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During their development, insects can suck plant structures like seeds and fruits being the preferred structures. The study aims to monitor the eating habits of these insects are relevant mainly in terms of food preference and development. The objective of this work was to analyze the feeding preference of Euschistus heros (brown stink bug) fed with 5 diets. The different diets studied resulted in insects in adult, with significant differences in the length of the nymph period, differences in the weights of males and females and variation in survival during the experiment.

Taphonomic analysis is a useful tool to assess the intensity of alteration of skeletal remains and to help characterize depositional conditions as well as completeness and resolution of fossil assemblages. We herein introduce TAPHOGRAPH, an Excel spreadsheet script (a R code is also available), for the production of taphonomic diagrams to characterize the taphonomy of skeletal remains. The graphical representation depicts four taphonomic factors (fragmentation, abrasion, bioerosion, and encrustation) as a cumulative curve that allows visualization and comparison of the degree and variability of taphonomic alteration for different hard part types from one or more samples in a single diagram. The TAPHOGRAPH methodology is highly flexible, and can be used to assess the relative influence of mechanical versus biological (versus chemical) taphonomic alteration. The TAPHOGRAPH approach can guide inferences about hydraulic regimes, residence time at the seafloor, and intensity of different taphonomic processes.

International audience; This article presents the realization of a bandpass filter on a flexible biopolymer substrate with a suitable fabrication process. We used copper adhesive tape and laser structuring to fabricate the filter based on a quasi-lumped microstrip structure. The filter characteristics are a central frequency of 2.45 GHz, a bandwidth of 20%, and insertion loss of 1.2 dB. It is demonstrated that the filter's performance remains almost constant under different bending, folding, and rolling conditions. The results show that the proposed bio-sourced polymer is a good candidate for flexible green electronics and wearable applications.

International audience; Platform molecules were defined by the US Department of Energy, as bio-based or bio-derived chemicals whose constituting elements totally originated from biomass and could be used as building blocks for the production of commodity and refined chemicals. These chemicals can subsequently be converted into a number of high-value bio-based chemicals or materials. Today, there is a growing urge for the discovering of a cheaper and cleaner way for the environment to produce platform molecules from renewable substrate such as carbon. Succinic acid (SA) is considered as a key platform chemical since it is used as a precursor for other valuable chemicals and has aroused interest worldwide with its wide applications. This review aims at highlighting the currently available information about the mechanisms involved in the production of platform molecules, especially the SA production. In this review, the processing technologies used in the production of platform molecules are described, in addition to the information regarding the optimization of key parameters, the mechanisms of genetic engineering and finally the redox potential and purification processes which are known as alternative cost-competitive providers of fossil fuels.

International audience; In the current paper, we investigate a nonlocal hyperbolic problem with volume constraints. The main motivation of this work is to apply the nonlocal vector calculus, introduced and developed by DU et al. [3] to such problem. Moreover, based on some density arguments, some a priori estimates and using the Galerkin approach, we prove existence and uniqueness of a weak solution to the nonlocal wave equation. 1. Introduction. The study of nonlocal problems has gained great attention over the last two decades. Nonlocal models involve integral equations and fractional derivatives allowing nonlocal interactions, that is to say, the interaction may occur even when the closures of two domains have an empty intersection. Such models are effective in modeling material singularities and are widely considered in a variety of applications, including image analyses [6]-[10], phase transition [4][11], machine learning [12] and obstacle problem [5]... In a major advance in 2013, Du et al. [3] introduced nonlocal vector calculus as a nonlocal framework to understand and analyze nonlocal problems. It defines non-local fluxes , nonlocal analogues of the gradient, divergence, and curl operators, and presentes some basic nonlocal integral theorems that mimic the classical integral theorems of the vector calculus for differential operators, the authors have also provided connection between the nonlocal operators and their usual differential counterparts in a distributional sense then in a weak sense by introducing nonlocal weighted operators. The present paper was motivated by [2], where the authors threw light on the analogy between nonlocal and local diffusion problems with a convincing explanation of the usefulness, in the nonlocal case, of volume constraints which represent the nonlocal analogue of the boundary conditions of the classical theory. Our purpose

International audience; This paper presents a flexible and wearable (on-body) dual band antenna operating in two Industrial, Scientific and Medical (ISM) frequency bands. The central frequencies selected are equal to 2.45 GHz and 5.8 GHz. In order to make the antenna suitable for Wireless Body Area Network (WBAN) applications, it is fabricated on a flexible biopolymer called cellulose laurate (CL). The proposed antenna, that has been designed and optimized on ANSYS HFSS, is realized using a process based on copper adhesive tape and laser structuring. The characterization of the antenna in terms of reflection coefficient, gain and radiation patterns shows a good agreement with the simulation data. Compared to state-of-the-art antennas, the investigated solution demonstrates competitive results. The proposed antenna also features stable performance under bending conditions and the estimated specific absorption rate (SAR) is well below the limits defined by international standards. All these results suggest that the proposed antenna is very well suited for potential wearable applications and is a step towards fully green electronics.

A new graphical representation of the taphonomy of skeletal carbonates observed at the thin-section scale is proposed, demonstrating their utility in drawing information about the effects of early sea-floor processes on the post-mortem fate of fossil hard parts. The graphical representations consist of two-axis diagrams, which integrate the degree of fragmentation, abrasion, bioerosion, and encrustation as primary descriptors of the average state of fossil remains in a Miocene limestone section from southeastern North Island of New Zealand. Numerical values are expressed as percentages that represent the contribution of each factor to alteration (i.e., the four factors represent up to 25% each of the total alteration), the sum of values quantifying the amount of departure from pristine condition. Data are plotted in a cumulative form that reflects synergistic action of sea-floor processes towards hard parts destruction. One important virtue of this graphical representation is that the nature, degree, and variability of taphonomic alteration can be visualized and compared in a single diagram for several grain categories within a sample, and between samples. The proposed scheme is particularly flexible because more than four taphonomic categories can be integrated, independently from the number of alteration classes specific to each category, provided conversion of scores obtained in each taphonomic categories into percentages. Compiled results of such taphonomic analyses could be used in the future to identify specific depositional conditions, such as hydraulic regime, transportation, and residence time on the sea floor (a potential proxy to net accumulation rates).

Among other parameters, volcanic activity adjacent to shallow marine environments influences the development of ecosystems and their carbonate-producing communities. Volcaniclastic sediment influx in particular has potential to cause rapid and drastic environmental changes affecting biological systems in their composition and activity, and ultimately leading to changes to and breaks in carbonate sedimentation. Such sedimentary breaks that form in response to volcanic processes are rarely described in detail despite the common occurrence of carbonate platforms adjacent to active volcanoes both in the recent and past geological record. The Island of St. Bartholomew (St. Barths), French West Indies, exposes sections of middle Eocene limestones intercalated with thick volcaniclastic deposits and lavas. Theses carbonates provide an example of a low-latitude tropical platform where non-framework building biota were important, if not dominant, sediment contributors. The carbonate system records the repeated collapse and renewal of carbonate production, as a result of episodic volcaniclastic material input. The discontinuous nature of the carbonate sedimentation is reflected in contrasted depositional systems across sedimentary surfaces and gradational contacts. The studied Eocene deposits provide a sedimentary record of how volcanic events impacted warm-water carbonate factories, both in their disturbance, demise and recovery.

International audience; Yeast strains were isolated from sugar cane molasses (S1), dates (S2) and figs (S3) and the ethanol production was evaluated in batch condition. A comparison was made with the yeast Saccharomyces cerevisiae. The strains showed tolerant characteristics to stressful conditions like salinity and ethanol. The isolated strains produced ethanol; at 20 h of fermentation ethanol yields were 0.38-0.39 g.g-1 , and the productivities were almost 0.58 g.L-1. S. cerevisiae and S1 tolerated up to 14% (v/v) of ethanol; while interestingly the isolates S2 and S3 were highly tolerant, up to 20% (v/v) ethanol. Thus, S2 and S3 could serve as potential strains for ethanol fermentation, with 0.27 and 0.29 g.g-1 yield of ethanol in the presence of 1.37 mol.L-1 NaCl. These values were higher than the value obtained using the yeast of reference and S1 (0.16 g.g-1). Co-cultures of S2 and S3 enhanced the ethanol production, increasing the yield of ethanol by 12.5% compared with the single culture. The strains were identified as species S.cerevisiae, and S2 and S3 were very similar. For an application in the valorization of biomass such as green macro-algae, some assays were done on a synthetic model medium of hydrolysate of macro-algae and the strains S2 and S3 demonstrated excellent fermentative performances.

International audience; The objective of this study was to improve the mineralization of metronidazole, a recalcitrant antibiotic by the development of a new combined process coupling electro-Fenton and a biological process. For biotreatment, various strategies were considered bioaugmentation, bioacclimatation and biostimulation alone or combined. So, the novelty of this strategy is to combine advanced oxidation process with advanced biological process. The conventional biotreatment with activated sludge after 120 h of culture, led to 58.1% mineralization, whereas the pure isolated strains, from activated sludge culture in the presence of metronidazole by-products, identified as Pseudomonas putida (strain A) and Achromobacter sp. (strain B), led to 37.2% and 40.1% respectively. After original acclimation of the isolated strains to electrolysis by-products, the mineralization levels reached 75.6% and 72.9% for strains A and B respectively after 120 h of culture. The results showed that the mineralization of metronidazole by-products was the most important in the case of the combination of autochthonous bioaugmentation and biostimulation, with 96.1% after 120 h of treatment. By coupling the two processes, the global treatment reached therefore a mineralization yield of 97% with a reduction in processing time of 16 days compared to previous conventional biological treatment.

Despite the advances made over the last decade, infections caused by multi-drug resistant bacterial strains are increasingly important societal issues that need to be addressed. New approaches have already been developed in order to overcome this problem. Photodynamic antimicrobial chemotherapy (PACT) could provide an alternative to fight infectious bacteria. This approach has already inspired the development of innovative materials. Interesting results have been obtained against Gram-positive bacteria, but it also appeared that Gram-negative strains, especially Pseudomonas aeruginosa, were less sensitive to PACT. Enhanced efficacy against Gram-negative bacteria had been previously obtained with photosensitizers bound to antimicrobial peptides. In this work, we designed a photobactericidal organic material, CNCsc6-PMB, consisting of cellulose nanocrystals to which the photosensitizer chlorin-e6 and the antimicrobial polypeptide polymyxin B (PMB) were covalently attached. These modified nanocrystals were characterized by IR spectroscopy, zeta potential measurements and elemental analyses, after which antibacterial assays were carried out. Following light irradiation, CNCsc6-PMB demonstrated efficiency against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis) by inhibition of bacterial growth. An amplifying effect of chlorin-e6 has been highlighted against these Gram-negative strains, based on membrane weakening and a potential docking effect from the polymyxin moiety. Such results confirmed the importance of using an antimicrobial peptide in order to broaden the spectrum of PACT.

The purpose of this study is to obtain ionically cross-linked gellan particles containing immobilized yeast cells. The zinc acetate was chosen as a cross-linking agent due to its beneficial role in the growth and nutrition of yeast cells and also due to the advantages of its use in fermentation processes. The physicochemical and morphological properties as well as the fermentative activity of the obtained particles were studied. The zinc acetate concentration has an influence on particles stability in water, on the mechanical stability and also on the swelling degree. The morphology of the obtained particles was analyzed by SEM and proves that the yeast cells are immobilized in large numbers in the polymeric matrix. The cell viability is maintained at high values after several fermentation cycles. These obtained micro-bioreactors were tested in terms of fermentative activity and the fermentation process was optimized by studying the influence of several factors. The gellan gum particles can be easily recovered by filtration and they can be reused in repeated fermentation cycles. The results obtained in the presence of these cross-linked particles are comparable to those achieved in the free yeast fermentation.

International audience; The photocatalytic removal of Flumequine (antibiotic) using a luminous textile which served as a support for the TiO2 and a light transmitter through optical fibers was examined in this study. Two configurations of luminous textile were investigated (Mono-Face and Double-Face) in terms of compounds degradation and mineralization. Photocatalytic performances of Double-Face configuration were found to be better than the one obtained with Mono-Face. Furthermore, to describe the kinetics of the reaction, the Langmuir-Hinshelwood model was successfully applied and both reaction kinetic and adsorption/desorption equilibrium constants were determined. Double-Face configuration also showed better performances compared to the conventional process in the different water matrices tested (ultrapure water, synthetic solution simulating seawater and synthetic hospital wastewater). This configuration was tested for cetirizine (antihistamine) degradation as well, with a satisfying result obtained. Moreover, this technology showed good stability and reusability. On the other hand, the larger size of Double-Face retained its performance at pilot-scale. Finally, the irradiation analyzes showed a good light distribution homogeneity on the textile surface at both laboratory-scale and pilot-scale.

Graphical abstract Scheme 1. Representation of enzymatic transformation of carbohydrates into glycolipids and the formation of biosurfactants in heterogenous medium., Highlights • This review summarizes most recent works on biocatalytic synthesis of glycolipids. • Main parameters affecting enzymatic synthesis of amphiphilic carbohydrates. • The outlined information embraces the development of green biosynthetic techniques., Glycolipids, carbohydrate fatty esters or sugar esters are amphiphilic molecules containing hydrophilic groups bonded to hydrophobic parent structures. Recently, glycolipids have shown their antimicrobial and antitumor capacities. Their surface activity properties have applications in the food, pharmaceutical and cosmetic industries. Sugar esters’ building blocks can be obtained from natural resources and/or be transformed by biochemical pathways for uses as surfactants. Biosurfactants are non-ionic, nontoxic, biodegradable, tasteless, and odourless. The biocatalysis of these molecules involves sustainable, green, and safer methods. The advantages of producing biosurfactants from enzymatic catalysis are the energy economy, high selectivity, production of natural products, reduction of the use of fossil-based solvents and chloride compounds. This review presents the most recent studies concerning the evaluation of the impact of the main parameters and their levels influencing the enzymatic synthesis of glycolipids. Various enzyme catalysed synthetic methods were described. The parameters studied were temperature, reaction time, solvent system, type of biocatalyst, substrates molar ratio proportion and the nature of substrates. This review discusses the influence of different biocatalysts in the conversions of glycolipids; The reactivity from mono to polysaccharides and their interaction with fatty acids of different carbon chain lengths in the presence of specific enzymes; The effect of the solvent polarity, the use of multiple solvents, ionic liquids, supercritical CO2, and solvent-free media in sugar ester conversions; And the optimization of temperature and reaction time in different enzymatic systems.

International audience; Polylactic acid (PLA) is a bio-based and biodegradable polymer currently used in a wide range of packaging, medical, and industrial applications. PLA is also envisaged for the development of sustainable products for general public, including electronic devices. For these applications, the knowledge of the dielectric properties is required, in particular for high frequency electronics. In this letter, coplanar waveguides are realized on a PLA substrate in order to characterize its complex permittivity from 0.5 to 67 GHz. To avoid putting the PLA in contact with strong chemicals or solvents, a line transfer technique combined with photolithography process has been developed to realize the test structure. The propagation constant is calculated by de-embedding techniques using S-parameter measurements. Finally, finite element method analysis is used to determine the real permittivity (epsilon(r)) and loss tangent (tan delta) of the PLA substrate.

cited By 0; International audience; In this work, the dielectric properties of a biosourced polymer are investigated. To that end, coplanar transmission lines were fabricated on a 600 μm thick cellulose palmitate substrate by using a transfer technique and photolithography. Then, the S-parameters of the transmission lines were measured in a broad microwave frequency band spanning from 0,5 to 67 GHz. Finally, the propagation constant was determined and the complex effective permittivity was extracted.

International audience; This study deals with photocatalytic application for indoor air pollution remediation. Two target compounds were selected: Butane-2,3-dione (C4H6O2) and Heptan-2-one (C7H14O). Escherichia coli (E. coli) were used as bacteria strain. Photocatalytic removal of VOCs alone, E. coli alone and their mixture (VOCs/E. coli) were evaluated, at pilot scale. Indeed, a series of experiments were carried out in a continuous planar reactor using a novel photocatalyst/TiO2 technology with metal wires e.g. Copper (Cu)/Silver (Ag)-woven in optical fiber. Effects of experimental conditions such as flow rate (2–12 m3.h−1), VOCs inlet concentration (5–20 mg.m−3) and humidity levels (5–70%) on removal efficiency were investigated to properly appraise the oxidation performance in real conditions. All textile fiber photo-catalysts (TiO2, TiO2-Cu and TiO2-Ag) showed good photocatalytic activities towards C4H6O2/C7H14O removal. As for simultaneous application with VOCs and E. coli: (i) in terms of VOCs removal efficiency, the same trend of performance was observed compared to VOCs experiments alone: 63% of removal efficiency by TiO2 alone, 46% by TiO2-Ag and 52% by TiO2-Cu, (ii) in terms of E. coli inactivation, only experiments with TiO2-Cu and TiO2-Ag revealed a good performance

A new decapod brachyuran, Maurocarpilius binodosus n. gen., n. sp. (Carpiliidae Ortmann, 1893), from the Ait Ouarhitane Formation (early Eocene, Ypresian) of Tamalout (Ouarzazate, Morocco) is described herein. This is the first record of a decapod from the Eocene of Morocco formally reported, and represents an addition to the large record of carpiliids from the Paleogene of the western margin of the Tethys. The new taxon is characterized as follows: a strongly vaulted and smooth carapace, a front strongly downturned, anterolateral margins broadly convex with two small nodes, and concave posterolateral margins. Maurocarpilius binodosus n. gen., n. sp. presents clear morphological similarities with coeval taxa from the northern Iberian Peninsula and northern Italy, and the origins of those taxa and their possible phylogenetic relationships are discussed. Moreover, the paleobiogeography of the populations of carpiliids during the early Eocene in the western end of the Tethys is analyzed, and a possible connection between the Tethys Sea and the Bay of Biscay, that could have favored the faunal exchange between the North Atlantic and the Tethyan domains, is proposed.

International audience

Plesiadapidae are among the most successful mammal families of the Paleocene, but in North America they disappear abruptly around the Paleocene-Eocene boundary. In contrast, in Europe, they survive a few million years into the Eocene, although only as the genus Platychoerops. The latest Paleocene deposits of Petit-Pâtis (Paris Basin, France) have produced three new plesiadapid species, one of each genus known in Europe: Plesiadapis ploegi, sp. nov., Platychoerops boyeri, sp. nov., and Chiromyoides mauberti, sp. nov. Each of these new species is represented by the very characteristic upper incisor, thus ascertaining their concomitant presence and in particular the spatial and temporal coexistence of Plesiadapis and Platychoerops. Plesiadapis ploegi, sp. nov., is morphologically intermediate between Plesiadapis tricuspidens and Platychoerops russelli, with a tricuspid I1 typical of Plesiadapis and a semimolariform p4 closer to Platychoerops. Its relatively high morphological variability is illustrated. Platychoerops boyeri, sp. nov., has the simple derived I1 of all Platychoerops and a p4 slightly more molariform than that of Ples. ploegi. Chiromyoides mauberti, sp. nov., is closest to Chiromyoides campanicus, but it is smaller and has a particular I1 with multiple posterocones. The systematic position of ‘Platychoerops’ georgei is discussed; this taxon is considered a chimera, and its type I1 belongs to either Chiromyoides or Plesiadapis. Cladistic analysis highlights the paraphyly or polyphyly of all genera of Plesiadapidae. Finally, there is some indication of morphological convergences between European and North American plesiadapids, which may be the result of similar environmental changes on both continents just before the Paleocene-Eocene boundary. http://zoobank.org/urn:lsid:zoobank.org:pub:A73AEFC3-AA93-4EB6-8BD2-E3B15515C6FB SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: De Bast, E., C. Gagnaison, and T. Smith. 2018. Plesiadapid mammals from the latest Paleocene of France offer new insights on the evolution of Plesiadapis during the Paleocene-Eocene transition. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1460602.

International audience; In this study, the monitoring of reactive oxygen species and the regeneration of the ferrous ions catalyst were performed during electro-Fenton (EF) process to highlight the influence of operating parameters. The removal of metronidazole (MTZ) was implemented in an electrochemical mono-compartment batch reactor under various ranges of current densities, initial MTZ and ferrous ions concentrations, and pH values. It was found that under 0.07 mA cm−2, 0.1 mM of ferrous ions and pH = 3, the efficiency of 100 mg L−1 MTZ degradation and mineralization were 100% within 20 min and 40% within 135 min of electrolysis, respectively. The highest hydrogen peroxide and hydroxyl radical concentrations, 1.4 mM and 2.28 mM respectively, were obtained at 60 min electrolysis at 0.07 mA cm−2. Improvement of the biodegradability was reached from 60 min of electrolysis with a BOD5/COD ratio above 0.4, which was reinforced by a respirometric study, that supports the feasibility of coupling electro-Fenton and biological treatment for the metronidazole removal.

In a previous study we used asymmetric-flow field-flow fractionation to determine the polymer mass (Mw), gyration radius (Rw) and the polydispersity index of glutenin polymers (GPs) in wheat (Triticum aestivum). Here, using the same multi-location trials (4 years, 11 locations, and 192 cultivars), we report the factors that are associated with the conformation (Conf) of the polymers, which is the slope of Log(Rw) versus a function of Log(Mw). We found that Conf varied between 0.285 and 0.740, it had low broad-sense heritability (H2=16.8), and it was significantly influenced by the temperature occurring over the last month of grain filling. Higher temperatures were found to increase Rw and the compactness and sphericity of GPs. Alleles for both high- and low-molecular-weight glutenin subunits had a significant influence on the Conf value. Assuming a Gaussian distribution for Mw, the number of polymers present in wheat grains was computed for different kernel weights and protein concentrations, and it was found to exceed 1012 GPs per grain. Using atomic force microscopy and cryo-TEM, images of GPs were obtained for the first time. Under higher average temperature, GPs became larger and more spherical and consequently less prone to rapid hydrolysis. We propose some orientations that could be aimed at potentially reducing the impact of numerous GPs on people suffering from non-celiac gluten sensitivity.

Links between food and inflammatory bowel diseases (IBDs) are often suggested, but the role of food processing has not been extensively studied. Heat treatment is known to cause the loss of nutrients and the appearance of neoformed compounds such as Maillard reaction products. Their involvement in gut inflammation is equivocal, as some may have proinflammatory effects, whereas other seem to be protective. As IBDs are associated with the recruitment of immune cells, including mast cells, we raised the hypothesis that dietary Maillard reaction products generated through heat treatment of food may limit the colitic response and its associated recruitment of mast cells. An experimental model of colitis was used in mice submitted to mildly and highly heated rodent food. Adult male mice were divided in 3 groups and received nonheated, mildly heated, or highly heated chow during 21 days. In the last week of the study, each group was split into 2 subgroups, submitted or not (controls) to dextran sulfate sodium (DSS) colitis. Weight variations, macroscopic lesions, colonic myeloperoxidase activity, and mucosal mast cell number were evaluated at the end of the experiment. Only highly heated chow significantly prevented DSS-induced weight loss, myeloperoxidase activity, and mast cell number increase in the colonic mucosa of DSS-colitic mice. We suggest that Maillard reaction products from highly heated food may limit the occurrence of inflammatory phases in IBD patients.

In order to make concrete construction greener, new High Range Water Reducing Admixtures (HRWRAs) from natural origin-should be developed. Some natural polysaccharides and their derivates have interesting properties which explain their growing use in the field of materials. Their use is not only linked to the biodegradable and atoxic aspect but is also linked to the fact that they can confer new properties to cement-based materials. In the presented study, starch has been chosen as main polysaccharide chain. Starch has first been used without any modification, and then with different grafted substituents like acetate, maleate, succinate, sulfonate to mimic the structure of petrochemical HRWRAs. Some tests have been done to evaluate the potential effect of these biobased derivatives as new HRWRAs. Some of the starch-based polymers were also evaluated in a commercial self-leveling compound. Results show that a graft of sulfopropyle or sulfobutyle side chains on a starch polymer can lead to slump flows on grouts comparable with the ones obtained on PolyNaphtalene Sulfonate (PNS) based grouts, and also that starch-sulfobutyle or starch-maleate can potentially replace casein in self-leveling compounds.

A series of almost fully substituted Fatty Acid Starch Esters (FASEs) has been obtained in a homogeneous LiCl/DMAc medium by grafting octanoyl (C8), lauroyl (C12) and palmitoyl (C16) chlorides onto 3 starch species: Amylo-Maize, Potato and Waxy Maize. Structure-property relationships of FASEs are investigated as a function of both fatty acid chain length and amylose/amylopectin ratio of the starch. The structural study has revealed a layered type organization in which starch chain planes are separated by fatty chains. The latter are interpenetrated and/or tilted for FASE-C16 whatever the origin of the starch is, and fatty chains partially crystallizes into a structure with hexagonal symmetry. FASEs with C8 and C12 side chains are totally amorphous. The mechanical behavior of FASEs is shown to depend on both side chain length and amylose/amylopectin ratio, and an increase in material ductility is observed at increasing amylose content for C8 and C12 side chains.

6-Azido-6-deoxy- d -galactitol and d -mannitol were obtained quantitatively via the reduction of the corresponding 6-azido-6-deoxy- d -hexono-1,4-lactones, and 6-azido-6-deoxy- d -glucitol was obtained by the reduction of 6-azido-6-deoxyglucose in good yields. The reduction of monoazidodeoxyhexitols by catalytic hydrogenation gave the monoaminohexitol analogues in 95–98% yields. Oxidation of these afforded the corresponding 6-amino-6-deoxy- d -aldonic acids in moderate yields. Alternatively, saponification of 6-azido-6-deoxy- d -hexonolactones gave 6-azido-6-deoxyaldonic acid salts which, after reduction followed by neutralization, led to the expected compounds in 82–88% overall yields.

International audience

Resume Position du probleme La question des biais constitue un enjeu methodologique central pour l’epidemiologie. Cependant, l’histoire de ce concept n’a fait l’objet que de rares etudes. De plus, la definition classique du biais comme deviation systematique des resultats ou des inferences par rapport a la verite, telle qu’elle peut apparaitre dans les dictionnaires d’epidemiologie, ne semble correspondre ni a la maniere dont les epidemiologistes l’utilisent en pratique, ni aux differentes definitions qui jalonnent l’histoire de l’epidemiologie. Il s’agit donc d’expliquer ce paradoxe. Methodes Cet article historique et epistemologique propose d’analyser, depuis les articles classiques des annees 1950 sur le lien entre tabagisme et cancer du poumon jusqu’aux manuels d’epidemiologie les plus recents, les diverses occurrences du mot « biais » ainsi que la maniere dont les epidemiologistes utilisent, definissent et rectifient ce concept au fil du temps. Resultats Nous montrons que l’article de D.L. Sackett de 1979, consacre aux biais dans la recherche etiologique, vient clore, au moins provisoirement, une reflexion amorcee trente annees auparavant en epidemiologie populationnelle. Plus precisement, nous montrons que la definition donnee par Sackett du biais se construit moins en relation avec les besoins et les buts de l’epidemiologie populationnelle que de ceux de l’epidemiologie clinique. Au meme moment, le concept de biais est redefini au sein de l’epidemiologie populationnelle, notamment par K.J. Rohtman, comme une menace a la validite interne d’une etude, dans le cadre d’une redefinition de l’etude epidemiologique comme exercice de mesure. Conclusion Ainsi, il convient de distinguer entre deux concepts de biais : un concept epidemiologique de biais, concu comme un defaut de validite interne d’une etude observationnelle ; et un concept medical de biais, concu comme un ecart par rapport a la verite. Le premier porte sur le plan et la methodologie des etudes epidemiologiques ; le second est plus general et invite les epidemiologistes et les medecins a une certaine forme de scepticisme, voire de criticisme, envers leurs propres inferences.

The study aims to validate an original bio-based material, obtained by grafting fatty chains, and more especially lauric chains (C12) onto cellulose, for medical applications. The mechanical properties of the synthesized cellulose laurate (C12) are close to those of petrochemical ones such as low density polyethylene. This cellulose-based polymer is transparent, flexible, and hydrophobic. To evaluate the stability of the cellulosic films in biological fluids the samples are soaked in simulated body fluid or blood plasma for a few hours to 6 months, and then submitted to mechanical and chemical analyses. The simultaneously performed cytocompatibility tests were the colony-forming viability, the vitality and cell proliferation tests using NIH 3T3 fibroblasts and MC 3T3 osteoblast-like cells. The results show the stability, the biocompatibility, and the noncytotoxicity of the synthesized cellulose laurate films. This biomaterial may so be considered for surgical applications.

International audience; The use of the term "heavy metal" is regularly questioned by the scientific community. Here, we followed the evolution (1970-2020) in the number of published papers including this term in their title. Thus, we can evidence a continuous, albeit sometimes stabilizing, increase especially in environmental journals. After several other warning opinions, we propose that it should be replaced in the scientific literature by terms like "metal", "metalloid", "trace metal elements" or "potentially toxic element".

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The purpose of this study was to evaluate how the different phosphorus fractions in soils contribute to plant uptake, based on the combination between the sequential P fractionation developed by Hedley and path analysis. Successive crops were grown on soil samples with different P legacies, taken from the 0.00–0.10 m layer of an untilled Latossolo Vermelho (Rhodic Hapludox). The experimental treatments consisted of three annual P rates (0 kg P ha−1–P0; 157 kg P ha−1–P157; 314 kg P ha−1–P314). In a greenhouse, 15 successive crops of millet, black oat, corn, soybean, crotalaria and rye were grown in pots, with six replications. Phosphorus fractions in the soil were evaluated before the first crop and after the third and 15th crop. At the beginning of cultivation, the labile P fractions were buffered by the less labile P fractions in soils fertilized with the highest P rate (P314). After the 15 crop cycles, labile P was buffered, mainly by labile and non-labile organic P fractions. In soils without previous P fertilization and intermediate fertilizer rates, there was a significant contribution of organic P fractions to the moderately plant-available inorganic P pool. The organic P fraction only contributed to plant nutrition in soils fertilized with high P rates after depletion of the inorganic P pool. The conclusion was drawn that all soil P fractions can potentially provide plants with P, whereas the contribution of these P fractions depends on the P fertilization history.

Due to increased drought frequency following climate change, practices improving water use efficiency and reducing water-stress are needed. The efficiency of organic amendments to improve plant growth conditions under drought is poorly known. Our aim was to investigate if organic amendments can attenuate plant water-stress due to their effect on the plant-soil system and if this effect may increase upon ageing. To this end we determined plant and soil responses to water shortage and organic amendments added to soil. We compared fresh biochar/compost mixtures to similar amendments after ageing in soil. Results indicated that amendment application induced few plant physiological responses under water-stress. The reduction of leaf gas exchange under watershortage was alleviated when plants were grown with biochar and compost amendments: stomatal conductance was least reduced with aged mixture aged mixture (-79 % compared to -87 % in control), similarly to transpiration (-69 % in control and not affected with aged mixture). Belowground biomass production (0.25 times) and nodules formation (6.5 times) were enhanced under water-stress by amendment addition. This effect was improved when grown on soil containing the aged as compared to fresh amendments. Plants grown with aged mixtures also showed reduced leaf proline concentrations (two to five times) compared to fresh mixtures indicating stress reduction. Soil enzyme activities were less affected by water-stress in soil with aged amendments. We conclude that the application of biochar-compost mixtures may be a solution to reduce the effect of water-stress to plants. Our findings revealed that this beneficial effect is expected to increase with aged mixtures, leading to a better water-stress resistance over time. However, while being beneficial for plant growth under water-stress, the use of amendments may not be suited to increase water use efficiency.

Biosorbent materials represent an interesting alternative to classic methods of metal removal from industrial effluents. Acacia biomass showed a higher absorption capacity for heavy metals than living biomass. This study aimed to evaluate the bioadsorption of Lead and Cadmium onto Acacia Gummifera gum, using batch experiment. The structural characterization of the biosorbent was carried out using FT-IR, SEM, BET, TGA and DSC analysis. The adsorption equilibrium was reached within 15 min. A maximum uptake of 18.3 mg.g−1 Pb2+ and 9.57 mg.g−1 Cd2+ was achieved at pH 6.5. The metal ions seemed to be removed exclusively by ion exchange, physical sorption and chelation. The biomass of A. Gummifera powder was found to be effective for lead and cadmium removal with respectively 97% and 86% sorption efficiency at a concentration of 100 mg/L, in aqueous media. Parameters affecting adsorption capacities such as biosorbent dosage, initial metal concentration, temperature, and pH are discussed in detail. Furthermore, adsorption thermodynamics, kinetics, and equilibrium were studied and fitted by different models. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms were used to compare adsorption data at equilibrium. The adsorption kinetics data were found to be best fitted by the pseudo-second-order model, and the adsorption isotherm was well fitted with the Langmuir model. The calculated thermodynamic parameters (ΔG0, ΔS0 and ΔH0) indicated a spontaneous and exothermic biosorption of both metal ions onto Acacia Gummifera. Moreover, chromatograms obtained by size exclusion chromatography coupled with multi-angle laser light scattering detection system (SECMALLS) showed the formation of complexes between the arabinogalactan-peptide (AGP) and glycoprotein (GP) Acacia moieties and the two studied metal ions. The analysis of the FTIR spectra of dried Acacia and that of Acacia loaded with lead and cadmium in aqueous media suggests that the surface functional groups such as amides and carboxy groups might be involved in the metal removal process. The extent of adsorption for both metals increased along with an increase of the A. Gummifera biomass dosage. A. Gummifera biomass, which is safe, of low-cost, and highly selective, seems therefore to be a promising substrate for simultaneous trapping of Pd and Cd ions in aqueous solutions.

Yersinia enterocolitica remains a threat to public health, and a sensitive detection method is a prerequisite due to its complicated diagnosis associated with slow growth. Recently, aptamer-based detection systems have played a vital role in the development of simple, rapid, sensitive, and specific detection methods. Herein, highly specific ssDNA aptamers were screened against Y. enterocolitica at the different growth stages by whole cell-SELEX. Cells at different growth stages were harvested and incubated with an ssDNA library to get an enriched pool of specific aptamer candidates. After the 10th round of SELEX, the enriched pool was sequenced and grouped into seven families based on homology and similarity of the secondary structure. Flow cytometry analysis revealed that the aptamers M1, M5, and M7 with Kd values of 37.93 ± 7.88 nM, 74.96 ± 21.34 nM, and 73.02 ± 18.76 nM had the highest affinity and specificity to the target, respectively. The selected aptamers showed binding to the different growth stages of Y. enterocolitica with a significant increase in the gated fluorescence. Our aptamer selection strategy is convenient, and the developed aptamer can be useful for an accurate and reliable detection system.

The elevated concentrations of rare earth elements (REE) and yttrium (REE+Y) in acid mine drainage (AMD) constitute an opportunity for REE+Y recovery. However, the source and control of REE+Y signatures in AMD remains uncertain. Water, rock, sediment and sludge samples were collected from an ion-adsorption rare earth mining area to investigate REE+Y concentration and fractionation patterns in AMD. High concentrations of REE+Y occur in the pristine mine water (MW), and decrease progressively with MW passing through nitrification-denitrification (NDT) and coagulating-precipitation (CPT) treatment procedures in a water treatment plant. Concentrations of REE+Y are 1 to 3 orders of magnitude higher in MW, NDT and CPT samples than those in well water (WW), and are negatively correlated (R2 0.72) with pH (3.8 to 8.7), suggesting that an enhanced acidic dissolution of minerals contributes REE+Y to AMD from the source area. Speciation calculation indicates that REE+Y are mainly free ions and sulfate complexes in MW and NDT samples, while carbonato and dicarbonato complexes in CPT samples. Normalized REE+Y patterns of water samples show a coherent enrichment of heavy REE (HREE) over light REE (LREE) and negative Ce anomalies. HREE-enriched patterns and Ce anomalies are kept relatively constant in MW, NDT and CPT samples, despite their huge disparity in REE+Y concentrations, indicating a limited impact of preferential precipitation of LREE over HREE on REE+Y fractionations. The HREE-enriched patterns possessed by AMD are similar to those of sediment samples, while are distinct from whole rocks. These behaviors suggest a major role of sediment source in controlling REE+Y concentrations and patterns in AMD. Results of XRD show abundance of muscovite, kaolinite and feldspar in sediments. Combining to SEM-EDS examinations, minerals such as kaolinite, schwertmannite (Fe16O16(SO4)3(OH)6(H2O)10·10H2O) and ferrihydrite are suggested to be the main hosts of REE+Y in sediments. Hence, HREE-enriched patterns of AMD result from preferential leaching of HREE from sediments which accumulate REE+Y after being initially mobilized from rocks under the conditions prevailing in mine site. The free form and sulfate complexation preserves REE+Y patterns and facilitates REE+Y mobility in the AMD system. Based on the plant treatment capacity, the potentially recoverable LREE and HREE are calculated to range between 1116 g/day and 3373 g/day, and between 1288 g/day and 3764 g/day, respectively.

International audience; Addressing agriculture at the landscape level leads to dealing with agricultural landscapes, defined here as landscapes that contain mainly agricultural land uses. In this chapter, we focus on how agronomy and other disciplines have addressed to date agriculture beyond field and farm management. The landscape agronomy framework suggests that addressing agriculture at the landscape level allows farmers to be included with other stakeholders involved in spatially explicit management of natural resources. This framework also bridges gaps with other disciplines that work to describe and understand agricultural landscapes and their management. In addition to this qualitative summary of the scientific background, we present results of a bibliometric analysis that used the CorTexT platform to explore research keywords, (inter)disciplinary bridges and emerging issues related to these topics. The results highlighted the emergence of climate change, ecosystem services and management practices in the literature related to agronomic terms, especially when landscape is explicitly mentioned in publications’ titles, abstracts or keywords. In the end, we draw conclusions about potential improvements to this conceptual framework and introduce the structure of the present book about advances and challenges of a territorial approach to agricultural issues.

This study deals with the toxicity of the treated solutions of two types of dyes, namely, the anthraquinonic Reactive Bleu 19 dye (RB19) and the bi-azoic Direct Red 227 dye (DR227), which are treated in single and binary mixture systems. The target molecules were removed by the photocatalysis process using ZnO as a catalyst, which was calcined at two temperatures 250 and 420 °C (ZnO

A comment on “For NGOs, article-processing charges sap conservation funds” by Wood et al.

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International audience; Ecological engineering of degraded ecosystems often manipulates plants, with positive outcomes for their restoration or ecosystem services production. The importance of soil biota for successional plant communities has prompted consideration of direct inoculation (active) or attraction (passive) of soil organisms as a relevant restoration strategy. However, few attempts have manipulated soil invertebrates as part of nature based solutions for ecosystem restoration, despite their major role in many soil ecological processes and in plant-soil feedback processes. In addition, while ecological restoration and ecological engineering approaches successfully incorporate plant traits, soil invertebrate traits remain underused. Exploiting the functional diversity of soil communities by adopting a trait-based approach could enhance restoration of soil chemical, biological and physical properties. Here, we conduct a narrative review and identify a set of soil invertebrate functional traits with great potential in ecosystem restoration. We focus on traits related to four main ecological functions that are often at the core of restoration plans: nutrient cycling and carbon cycling, pollutant detoxification, soil structure arrangement, and biological control agent by prey/pest regulation. This paper further proposes guidelines for stakeholders that need to be addressed to successfully integrate soil organism traits into ecological engineering. Finally, we highlight main knowledge gaps and limitations currently impeding the use of soil invertebrate traits in ecological engineering, and identify avenues for future research. We especially bring out (i) that few studies still use soil invertebrates in restoration, so even fewer are based on traits, (ii) a lack of data about soil invertebrate species role in ecosystems, (iii) a lack of data about attributes from specific traits and groups in existing soil functional trait databases, (iv) the complex relationships between functions and traits and (v) that future studies are needed to demonstrate the benefits of such trait-based approaches compared to approaches relying on emblematic species.

International audience; Wheat grain storage proteins, i.e. the gluten proteins, and alpha-amylase trypsin inhibitors are partially resistant to gastrointestinal digestion. They figure among the wheat components that are potential triggers of non-celiac wheat sensitivity. To explore the digestibility of bread wheat proteins in relation to heritable plant traits, old and modern wheat varieties grown in two environments were genotyped, phenotyped, and processed into breads, which were partially digested in vitro in a system resembling human digestion. The extent of proteolysis measured after 2 h of digestion was variable. Digestion of proteins present in bread made from old wheat cultivars registered before 1960 and modern cultivars registered after 1960 was similar. No major plant trait was correlated to partial protein digestibility of bread from cultivars with high grain protein content. The protein digestibility of bread from high yield cultivars was influenced by protein composition, as well as the genetic distance per chromosome from a reference variety. Improving high yield cultivars by breeding for highly digestible proteins might help to mitigate adverse reactions to a range of wheat proteins in susceptible individuals.

Background: Earth sciences is one of those sensitive field sciences that are closely needed to solve local problems within local physical and social settings. Earth researchers find state-of-the-art of topics in earth sciences by using scientific databases, conduct research on the topics, and write about them. However, the accessibility, readability, and usability of those articles for local communities are major problems in measuring the impact of research, although it may be covered by well-known international scientific databases. Objectives: To ascertain empirically whether there are differences in document distribution, in the proportions of openly accessible documents, and in the geographical coverage of earth sciences topics as revealed through analyses of documents retrieved from scientific databases and to propose new measures for assessing the impact of research in earth sciences based on those differences. Methods: Relevant documents were retrieved using ‘earth sciences’ as a search term in English and other languages from ten databases of scientific publications. The results of these searches were analysed using frequency analysis and a quantitative- descriptive design. Results: (1) The number of articles in English from international databases exceeded the number of articles in native languages from national-level databases. (2) The number of open-access (OA) articles in the national databases was higher than that in other databases. (3) The geographical coverage of earth science papers was uneven between countries when the number of documents retrieved from closed-access commercial databases was compared to that from the other databases. (4) The regulations in Indonesia related to promotion of lecturers assign greater weighting to publications indexed in Scopus and the Web of Science (WoS) and publications in journals with impact factors are assigned a higher weighting. Conclusions: The dominance of scientific articles in English as well as the paucity of OA publications indexed in international databases (compared to those in national or regional databases) may have been due to the greater weighting assigned to such publications. Consequently, the relevance of research reported in those publications to local communities has been questioned. This article suggests some open-science practices to transform the current regulations related to promotion into a more responsible measurement of research performance and impact.

International audience; Three cubic-meters of CO2-saturated water was injected into a subsurface fractured aquifer in a post-mined area, using a push-pull test protocol. Groundwater samples were collected before and after CO2-injection to quantify geochemical changes. CO2-injection initially reduced the pH of water from 7.3 to 5.7, led to the enrichment of major ions (Ca2+, Mg2+, and alkalinity), and dissolved trace metals (including Fe, Mn, As, and Zn) in the groundwater. Rare earth elements (REE) and yttrium concentrations were also measured in these samples before and after CO2 perturbation, to evaluate their behavior. An enrichment of total Y plus REE (REY) occurred. REY fractionation was observed with higher heavy REE (HREE) enrichment compared to light REE (LREE), and significant variations in La/Yb and Y/Ho ratios were observed following CO2 perturbation. Enrichment by a factor of three was observed for Y, Lu, and Tm, and by nearly one order of magnitude for Dy and Yb. A geochemical model was used to evaluate the amount of REE aqueous ions complexed throughout the experiment. Modeling of the results showed that speciation of dissolved REE with carbonate, along with desorption from iron oxyhydroxide surface were the main factors controlling REE behavior. This study increases an understanding of dissolved REE behavior in the environment, and the potential use for applying iron oxides for REE recovery from mine drainages. Furthermore, the description of REE fractionation patterns may assist in surveying CO2 geological storage sites, surveying underground waste disposal sites, and for understanding the formation of ore deposits and fluid inclusions in geological formations.

International audience; Sewage sludge is a phosphorus (P) source alternative to P fertiliser derived from rock phosphate, but its impact on soil processes driving P cycling in agroecosystems requires further study. In order to optimise the use of sludge for sustainable P fertilisation, we need to elucidate the drivers of P dynamics. The present study aims at determining how different sludges (heated sludge, HS and composted sludge, CS) affect soil P pools and dynamics. A field experiment was established and soil was amended either with sludge or with inorganic P (triple superphosphate, TSP). Soil samples were collected five times during a vegetation period, and analysed for Hedley P fractions, microbial P and phosphatase activity. Phosphorus dynamics in soil was strongly influenced by P concentrations in sludge. About one year after application, sludge with the highest P concentration (HS) was as effective as TSP to improve soil P availability. The P source of TSP was immediately available for plant uptake, but the high phosphatase activity of the HS treatment evidenced that soil microorganisms released phosphatases which can hydrolyse HS-derived organic P compounds. In addition, the high content of microbial P in the HS treatment suggests that soil microorganisms assimilate P into their own biomass. By contrast, sludge with the lowest P concentration (CS) enriched primarily the weakly-soluble soil P fractions, resulting in lower P availability compared with that in the TSP treatment. Our findings suggest that both high P concentration and slow, but continuous microbial breakdown of organic P substrates derived from HS allow using this resource as an important source for plant mineral nutrition. This study stresses the need to both characterise P concentrations and P forms in sludge, prior to their application in the field.

International audience; Background and aims: Pioneer plants may improve the ecological restoration of degraded ultramafic areas by plant-soil interaction processes. In this study, we assess the effect of the pioneer actinorhizal tree C. terminale (Casuarinaceae) on the recovery of plant communities and soil functions on degraded tropical ultramafic sites.Methods: Soil and plant samples were collected along a tree-age gradient in two degraded ultramafic sites in Sabah (Northern Borneo, Malaysia): a Technosol and a Leptosol. Chemical composition of plants and soils, and biological activity of soils were assessed at both sites. Plant colonisation was assessed by plot vegetation surveys.Results: An improvement in soil fertility parameters (pH reduction from 8.5 to 6.8, an increase in the concentrations of several nutrients and enhanced soil enzyme activities) was observed along the C. terminale age gradient. However, plant cover and diversity was only improved around mature trees at the site that was not impacted by mining.Conclusion: C. terminale promotes the recovery of several soil functions, mainly related to the storage and recycling of N, P, K, S. Besides plant-soil feedback, other environmental factors (i.e. exposition to sunlight, drought) may play an important role on revegetation of ultramafic soils.

International audience; The adoption of precision farming techniques (PFTs) has been widely studied targeting specific PFT or farming systems along with the potential benefits of these PFTs in terms of yield or input use. However, few studies have examined how PFTs are adopted and used at the farm level. In this study a preliminary investigation was made of on-farm PFT uses in the Oise region (northern France). Three main PFTs were identified in the area: Global Navigation Satellite Systems (GNSS) guidance, section control, and variable rate (VR) application. For each farm, the use of every PFT was defined by the technical characteristics of the equipment, the field operation(s) concerned, the targeted crop(s), the aim of the use, the PFT adoption drivers, and the perceived impacts by the farmers. These different variables were combined into a typology of PFT uses. The results show that most of the farms combined GNSS guidance for all technical operations and section control, whereas VR application was less common. Section control was largely used by farmers for liquid fertilizers and phytochemical spraying. The typology shows three to five types of use for each PFT, which differ in terms of technique adoption drivers, e.g. reducing on-farm work or adaptation to field morphology. According to literature, economic impacts were found to be the most frequent, however farmers seemed unable to quantify them. Social impacts such as reduced work time and fatigue were also frequent and are becoming the main motivation for using PFT on farms studied. Further research is needed to assess the use trajectories of PFT along with the motivations of each PFT use.

In order to replace wood in particleboard manufacturing, two agricultural by-products were studied: the flax shives and the sunflower bark, which are abundant, renewable and little valorized raw materials. Sunflower bark in particular is very few studied. This study will demonstrate the possibility of using sunflower bark in particleboards and how to modulate the manufacturing process to take the benefits of both studied agroresources. These plant based particles present interesting porous structures for using as materials for building insulation or as furniture. To obtain totally biosourced materials, the plant based particles were self-bound by a thermocompression process with water. The properties of these materials were compared with particleboards made of the same plant based particles with a classical urea-formaldehyde binder. Particleboards of two target densities are compared: 350 and 500 kg m−3. Both agroresource materials do not present the same behavior to self-binding or classical binding. Flax shives are more adapted to self-binding process thanks to their biochemical composition and their morphological structure. These different boards were characterized according to mechanical and thermal properties, resistance to water and to fire. The type of agroresource or of binder does not influence the thermal conductivity. The denser binderless boards show better resistance to fire. The main defect of binderless boards is their too low resistance to water compared to boards made with a synthetic binder.

International audience; Conventional, intensively managed coffee plantations are currently facing environmental challenges. The use of shade trees and the organic management of coffee crops are welcome alternatives, aiming to reduce synthetic inputs and restore soil biological balance. However, little is known about the impacts of the different types of shade tree species on soil functioning and fauna. In this paper, we assess soil nutrient availability and food web structure on a 17-year old experimental coffee plantation in Turrialba in Costa Rica. Three shade types (unshaded coffee, shaded with Terminalia amazonia, and shaded with Erythrina poepiggiana) combined with two management practices (organic and conventional) were evaluated. Total C and N, inorganic N and Olsen P content, soil pH, global soil fertility, and nematode and microarthropod communities were measured in the top 10 cm soil layer, with the objective of determining how shade tree species impact the soil food web and soil C, N and P cycling under different types of management. We noted a decrease in soil inorganic N content and nematode density under conventional management (respectively -47% and -91% compared to organic management), which suggested an important biological imbalance, possibly caused by the lack of organic amendment. Under conventional management, soil nutrient availability and fauna densities were higher under shade, regardless of the shade tree species. Under organic management, only soils under E. poeppigiana, a heavily pruned. N-2 -fixing species, had increased nutrient availability and fauna density, while T amazonia shade had a null or negative impact. The effects of coffee management and shade type on soil nutrient availability were mirrored by changes in soil food web structure. Higher fertility was recorded in soil with balanced food webs. These results emphasize the importance of the choice of shade tree species for soil functions in low input systems, more so than in fertilized systems

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