journal Article
  Year 2011 Publication International Journal of Electrochemical Science Abbreviated Journal Int.J.Electrochem.Sci.  
  Volume 6 Issue 9 Pages 3844-3857  
  Keywords Acidic media; Adsorption; C38 steel; Corrosion inhibitors; Theoretical calculations  
  Abstract The inhibitive action of 9H-pyrido[3,4-b]indole (norharmane) and 1-Methyl-9H-pyrido[3,4-b]indole (harmane) on corrosion of C38 steel in 0.5 M H2SO4 solution was investigated through electrochemical techniques. The experimental results obtained revealed that these compounds inhibited the steel corrosion in acid solution for all concentrations studied. Polarization measurements indicate that the examined compounds act as a mixed inhibitor and its inhibition efficiency increases with inhibitor concentration. Data obtained from ac impedance technique show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE), has been used. The adsorption of used compounds on the steel surface obeys Langmuir's isotherm. The ΔG°ads values were calculated and discussed for both inhibitors. Significant correlations are obtained between inhibition efficiency and quantum chemical parameters using quantitative structure-activity relationship (QSAR) method. © 2011 by ESG.  
  Address Laboratoire de Chimie Organique et Macromoléculaire, UMR-CNRS 8009, USTL BâtC4, F-59655 Villeneuve d'Ascq Cedex, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 14523981 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2011; Source: Scopus; Language of Original Document: English; Correspondence Address: Robert, F.; Laboratoire Matériaux et Molécules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana; email: florent.robert@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 347  
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Author Ntienoue, J.K.; Reguer, A.; Robert, F.; Nait-Rabah, O.; Roos, C. pdf  url
openurl 
  Title (up) Electrochemical behaviour of a super austenitic stainless steel in amazonian aqueous environment Type Journal Article
  Year 2013 Publication International Journal of Electrochemical Science Abbreviated Journal Int.J.Electrochem.Sci.  
  Volume 8 Issue 4 Pages 4761-4775  
  Keywords Cyclic voltammetry; Eis; Esem; Passive films; Stainless steel  
  Abstract The electrochemical behaviour of 254 SMO super austenitic stainless steel in natural seawater collected from river mouth of French Guiana was investigated. A comparative study of samples immersed during 22 days in this environment was made including influences of scraped biofilm introduced in experiments and of stirring. Electrochemical measurements – open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and linear polarisation (LP) – are used to characterize the metal/medium interface included biofilms adhesion. The EDX analysis (EDAX system) shows that the chemical composition of adhered biofilm consists mostly of iron, oxygen, silicon and aluminium and seem preferentially bind on metal defects. © 2013 by ESG.  
  Address Laboratoire Matériaux et Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana  
  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 14523981 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 24 April 2013; Source: Scopus; Language of Original Document: English; Correspondence Address: Roos, C.; Laboratoire Matériaux et Molécules en Milieu Amazonien, Université des Antilles et de la Guyane, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana; email: christophe.roos@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 483  
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Author Touchard, A.; Dauvois, M.; Arguel, M.-J.; Petitclerc, F.; Leblanc, M.; Dejean, A.; Orivel, J.; Nicholson, G.M.; Escoubas, P. url  openurl
  Title (up) Elucidation of the unexplored biodiversity of ant venom peptidomes via MALDI-TOF mass spectrometry and its application for chemotaxonomy Type Journal Article
  Year 2014 Publication Journal of Proteomics Abbreviated Journal J. Proteomics  
  Volume 105 Issue Pages 217-231  
  Keywords Ant venom; Chemotaxonomy; Maldi-Tof Ms; Peptide; Peptidome; Ponerinae; ant venom; cytochrome c oxidase; ant; article; biodiversity; chemotaxonomy; correlational study; DNA sequence; French Guiana; Hymenoptera; matrix assisted laser desorption ionization time of flight mass spectrometry; mitochondrial gene; nonhuman; Odontomachus biumbonatus; Odontomachus haematodus; Odontomachus hastatus; Odontomachus mayi; Odontomachus scalptus; Pachcondyla apicalis; Pachcondyla arhuaca; Pachcondyla commutata; Pachcondyla constricta; Pachcondyla crassinola; Pachcondyla goeldii; Pachcondyla inversa; Pachcondyla marginata; Pachcondyla procidua; Pachcondyla stigma; Pachcondyla verenae; Pachcondyla villosa; peptidomics; phylogeny; priority journal; Animalia; Formicidae; Hymenoptera; Odontomachus; Pachycondyla; Pachycondyla apicalis; Pachycondyla stigma; Ponerinae  
  Abstract The rise of integrative taxonomy, a multi-criteria approach used in characterizing species, fosters the development of new tools facilitating species delimitation. Mass spectrometric (MS) analysis of venom peptides from venomous animals has previously been demonstrated to be a valid method for identifying species. Here we aimed to develop a rapid chemotaxonomic tool for identifying ants based on venom peptide mass fingerprinting. The study focused on the biodiversity of ponerine ants (Hymenoptera: Formicidae: Ponerinae) in French Guiana. Initial experiments optimized the use of automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to determine variations in the mass profiles of ant venoms using several MALDI matrices and additives. Data were then analyzed via a hierarchical cluster analysis to classify the venoms of 17 ant species. In addition, phylogenetic relationships were assessed and were highly correlated with methods using DNA sequencing of the mitochondrial gene cytochrome c oxidase subunit 1. By combining a molecular genetics approach with this chemotaxonomic approach, we were able to improve the accuracy of the taxonomic findings to reveal cryptic ant species within species complexes. This chemotaxonomic tool can therefore contribute to more rapid species identification and more accurate taxonomies. Biological significance: This is the first extensive study concerning the peptide analysis of the venom of both Pachycondyla and Odontomachus ants. We studied the venoms of 17 ant species from French Guiana that permitted us to fine-tune the venom analysis of ponerine ants via MALDI-TOF mass spectrometry. We explored the peptidomes of crude ant venom and demonstrated that venom peptides can be used in the identification of ant species. In addition, the application of this novel chemotaxonomic method combined with a parallel genetic approach using COI sequencing permitted us to reveal the presence of cryptic ants within both the Pachycondyla apicalis and Pachycondyla stigma species complexes. This adds a new dimension to the search for means of exploiting the enormous biodiversity of venomous ants as a source for novel therapeutic drugs or biopesticides. This article is part of a Special Issue entitled: Proteomics of non-model organisms. © 2014 Elsevier B.V.  
  Address Neurotoxin Research Group, School of Medical and Molecular Biosciences, University of Technology, Sydney, NSW, Australia  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 18767737 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Cited By (since 1996):1; Export Date: 30 July 2014; Correspondence Address: Touchard, A.; UMR-EcoFoG, Campus Agronomique, BP 316, 97379 Kourou Cedex, France; email: axel.touchard@ecofog.gf; Chemicals/CAS: cytochrome c oxidase, 72841-18-0, 9001-16-5 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 555  
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Author Urbina, I.; Grau, O.; Sardans, J.; Ninot, J.M.; Peñuelas, J. doi  openurl
  Title (up) Encroachment of shrubs into subalpine grasslands in the Pyrenees changes the plant-soil stoichiometry spectrum Type Journal Article
  Year 2020 Publication Plant and Soil Abbreviated Journal Plant Soil  
  Volume 448 Issue 1-2 Pages 37-53  
  Keywords Nutrient stocks; Plant strategy; Plant-soil stoichiometry; Shrub encroachment; Subalpine grassland succession; aboveground biomass; biogeochemical cycle; carbon sequestration; ectomycorrhiza; fungus; grass; nitrogen; nutrient uptake; shrub; soil-vegetation interaction; stoichiometry; subalpine environment; succession; Europe; Pyrenees; Fungi  
  Abstract Aims: Shrub encroachment has been reported over a large proportion of the subalpine grasslands across Europe and is expected to have an important impact on the biogeochemical cycle of these ecosystems. We investigated the stoichiometric changes in the plant-soil system along the succession (e.g. increase in encroachment from unencroached grassland to mature shrubland) at two contrasting sites in the Pyrenees. Methods: We analyzed the chemical composition (C, N,15N, P, K, Ca, Mg and Fe) in the soil and in the aboveground plant compartments (leaves, leaf-litter and stems) of the main herbaceous species and shrubs at three contrasting stages of the succession: unencroached grassland, young shrubland and mature shrubland. Results: The plant-soil stoichiometry spectrum differed between the successional stages. Shrub encroachment generally increased the concentration of C and Ca and the C:N ratio and often reduced to concentrations of N, P and K in the leaves and leaf-litter, while several soil nutrient concentrations (N, P, K Ca and Mg) decreased. The stocks of C, N, P, Ca, and Mg in the total aboveground biomass increased with encroachment. Conclusions: Shrub encroachment favored the dominance of long-lived species with low concentrations of N and P in the plant-soil compartments, high C:nutrient ratios in the aboveground biomass and increase the uptake of N through ericoid or ectomycorrhizal fungi. We highlight the role of shrubs in the sequestration of C and nutrients through the allocation to the aboveground biomass. The changes in plant-soil elemental composition and stocks suggest a slowdown of the biogeochemical cycles in the subalpine mountain areas where shrub encroachment occurred. © 2020, Springer Nature Switzerland AG.  
  Address Biodiversity Research Institute (IRBio) and Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona, Catalonia, Spain  
  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 0032079x (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 983  
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Author Seymour, R.S.; White, C.R.; Gibernau, M. openurl 
  Title (up) Endothermy of dynastine scarab beetles (Cyclocephala colasi) associated with pollination biology of a thermogenic arum lily (Philodendron solimoesense) Type Journal Article
  Year 2009 Publication Journal of Experimental Biology Abbreviated Journal J. Exp. Biol.  
  Volume 212 Issue 18 Pages 2960-2968  
  Keywords beetle; endothermy; pollination biology; Cyclocephala; Philodendron  
  Abstract Cyclocephala colasi beetles are facultative endotherms that spend most of their adult lives inside the inflorescences of Philodendron solimoesense, where ambient temperature (T-a) averages about 28 degrees C due to floral thermogenesis. Measurements of respiration within a range of T-a showed that active beetles became spontaneously endothermic at T-a below 28 degrees C but were rarely endothermic above it. There was no evidence of endothermy within the inflorescences, indicating that activities in the floral chamber can occur without the high energy expense of endothermy. Bouts of endothermy occurred at lower T-a in respirometer chambers mainly in the evening, when the insects normally fly from one inflorescence to another, and during the night, when they normally eat and mate within the inflorescence. Patterns of endothermy in individual episodes were studied in non-flying beetles with respirometry and infrared thermal imaging. Heat was generated in the thorax by oscillatory waves of respiration that were coupled with thoracic temperature (T-th) increases. Stationary beetles could regulate T-th at about 33 degrees C independently of T-a between 16 and 29 degrees C. At T-a=20 degrees C, this represents a 116-fold increase in metabolic rate over resting, ectothermic values. Endothermy was clearly a requirement for flight, and beetles departing inflorescences warmed to about 30 degrees C before take-off. During flight, T-th was dependent on T-a, decreasing from 37 to 28 degrees C at T-a of 37 to 20 degrees C, respectively. The lowest T-a at which flight could occur was about 20 degrees C. Thermal conductance of stationary, endothermic beetles increased at higher metabolic rates, probably because of increased ventilatory heat loss.  
  Address [Seymour, Roger S.] Univ Adelaide, Sch Earth & Environm Sci, Adelaide, SA 5005, Australia, Email: roger.seymour@adelaide.edu.au  
  Corporate Author Thesis  
  Publisher COMPANY OF BIOLOGISTS LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000269383500014 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 198  
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Author Salvin, P.; Ondel, O.; Roos, C.; Robert, F. doi  openurl
  Title (up) Energy harvest with mangrove benthic microbial fuel cells Type Journal Article
  Year 2015 Publication International Journal of Energy Research Abbreviated Journal Int J Energy Res  
  Volume 39 Issue 4 Pages 543-556  
  Keywords Balancing circuit; Benthic microbial fuel cell; Efficiency; Energy harvesting  
  Abstract Benthic microbial fuel cells (BMFCs) are continuous electricity generators using electroactive microorganisms and organic matter from aquatic environment, respectively, as catalysts and substrate. In this paper, first a low-cost PVC-made structure is constructed to harvest electricity from mangrove environment located in French Guiana. An in situ BMFC has given power density of 30mW/m2 of the anodic surface area. This performance has been confirmed by experience in laboratory where inter-electrode distance and electrode surface area appeared to be power increasing factors. However, the output power of one BMFC is not used to supply real devices such as autonomous sensors. Second, to meet this expectation, in parallel and in series associations were considered. These associations were made in order to increase the output voltage and consequently the power, to reach levels that can supply small sensors (about 3V). Finally, to improve the performance of the series association and to avoid the voltage reversal phenomenon, a voltage balancing circuit was simulated and added to the series connections. With balancing method, the cell voltage of BMFCs can be equalized, and the performances can be improved. This allows an optimal energy harvesting and a better global efficiency of the set.  
  Address Université de Lyon, F-69622, Lyon, France, Université Lyon 1, Villeurbanne; CNRS, UMR 5005, Laboratoire Ampère, 43, Boulevard du 11 Novembre 1918Villeurbanne, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 17 March 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 586  
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Author Chevalier, M.; Robert, F.; Amusant, N.; Traisnel, M.; Roos, C.; Lebrini, M. url  openurl
  Title (up) Enhanced corrosion resistance of mild steel in 1 M hydrochloric acid solution by alkaloids extract from Aniba rosaeodora plant: Electrochemical, phytochemical and XPS studies Type Journal Article
  Year 2014 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta  
  Volume 131 Issue Pages 96-105  
  Keywords Acidic media; Adsorption-XPS; Aniba rosaeodora extract; Anibine; C38 steel; Corrosion inhibitor  
  Abstract The present report continues to focus on the broadening application of plant extracts for metallic corrosion control and reports on the inhibiting effect of the Aniba rosaeodora alkaloidic extract on the corrosion of C38 steel in 1 M hydrochloric acid. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of inhibitor. Studies on the phytochemical constituents were established to determine the active(s) molecule(s). XPS was also carried out to establish the mechanism of corrosion inhibition of the active molecule of C38 steel in acid solution. The inhibitor extract acted as an efficient corrosion inhibitor in 1 M HCl. The experimental data obtained from EIS method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPEα, Q) has been used. Graphical methods are illustrated by synthetic data to determine the parameter of CPE (α, Q). Polarization studies showed that the Aniba rosaeodora alkaloidic extract was a mixed-type inhibitor and its inhibition efficiency increased with the inhibitor concentration. Studies on the phytochemical constituents of the total alkaloids extract shows that it contains the anibine as the major alkaloid. The results obtained from the electrochemical study have clearly showed that the inhibition efficiency of the total extract was due to the presence of anibine. The XPS studies showed the formation of inhibitor layer containing the Aniba rosaeodora alkaloidic extract and the anibine molecules. © 2014 Elsevier Ltd. All rights reserved.  
  Address Unité Matériaux et Transformations CNRS UMR 8207, Université Lille 1, École Nationale Supérieure de Chimie de Lille, Avenue Dimitri Mendeleïev-Bât. C7a BP 90108, 59652 Villeneuve d'Ascq, France  
  Corporate Author Thesis  
  Publisher Elsevier Ltd Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00134686 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 10 June 2014; Coden: Elcaa; Correspondence Address: Lebrini, M.; Laboratoire Matériaux et Molécules en Milieux Amazonien, UAG-UMR ECOFOG Campus Troubiran, Route de Baduel, 97337 Cayenne, French Guiana; email: mounim.lebrini@guyane.univ-ag.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 545  
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Author Marcon, E.; Herault, B. pdf  url
openurl 
  Title (up) entropart: An R package to measure and partition diversity Type Journal Article
  Year 2015 Publication Journal of Statistical Software Abbreviated Journal Journal of Statistical Software  
  Volume 67 Issue 8 Pages 1-26  
  Keywords Biodiversity; Entropy; Partitioning  
  Abstract entropart is a package for R designed to estimate diversity based on HCDT entropy or similarity-based entropy. It allows calculating species-neutral, phylogenetic and functional entropy and diversity, partitioning them and correcting them for estimation bias. © 2015, American Statistical Association. All rights reserved.  
  Address Cirad, Campus agronomique, BP 316, Kourou, French Guiana  
  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 ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 22 October 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 633  
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Author Marcon, E. url  doi
openurl 
  Title (up) Entropy as a common measure of biodiversity and the spatial structure of economic activity Type Journal Article
  Year 2019 Publication Revue Economique Abbreviated Journal Rev. Econ.  
  Volume 70 Issue 3 Pages 305-326  
  Keywords Diversity; Economic geography; Spatial concentration; Specialization  
  Abstract Measures of spatial concentration and specialization in economics are similar to those of biodiversity and ubiquity of species in ecology. Entropy is the fundamental tool that originated in statistical physics and information theory. The definition of number equivalents or effective numbers, that is the number of types in an ideal, simplified distribution, is introduced along with the partitioning of the joint diversity of a bi-dimensional distribution into absolute and relative concentration or specialization and replication. The whole framework is theoretically robust and allows measuring the spatial structure of a discrete space.  
  Address AgroParisTech, UMR Écologie des forêts de Guyane, CNRS, Cirad, INRA, Université des Antilles, Université de Guyane, Campus Agronomique, BP 701, Kourou, 97310, French Guiana  
  Corporate Author Thesis  
  Publisher Presses de Sciences Po Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00352764 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 912  
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