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Electrospun scaffolds exhibiting high physical performances with the ability to support cell attachment and proliferation are attracting more and more scientific interest for tissue engineering applications. The inclusion of inorganic nanoparticles such as nanosilica and nanoclay into electrospun biopolymeric matrices can meet these challenging requirements. The silica and clay incorporation into polymeric nanofibers has been reported to enhance and improve the mechanical properties as well as the osteogenic properties of the scaffolds. In this work, for the first time, the physical and biological properties of polylactic acid (PLA) electrospun mats filled with different concentrations of nanosilica and nanoclay were evaluated and compared. The inclusion of the particles was evaluated through morphological investigations and Fourier transform infrared spectroscopy. The morphology of nanofibers was differently affected by the amount and kind of fillers and it was correlated to the viscosity of the polymeric suspensions. The wettability of the scaffolds, evaluated through wet contact angle measurements, slightly increased for both the nanocomposites. The crystallinity of the systems was investigated by differential scanning calorimetry highlighting the nucleating action of both nanosilica and nanoclay on PLA. Scaffolds were mechanically characterized with tensile tests to evaluate the reinforcing action of the fillers. Finally, cell culture assays with pre‐osteoblastic cells were conducted on a selected composite scaffold in order to compare the cell proliferation and morphology with that of neat PLA scaffolds. Based on the results, we can convince that nanosilica and nanoclay can be both considered great potential fillers for electrospun systems engineered for bone tissue regeneration.

The galvanic deposition method was used to deposit Hydroxyapatite/Chitosan/Collagen coatings on 304 stainless steel. Galvanic deposition is an alternative and valid way to fabricate bio-coatings with high biocompatibility and good anticorrosion properties. Physical-chemical characterizations were carried out to investigate chemical composition and morphology of the samples. Coatings consist of a mixture of calcium phosphate (Brushite and Hydroxyapatite) with chitosan and collagen. Corrosion tests were performed in the simulated body fluid (SBF) after different aging times. Results show that, in comparison with bare 304 stainless steel, coating shifts corrosion potential to anodic values and reduces corrosion current density. Nevertheless, the aging in SBF led to a completely conversion of brushite into hydroxyapatite. The release of metal ions, measured after 21 days of aging in SBF solution, is very low due to the presence of coating that slow-down the corrosion rate of steel.

During the last decades, biomaterials have been deeply studied to fabricate and improve coatings for biomedical devices. Metallic materials, especially in the orthopedic field, represent the most common materials used for different type of devices thanks to their good mechanical properties. Nevertheless, low/medium resistance to corrosion and low osteointegration ability characterizes these materials. To overcome these problems, the use of biocoatings on metals substrate is largely diffused. In fact, biocoatings have a key role to confer biocompatibility features, to inhibit corrosion and thus improve the lifetime of implanted devices. In this work, the attention was focused on Hydroxyapatite-Chitosan (HA/CS) and Hydroxyapatite-Polyvinylacetate (HA/PVAc) composites, that have been studied as biocoatings for 304 SS based devices. Hydroxyapatite was selected for its osteoconductivity due to its chemical structure similar to bones. Furthermore, Chitosan and Polyvinylacetate are largely used yet in medical field (e.g. antibacterial agent or drug deliver) and in this work were used to create a synergic interaction with hydroxyapatite to increase the strength and bioactivity of coating. Despite bio-coatings were obtained by different techniques, in this work, they were fabricated by galvanic deposition process that has different advantages, among which it does not require external power supply. It is a spontaneous electrochemical reaction in which materials with different standard electrochemical potential were short-circuited and immersed in an electrolytic solution. Electrons supplied by the anodic reaction at the less noble electrode flow to cathode where they oxidize the less noblest ions in solution. SEM, EDS, XRD and RAMAN were performed for chemical-physics characterization of biocoatings. Polarization and impedance measurements have been also carried out to evaluate corrosion behavior. Besides, in-vitro cytotoxicity assays have been done for the biological features.

The purpose of this article is to make a brief compilation of the main problems that have inspired research in agrifood economics over the last 50 years. Furthermore, the article aims to highlight the efforts that have allowed agriculture and food to prosper with a human face, through training and research networks in agro-food economics, as well as the main contributions in this field in the emblematic case of the Center for Agrifood Research Edgar Abreu Olivo of the Universidad de Los Andes (ULA), Venezuela, during the last 25 years. Fifty years ago, as a young teacher, I used to begin my lessons by asking myself and my students about the transformation of the world's food systems and their future evolution. The question later divided the economists of the day. Some predicted that technology, combined with market forces under the capitalist model, would gradually replace the family, artisanal and small and medium-sized enterprise (SME) forms, which then accounted for a significant share of global food production. Others, more pragmatic, raised the fact that primary food production would be left in the hands of individual entrepreneurs (artisans, peasants and SMEs). They had reason to justify this view in terms of capital, labour and knowledge requirements. They also pointed out that agricultural chains would allow large processing and marketing companies to control the chains according to their interests, and that the balance of power generated would allow them to obtain substantial profits from the capital generated without assuming the main risks. Since then, half a century has passed and the concept of agri-food economics has gradually taken shape. By the beginning of the century, ���feeding the world��� had become a strategic issue for humanity. The article makes a compilation of the road travelled and shows the teaching and research efforts that have undoubtedly contributed to the emergence of the new science, which the Agrifood Economy has become., A10 D23 D29 O32 Q10 Q16 Q17 Q18 Q19 Q20 Q56

One of the most reliable techniques for the preparation of biodegradable scaffoldssuitable for tissue engineering applications (e.g. regeneration of wounded/damagedtissues) is based on liquid/liquid phase separation of ternary solvent/antisolvent/polymersolutions. In particular, two phase separation protocols are examined here: ThermallyInduced Phase Separation (TIPS) and Diffusion Induces Phase Separation (DIPS). According to the former protocol, a thermodynamically stable polymeric ternarysolution is brought below its metastability/instability point (spinodal/binodal curve) byquench in a cooling medium: under opportune conditions, a foam-like structure is formedby nucleation and 3-D growth of the polymer lean phase, which, after solvent removal byrinsing and drying, will constitute the voids of the as-generated "open-pore" architecture. Two ternary polymeric solutions were examined in detail: Poly-L-Lactic Acid(PLLA)/Dioxane (solvent)/TetrahydroFurane (THF, antisolvent) andPLLA/Dioxane/Water (antisolvent). For both systems (PLLA/Dioxane/THF andPLLA/Dioxane/Water) the solvent (dioxane) to antisolvent (THF or water) ratio and thepolymer concentration were varied; moreover, different cooling paths from the stableternary solution down to the instable zone were examined.In order to tune the biodegradation kinetics of the foams, PLLA/PLA blends invarious proportions were dissolved in the dioxane/water system. As for the latter phase separation protocol, vessel-shape PLLA (and PLLA/PLAblends) scaffolds for vascular tissue engineering applications were produced byperforming a dip-coating around a nylon fibre, followed by a Diffusion Induced PhaseSeparation (DIPS) step, where samples were pool immersed in a bath containing solventand antisolvent in different proportions, thus inducing phase separation by changing thesolvent power.Structure and morphology of the resulting foams were characterized by apparentporosity, Scanning Electron Microscopy (SEM), gas/liquid porometry, calorimetricanalysis (Differential Scanning Calorimetry, DSC), Wide Angle X-ray Diffractometry(WAXD), Optical Microscopy (OM), Confocal Laser Microscopy. Biodegradationkinetics was studied by monitoring weight loss on a dry basis with time under differentenvironmental conditions. © 2011 by Nova Science Publishers, Inc.

Nanogels (NGs) synthesized by pulsed electron-beam irradiation of semi-dilute poly (N-vinyl pyrrolidone) (PVP) aqueous solutions, at relatively low energy per pulse and doses within the sterilization dose range, represent a very interesting family of polymeric nanocarriers. Ionizing irradiation-induced crosslinking of PVP allows to control particle size, and surface chemistry of the polymer nanoparticles without making use of catalysts, organic solvents or surfactants, and with beneficial effects onto the purity and hence biocompatibility of the final products obtained. Furthermore, the availability of reactive functional groups, either generated by the radiation or purposely grafted via copolymerisation with suitable functional monomers enables the conjugation of therapeutics drug, that make them suitable nanocarriers for biomedical applications. In particular, we have developed a carboxyl-functionalized nanogel variant for glutathione-mediated delivery of a chemotherapeutic agent, Doxorubicin. The drug is linked to the nanoparticles through a linker containing a cleavable disulphide bridge, aminoethyldithiopropionic acid (AEDP). In vitro drug release experiments have shown that glutathione can induce the release of Doxorubicin, through the reduction of the disulfide bridge. These results suggest that such redox-responsive nanoparticles can deliver doxorubicin into the nuclei of tumor cells, thus inducing inhibition of cell proliferation, and provide a favourable platform to construct nanoscalar drug delivery systems for cancer therapy.

In the last decades, molecular biology allowed the development of innovative protocols in the field of conservation/restoration of cultural assets. In this work new hydrolyses, isolated from marine invertebrate organisms, are applied to remove protein layers form works of art surface. Proteolytic zymography assay evidenced that these enzymes are active in a broad temperature range, between 4 degrees and 37 degrees C. The enzymatic cleaning by these proteases, tested on wooden furniture of the second half of the eighteenth century showed positive results, without needing to heat the enzyme solution or the surface on which they were applied. The present report proposes novel proteases more appropriate than other, which usually are active at temperature >= 37 degrees C, for a controlled removal of protein layers from wooden painted artifacts.

In the last decades molecular biology allowed the development of innovative protocols in the field of conservation/restoration of cultural assets. In this work we presents novel hydrolyses isolated from marine invertebrate organisms, whose protease activity was previously tested in laboratory by zymography on polyacrilamide gel (in presence of 0.1 of gelatin) Very interesting these enzymes are activated/work in a range of temperatures between 4 ° C and 37 ° C. In this study two sets of proteases were applied, to bio-clean works of art surfaces, at the environments temperature (19° to 25.5° C). Before remove, the water-soluble components of the layers have been analyzed by high-pressure size molecular exclusion chromatography (SEC-HPLC, BioSuite 250 to 10 μm SEC 7.5 x 300 mm Waters), followed by electrophoresis on acrylamide gel (SDS-PAGE 15%) and silver staining of the bands. The results reveal the presence of protein molecules in concentrations between 24 and 110 μg/m, and molecular weight between 20-35 kDa and 60-90 kDa. The enzymatic cleaning showed skillful results, without providing the heating of the enzyme solution or of the surface on which they were applied. The particular feature makes these protease more appropriate then the other, which usually are activated at temperatures >37 ° C. Our hypothesis is that these enzymes will implement the efficiency of enzymatic cleaning protocols, according to the conservative restoration procedures.

One of the best successful examples of cell therapy is represented by islet transplantation since 1990. However islet isolation methods are not completely standardized yet. More than half of isolation procedures failed to isolate adequate islets for transplantation, due to variable pancreas conditions and to unpredictable enzymatic blend efficiency. Enzymes used for pancreas digestion include collagenases and neutral proteases: their composition and activity are largely variable between different batches. We set up a new in vitro method to better in vitro characterize enzymatic blend before its use in human pancreas. In our experimental approach human immortalized cells (ECV-304) or human islets were coltured within a 3-D type-I collagen gel in 96 wells plate. After one culture day, cells and/or islets were treated with different commercial enzymes (Liberase, Serva NB1 premium grade, Collagenase type P, Thermolysin, Neutral proteases) from different batches at different concentrations and for different times. Digestion of 3-D type-I collagen fibril gels were monitored by optical dense absorption to a fix l; morphology of released cells and/or islets were valued by confocal microscopy analyses. Cells were immunostained about expression of some adhesion molecules, like: integrins, cadherins and associated molecules, catenins, to appreciate cells morphology and islets aggregation modifications. Cell viability was assessed by SYTO 13 and ethidium bromide. We found that Neutral proteases is less pure and more toxic than Thermolysin: it has collagenase activity and it significantly decreases cell viability. Even viable cells after neutral proteases showed an alterated morphology with an impairment of cell to cell communications. We, also, observed an higher efficiency in extraction by Serva NB1 compared to Liberase and Collagenase type P, used in the same experimental conditions. By this in vitro method we were able to compare the minimal active enzyme concentration of different enzyme blends: we found that Liberase has its best value as number of extracted cell/alive cells in 130 mg/ml; while, in actual protocols for human pancreas is used to 1.3 mg/ml. Preliminary results showed a correlation between data achieved in cell lines with those of human islets, thus confirming the potential predictive role of this method for the selection of enzymes for human pancreas digestion purpose.

Recently, we have discovered that neuropeptide Y (NPY), a sympathetic neurotransmitter, is also present in human umbilical endothelial cells (HUVECs), and is potently chemotactic and angiogenic by acting on one or several of Y1-Y5 receptors. In HUVECs, NPY is co-localized with dipeptidyl peptidase IV (DPPIV) which cleaves Tyr(1)-Pro(2) from NPY(1-36) to form NPY(3-36) resulting in the formation of a non-Y1 receptor agonist, which remains angiogenic. Presently we studied the effects of DPPIV's blockade using monoclonal antibodies (mAbs) on migration of HUVECs in response to NPY(1-36) or NPY(3-36) following cell wounding. Both peptides caused similar dose-dependent increases in cell migration (+80% at 0.1 nM) 12 h after wounding. DPPIV mAbs, E19 and E26, significantly reduced HUVEC's migration below that of the untreated cells, and blocked responses to NPY(1-36) but not NPY(3-36). Enhanced expression of DPPIV was found in the migrating cells and in cells with their protrusions at the edge of the wound (immunostaining and Western blot). Thus, DPPIV's expression is stimulated by endothelial wounding and its enzymatic activity is required for NPY-mediated chemotaxis. Furthermore, this suggests that non-Y1 receptors activated by NPY(3-36) (Y2, Y3 and/or Y5) mediate angiogenic effects of NPY.

Conclusions: Endothelia cells in sparse culture are migratory and increase the production of gelatinases of serine- and metallo-classes in membrane vesicles. Collectively, proteases associated with membrane vesicles degrade extracellular matrix components including type-I and type-IV collagens, laminin and fibronectin. Inhibitor studies suggest the existence of small gelatinases that were derived from these serine- and metallo-proteases. Thus, further studies are warranted to demonstrate the cooperative action of metallo- and serine proteases on cell surfaces and in extracellular vesicles during endothelial cell migration in 3D collagenous matrices, and potential proteolytic activation mechanism for these cell surface proteases.

We have identified and partially characterised two antigens, extracted with 3% butanol, from Paracentrotus lividus embryos dissociated at the blastula stage, and encoded by the cDNA clones previously described as bep1 and bep4 (bep-butanol extracted proteins). The cDNA fragments containing the specific central portions of bep1 and bep4 were expressed as MS2 polymerase fusion proteins in Escherichia coli. These two fusion proteins, called 1C1 (bep1) and 4A1 (bep4), were injected subcutaneously into rabbits and the corresponding polyclonal antibodies generated. Western blot analysis of proteins, extracted with 3% butanol, from sea urchin embryos at the blastula stage (b.e.p.), established that both antibodies recognize two 33 KDa proteins. Reducing and non-reducing electrophoretic conditions show that both antibodies against bep1 and bep4 related proteins react also with a protein band of a molecular weight 66 KDa, indicating that these two antigens probably exist as dimers. Immunolocalization with anti 1C1 and 4A1 antibodies shows the presence of the related antigens also on the cell surface. Fab fragments of the polyclonal antibodies against 1C1 and 4A1 inhibited reaggregation of sea urchin embryonic cells, dissociated from blastula stage embryos. This prevention of reaggregation indicates that these proteins probably play a role in cell interaction during sea urchin embryonic development.

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International audience; Ce document, réalisé à l'occasion de l'hommage à Louis Malassis organisé le 12 juin 2008 à Montpellier, est le fruit de la collaboration d'un petit groupe de personnes appartenant à Agropolis MUSEUM, Agropolis international et à l'Institut Agronomique Méditerranéen de Montpellier. Il comprend essentiellement des textes écrits par Louis Malassis sur les projets qu'il a menés en fin de carrière - à savoir Agropolis et Agropolis Museum. On trouve aussi le projet de Faculté Agronomique pour lequel il plaidait encore devant le préfet en 2000 mais resté non abouti. Un hommage de ses collègues chercheurs, souvent co-auteurs de ses publications, met en avant ses qualités d'innovateur et de précurseur au niveau de l'enseignement, de la recherche et de la science au service du développement. Une brève biographie et une liste de publications éditée et non éditée et disponible dans les organismes d'Agropolis clôturent le document

International audience; Ce DVD contient textes et images visant à mieux nous faire connaître la vie de Louis Malassis, sa pensée, ses combats et ses principaux projets. Le film de 13 minutes retrace son parcours depuis sa jeunesse en Bretagne et son engagement pour les paysans là-bas et sur le terrain de par le monde. Il résume sa philosophie dans la trilogie qu'il écrit en 2001, 2004 et 2006 (avec le titre prémonitoire de : Ils vous nourriront les paysans du monde si…). La construction du projet Agropolis (1986) puis celle d'Agropolis Museum (1992) est celle d'un visionnaire qui croît dans les synergies et la mise à disposition de la science aux citoyens. Les textes d'accompagnement de ces projets qu'il écrivit plus tard sont aussi en ligne. Les différents hommages font ressortir les points forts de sa philosophie et ses apports scientifiques dans l'économie agroalimentaire et la formation. La bibliographie de sa production scientifique éditée ou seulement consultable, comme littérature grise, dans les différents instituts d'Agropolis est conséquente. Une partie des interviews qu'il réalisa dans la dernière partie de sa vie est en ligne

Endothelia cells in sparse culture are migratory and increase the production of gelatinases of serine- and metallo-classes in membrane vesicles. Collectively, proteases associated with membrane vesicles degrade extracellular matrix components including type-I and type-IV collagens, laminin and fibronectin. Inhibitor studies suggest the existence of small gelatinases that were derived from these serine- and metallo-proteases. Thus, further studies are warranted to demonstrate the cooperative action of metallo- and serine proteases on cell surfaces and in extracellular vesicles during endothelial cell migration in 3D collagenous matrices, and potential proteolytic activation mechanism for these cell surface proteases.

International audience

National audience; En lançant, avec le concours de l'Union européenne, le programme d'action régionale (PAR), le Ciheam entendait accompagner le processus de construction régionale de Barcelone et contribuer, par une série d'interventions conduites dans le domaine de la formation et de la recherche, à renforcer la capacité des acteurs dans la prise de décision dans le cadre de la mondialisation. Le volet "politiques agricoles et alimentaires" a été coordonné par l'Iresa de Tunis et l'IAM de Montpellier. L'ouvrage de synthèse réunit les résultats de recherche les plus originaux. La première partie traite d'abord de l'agriculture, des politiques agricoles, et des perspectives de libéralisation (cas de la Turquie, Egypte, Maroc, Tunisie). Marchés, entreprises et consommation alimentaires constituent le noyau dur de la deuxième partie. La troisième partie aborde enfin la transformation du monde rural méditerranéen et le processus de mondialisation : systèmes de production agricoles, réorganisation foncière et organisation du développement rural. Les conclusions générales font enfin ressortir la grande diversité des pays et la difficulté de réfléchir à un futur commun. La construction d'une politique conjointe, prolongement naturel des activités de recherche, et coordonnée en matière de gestion des savoirs constitue un enjeu majeur, car elle permettra de construire une intelligence collective indispensable à un développement solidaire de l'espace méditerranéen.

National audience

This book integrates research tasks and publication resulting from PAR/PAA program of CIHEAM. It gives a report on the current state of the questions which cross the Mediterranean agriculture and rural territories: liberalization policies, markets and countries transformation process., Cet ouvrage intègre l`ensemble des travaux de recherche et de publication issus du programme PAR/PAA du Centre international des hautes études agronomiques méditerranéennes (CIHEAM) Il fait le point sur l`état actuel des questionnement qui traversent l`agriculture et les territoires ruraux méditerranéens, des politiques de libéralisation aux marchés en passant par les processus de transformation du monde rural.

National audience

National audience; L'industrie agroalimentaire constitue un secteur de premier plan dans la plupart des pays des rives sud de la Méditerranée, à la fois pour son poids en termes socio-économiques et pour ses effets d'entraînement. La structure d'offre reste très atomisée. On voit toutefois apparaître, après une phase dominée par les entreprises publiques jusqu'au début des années 90, des firmes de grande taille développées par le capitalisme privé, sous la forme conglomérale (Egypte, Maroc, Tunisie, Turquie notamment). Les multinationales originaires des pays du Nord à haut revenu sont présentes en zone méditerranéenne et limitent les opportunités des entreprises locales sur les marchés de masse. En conséquence, les auteurs font l'hypothèse d'un scénario stratégique de "contournement" basé sur des produits à forte typicité pour promouvoir l'entrepreneuriat national.

National audience; La déclaration de Barcelone des 17 et 18 novembre 1995 a instauré un partenariat euro-méditerranéen en vue de construire une zone de prospérité partagée par le biais de trois types de moyens : l'instauration progressive d'une zone de libre-échange, la coopération et la concertation économique et la coopération financière. Cependant les premiers résultats de ce partenariat sont décevants. Les échanges agro-alimentaires sont dans une situation déficitaire, l'aide au développement a diminué tandis que les investissements directs à l'étranger (IDE) sont inégalement répartis entre les deux rives de la Méditerranée et touchent très peu le secteur agro-alimentaire. Le texte propose en conclusion les stratégies de développement agro-alimentaire qui ont été à l'ordre du jour lors du séminaire d'Alger organisé par le CIHEAM en avril 2002 ; ces stratégies tiennent compte des secteurs social, économique et environnemental.

International audience; Le document présente une analyse prospective conduite par une équipe de quatre universitaires marocains et français sur le système agroalimentaire au Maroc, selon une approche combinant la méthode SWOT et celle des scénarios. Cette analyse a été discutée lors d'un séminaire rassemblant des décideurs privés et publics marocains et a donné lieu à un certain nombre de constats et de recommandations. Parmi les constats on relève une situation nutritionnelle souvent préoccupante, particulièrement en zone rurale ; une double dualité verticale et horizontale dans les filières provenant de la cohabitation entre un secteur moderne, aux normes européennes et intégré, et un secteur traditionnel, informel, fragile et atomisé ; une forte dépendance de marché vis-à-vis de l'Union européenne et la présence d'importantes liquidités dans le système financier national sans valorisation locale. Les recommandations mettent l'accent sur la nécessité de mettre en oeuvre une véritable politique agroalimentaire qui doit englober le volet agricole et celui de l'aménagement rural ; puis sur la mise en place de dispositifs privés de coordination des filières, notamment pour assurer la maîtrise de la qualité des produits et plus globalement la compétitivité des entreprises ; enfin sur la priorité à donner au dépassement des antagonismes commerciaux bilatéraux, par la construction d'une géostratégie agroalimentaire méditerranéenne.

International audience; Les critères de compétitivité internationale pour les entreprises agroalimentaires les poussent de plus en plus vers des investissements de mise à niveau des outils industriels suivant les normes internationales dont l'application est encouragée par les gouvernements. Cependant les investissements nécessaires sont onéreux. L'article s'interroge sur le fait que l'attribution d'allocation de ressources publiques aux entreprises d'export nuit au développement des entreprises locales, fournisseuses des ménages à bas revenus, et ne correspond donc pas tout à fait à la demande de la population nationale. La sécurité alimentaire des populations est menacée par trois aspects du fait de l'application des normes internationales. D'une part, parce que les ressources rares sont détournées par les entreprises exportatrices. D'autre part le prix élevé des produits alimentaires de qualité, répondant aux normes internationales, les rend inaccessibles à la majorité des consommateurs locaux. Enfin, la spécialisation des produits normalisables risque de conduire à une perte de la diversité alimentaire qui fait la spécificité de l'alimentation méditerranéenne.

Diffusion du document : INRA Unité Mixte de Recherche MOISA Marchés Organisations Institutions et Stratégies d'acteurs 2 place Viala 34060 Montpellier Cedex 1 (FRA); National audience; Cette note décrit le contexte et les enjeux géostratégiques, le cadrage macroéconomique et la demande socio-politique en terme de recherche dans le domaine agricole, agroalimentaire et rural en insistant sur la nécessité d'une nouvelle approche de la coopération, compte-tenu des faibles résultats de la conférence euro-méditerranéenn e de Barcelone. Quatre thématiques de recherche sont ensuite proposées : les sécurités alimentaires et les modèles de consommation, la compétitivité et la régulation des filières agroalimentaires, le cadre institutionnel et la gestion du développement rural durable, les politiques publiques agricoles, agroalimentaires et rurales.

National audience; Les dysfonctionnements observés dans le système alimentaire au cours de la période récente (vache folle, poulet à la dioxine, hormones, etc.) entraînent une crise de confiance de la part des consommateurs, qui s'ajoute aux tensions perceptibles dans les relations internationales (différends Europe/Etats-Unis). Ces "ruptures" induisent des modifications dans les stratégies des entreprises, une radicalisation dans la contestation des modèles techniques de production et de consommation. On observe en conséquence l'apparition de nouvelles "frontières" sur les marchés et au niveau des acteurs ainsi que de nouveaux modes de régulation. Ainsi la convergence des modèles de consommation alimentaire au plan international est tout à la fois cause et conséquence de l'apparition de "produits mondiaux", tandis que simultanément, la fragmentation des groupes sociaux conduit à une hyper segmentation des marchés. Enfin, on constate qu'au-delà de l'ajustement traditionnel par les prix se multiplient des normes et signalisations tant publiques (labels, Appellation d'origine contrôlée), que privées (marques et allégations commerciales), avec des investissements immatériels et des relations formelles et informelles, qui, combinées dans le cadre de nouveaux modes d'organisation, tendent à créer des opportunités de rentes pour les acteurs qui les mobilisent. Ces changements multiples auront des conséquences importantes sur la structuration et sur la dynamique des systèmes alimentaires de demain.

Egalement paru dans : Problèmes Economiques, 2719,2001/06/27, pp 23-29 Série "Progrès et agriculture" ; AG 24; National audience; En 1995, le commerce mondial de marchandises a franchi le seuil symbolique des 5 000 US. La croissance rapide du commerce international constitue l'une des manifestations du mouvement de mondialisation, mais elle est loin d'être la seule. Après un rappel des travaux les plus marquants qui ont conduit à l'émergence du concept de mondialisation, la première partie de cet article est consacrée à la mesure du phénomène de mondialisation de l'économie agroalimentaire sous toutes ses formes. La deuxième partie s'attache à la mise en évidence des facteurs principaux qui expliquent les évolutions observées et à l'identification des principaux acteurs qui en sont la cause.