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Le travail de l’enseignant chercheur tel qu’il existe aujourd’hui est tres fortement structure autour de la publication d’articles academiques dans des revues scientifiques. Ces dernieres sont en general pilotees par des comites de lecture qui organisent une evaluation des soumissions en double aveugle. S’il existe evidemment des variations et de constantes innovations, cette organisation du travail academique reste fortement institutionnalisee, et de plus en plus mondialisee. Nous proposons ici une archeologie de ces revues en identifiant les moments d’emergence de leurs principales caracteristiques, a savoir : les societes savantes et publications periodiques du 17e siecle, les politiques editoriales et comites de lecture du 18e, et enfin l’evaluation en double aveugle qui s’impose a la fin du 20e. Pour ce faire, une partie de nos analyses historiques se concentrent sur les deux periodiques consideres comme matrices des revues modernes : le Journal des Scavans francais et les Philosophical Transactions britanniques. Il s’agit ici de problematiser l’ensemble de ces caracteristiques en les replacant dans les contextes ou elles ont permis de repondre a des problemes, tout en faisant l’objet de debats et negociations. Cet article a pour but de contribuer a l’histoire de la pensee manageriale, mais egalement, dans son approche fortement influencee par la pensee foucaldienne, d’alimenter une critique (au sens philosophique) des sciences de gestion comme discipline et comme profession.

A detailed study of the microclimate of Petites Dales karst cave with single-entrance is presented in this paper. Two years of cave monitoring investigate temperature, weight of water vapour and airflow distributions outside and inside the cavity to determine the global behaviour of the karst cave. In addition, daily measurements of temperature and airflow demonstrate clearly the stratification of the air and inversions of the airflow during day-time. The cave air is intensively exchanged with external air during the years, with two main modes: (i) airflow enters from the ceiling during summer period and (ii) airflow enters from the floor during winter. At the entrance, an Sshaped velocity profile was observed and far from the entrance, convection loops were observed. During the other period of the year, the airflows may switch from top to bottom or conversely. The thermodynamic conditions of switching are discussed in this paper. This study provided for the first time evidence of daily airflow inversion. Study of cave climates is required in the comprehension of cave flora and fauna, thermodynamic conditions for karst processes underground, hydrogeological features of speleothems, human impact when caves are visited. Key words: cave, microclimate, karst, airflow, temperature, variability. Dnevni in sezonski obrati smeri zracnega toka v jami Petites Dales, Normandija, Francija V clanku porocamo o podrobni mikroklimatski studiji v jami Petites Dales. V jami z enim samim vhodom smo dve leti opazovali temperaturo, vlago in porazdelitev zracnih tokov. Podrobne dnevne meritve temperature in zracnega toka kažejo na stratifikacijo in dnevni obrat smeri toka. Poleti zunanji zrak vdira v jamo pri stropu, pozimi pa pri tleh. Pri tem se pri vhodu oblikuje profil hitrosti zraka v obliki crke S, globlje v jami pa konvekcijska zanka. V vmesnih obdobjih lahko pride do preklapljanja iz dotoka pod stropom v dotok pri dnu in obratno, kar v clanku obravnavamo z vidika termodinamike. V tej raziskavi smo prvic pojasnili dnevne obrate smeri zraka v primerljivih jamah. Studije jamske mikroklime so pomembne za razumevanje jamskega ekosistema, procesov v jamah ter clovekovega vpliva nanje. Kljucne besede: jama, mikroklima, kras, zracni tok, temperatura, spremenljivost.

Purpose – This study aims to investigate a declaration of the principles of the Société de Philosophie des Sciences de Gestion/Society for the Philosophy of Organisation sciences (SPSG). Organisation sciences still need to be questioned and rendered more complex, even mistreated, and the concepts they apply have yet to be clarified, mastered and organised to go beyond management ideologies that obscure the project to develop a genuine science, with pseudo-rationalisation replacing real thought. Design/methodology/approach – This task could be accorded to a philosophy of organisation sciences that should be understood as a “philosophy of science of organisation sciences”. Findings – The aim of such a philosophical programme is twofold: to expose the presuppositions and predispositions of organisation scholars and to analyse and clarify their scientific theories and concepts. Originality/value – The ambition of the SPSG is to contribute to the development of that philosophical programme.

International audience; BACKGROUND & AIMS:Colonic tissues of patients with inflammatory bowel disease have been reported to have increased proteolytic activity, but no studies have clearly addressed the role of the balance between proteases and antiproteases in the pathogenesis of colitis. We investigated the role of Elafin, a serine protease inhibitor expressed by skin and mucosal surfaces in human inflammatory conditions, and the proteases neutrophil elastase (NE) and proteinase-3 (PR-3) in mice with colitis.METHODS:We studied mice with heterozygous disruptions in NE and PR-3, mice that express human elafin (an inhibitor of NE and PR-3), and naïve mice that received intracolonic adenoviral vectors that express elafin. Trinitrobenzene sulfonic acid (TNBS) or dextran sodium sulphate (DSS) was used to induce colitis. Protease, cytokine levels, and NF-κB activity were measured in colons of mice. Caco-2 and HT29 cells were studied in assays for cytokine expression, permeability, and NF-κB activity.RESULTS:Elafin expression or delivery re-equilibrated the proteolytic balance in inflamed colons of mice. In mice given TNBS or DSS, transgenic expression of elafin or disruption of NE and PR-3 protected against the development of colitis. Similarly, adenoviral delivery of Elafin significantly inhibited inflammatory parameters. Elafin modulated a variety of inflammatory mediators in vitro and in vivo and strengthened intestinal epithelial barrier functions.CONCLUSIONS:The protease inhibitor Elafin prevents intestinal inflammation in mouse models of colitis and might be developed as a therapeutic agent for inflammatory bowel disease.

Afin de depasser certains problemes epistemologiques classiques, nous proposons une justification et une illustration du modele CDEPM de Magne (2009) du processus de creation de modeles en un cycle de 5 etapes de construction et d’evaluation de la connaissance (Comprendre, Decrire, Expliquer, Predire, Maitriser ou CDEPM). Il permet aux chercheurs et aux praticiens d’expliciter la ou les finalites de leurs modeles et donc d’en tester les proprietes, afin de les ameliorer, de les rendre plus robustes. Deux etudes de modeles classiques (Hawthorne et le neo-institutionnalisme sociologique) permettent d’illustrer sa logique et sa pertinence.

La Ville de Paris est alimentee a 10 % par des eaux karstiques captes dans la region de Verneuil-sur-Avre. La superficie du bassin versant represente 400 km 2 . Ces emergences karstiques presentent une saisonnalite sur les debits ainsi que sur les parametres nitrate et turbidite, qui peuvent depasser la limite de qualite de l'eau destinee a la consommation humaine. Le substratum geologique est forme par les sables du Perche, date du Cenomanien moyen-superieur. La geologie de la region est complexe, faillee en plus d'etre recouverte d'une epaisseur importante d'argile a silex et de formations d'alteration. Le nombre de betoires est tres important et de plusieurs types. Leur distribution est fonction de la geomorphologie et de la tectonique. Leur influence sur les Sources de la Vigne est saisonniere et variable, conduisant notamment a des pointes de turbidite. Une gestion rigoureuse de ces sources, ainsi qu'une surveillance. Pour repondre aux exigences de qualite fixees dans le Code de Sante publique, une usine permettant de traiter notamment la turbidite est en cours de construction pres de Paris Pour comprendre et connaitre le fonctionnement de cet aquifere, des prelevements pour l'analyse des parametres nitrates, conductivite, turbidite, sont realises mensuellement dans des puits et les cours d'eau du bassin versant. Nous remarquons une heterogeneite spatiale des concentrations en nitrates dans la nappe, vraisemblablement dues aux variations de facies geologiques. D'autre part une correlation entre les niveaux de la nappe et les concentrations en nitrates aux Sources de la Vigne a ete trouvee. Pour les nitrates, des actions preventives de grande ampleur ont ete lancees. Un partenariat avec l'Agence de l'Eau Seine Normandie, Eau de Paris, la Chambre d'Agriculture d'Eure-et-Loir et Raffin-Service et une Charte pour reduire les fuites de nitrates a ete proposee sur 4 500 ha. Les etudes hydrogeologiques ont permis de mieux selectionner les parcelles ou les actions devaient etre menees en priorite.

Endoplasmic reticulum (ER) stress is sensed by cells in different physiopathological conditions in which there is an accumulation of unfolded proteins in the ER. A coordinated adaptive program called the unfolded protein response is triggered and includes translation inhibition, transcriptional activation of a set of genes encoding mostly intracellular proteins, and ultimately apoptosis. Here we show that insulin-like growth factor (IGF)-binding protein-1 (IGFBP-1), a secreted protein that modulates IGF bioavailability and has other IGF-independent effects, is potently induced during ER stress in human hepatocytes. Various ER stress-inducing agents were able to increase IGFBP-1 mRNA levels, as well as cellular and secreted IGFBP-1 protein up to 20-fold. A distal regulatory region of the human IGFBP-1 gene (-6682/-6384) containing an activating transcription factor 4 (ATF4) composite site was required for promoter activation upon ER stress. Mutation of the ATF4 composite site led to the loss of IGFBP-1 regulation. Electrophoretic mobility shift assay revealed an ER stress-inducible complex that was displaced by an ATF4 antibody. Knockdown of ATF4 expression using two specific small interfering RNAs impaired up-regulation of IGFBP-1 mRNA, which highlights the relevance of ATF4 in endogenous IGFBP-1 gene induction. In addition to intracellular proteins involved in secretory and metabolic pathways, we conclude that ER stress induces the synthesis of secreted proteins. Increased secretion of IGFBP-1 during hepatic ER stress may thus constitute a signal to modulate cell growth and metabolism and induce a systemic adaptive response.

International audience; A mixture of nine microorganisms (six bacteria and three yeasts) from the microflora of surface-ripened cheeses were subjected to in vitro digestive stress in a three-compartment "dynamic gastrointestinal digester" (DIDGI). We studied the microorganisms (i) grown separately in culture medium only (ii) grown separately in culture medium and then mixed, (iii) grown separately in culture medium and then included in a rennet gel and (iv) grown together in smear-ripened cheese. The yeasts Geotrichum candidum, Kluyveromyces lactis and Debaryomyces hansenii, were strongly resistant to the whole DIDGI process (with a drop in viable cell counts of less than < 1 log CFU mL(-1)) and there were no significant differences between lab cultures and cheese-grown cultures. Ripening bacteria such as Hafnia alvei survived gastric stress less well when grown in cheese (with no viable cells after 90 min of exposure of the cheese matrix, compared with 6 CFU mL(-1) in lab cultures). The ability of Corynebacterium casei and Staphylococcus equorum to withstand digestive stress was similar for cheese and pure culture conditions. When grow in a cheese matrix, Brevibacterium aurantiacum and Arthrobacter arilaitensis were clearly more sensitive to the overall digestive process than when grown in pure cultures. Lactococcus lactis displayed poorer survival in gastric and duodenal compartments when it had been grown in cheese. In vivo experiments in BALB/c mice agreed with the DIDGI experiments and confirmed the latter's reliability.

Background & Aims Molecular mechanisms underlying alcoholic liver disease (ALD) are still not fully understood. Activating transcription factor-4 (ATF4) is the master coordinator of the integrated stress response (ISR), an adaptive pathway triggered by multiple stressors. which can promote cell death and induce metabolic dysregulation if the stress is intense or prolonged. The aim of this study was to assess the effect of alcohol on the ISR signaling pathway in human liver cells and to define the role of cytochrome P450 2E1 (CYP2E1) in this response. Methods Primary cultured human hepatocytes and human HepG2 cells over-expressing CYP2E1 by adenoviral infection were exposed to ethanol (25–100mM) for 8–48h. Results Ethanol treatment of both liver cells up-regulated ATF4 as well as the pro-survival and the pro-apoptotic transcriptional program of the ISR. Indeed, in CYP2E1-expressing HepG2 cells exposed to ethanol, the expression of ISR target genes ( HMOX-1, GCLC, AsnS, IGFBP-1, GADD34, CHOP, ATF3, CHAC1 ) was induced. Up-regulation of ATF4 and the ISR transcriptional program was decreased by addition of the anti-oxidant glutathione. Several mechanisms mediated ATF4 protein induction, including, at early times, the phosphorylation of eIF2α which controls ATF4 translation, and, at later times, increased mRNA level and increased stability of the protein. A decrease in cell survival was also observed. Conclusions This study demonstrates that both CYP2E1 and ethanol induce ATF4 and the integrated stress response, a pathway which coordinates signals from multiple stresses, as well as established risk factors for ALD, and can display detrimental cellular effects upon prolonged activation.

Ce document retranscrit les grandes lignes de trois des interventions suivies de tables rondes organisées lors de la première édition du International Forum on Industrial Safety, qui s’est tenu à Toulouse en 2008: (1) «Quel équilibre entre sécurité contrainte et sécurité gérée?», animée par René Amalberti; (2) «Introduction à l’incertitude», animée par Laurent Magne; (3) «Introduction aux notions de risque au travers d’un conte de fées», animée par Gilles Motet.

Using a volontarily restricted theoretical and empirical corpus focused on control, we aim at proposing a “technological approach” of management tools and organizations, so as to go further than traditional lacks in “Accounting, Control & Audit” and management sciences. We will show that they are composed of rich intricated parts: on the one hand a science of design and on the other hand a science of social processes., À l'aide d'un corpus théorique et empirique volontairement restreint et centré sur le contrôle, nous proposons une « approche technologique » des outils de gestion et des organisations, pour essayer de dépasser les lacunes classiques en CCA et sciences de gestion. Nous montrerons que cette approche riche comporte deux volets inextricablement liés : d'une part une science de la conception et d'autre part une science du social.

International audience; BACKGROUND/AIMS: Insulin-like growth factor-binding protein-1 (IGFBP-1) modulates cell growth and metabolism in a variety of physiopathological conditions. The aim of this study was to determine the molecular mechanisms involved in IGFBP-1 upregulation by ethanol. METHODS: We studied IGFBP-1 regulation by ethanol at the protein, mRNA and gene promoter levels in the human hepatocarcinoma cell line, HepG2, which does not express significantly ethanol-metabolizing enzymes. RESULTS: Ethanol (35-150mM) induced the IGFBP-1 mRNA and protein up to 5-fold in a dose-dependent manner. A similar effect was observed using primary cultures of human hepatocytes. Various inhibitors of ethanol metabolism and the antioxidant N-acetylcysteine did not prevent ethanol effects. While ethanol did not modify the IGFBP-1 gene promoter activity, it elicited a 2- to 3-fold increase in IGFBP-1 mRNA half-life and this stabilization required the 5' and the 3' untranslated mRNA region. Ethanol triggered a rapid activation of c-Jun N-terminal Kinase (JNK) in HepG2 cells and IGFBP-1 induction was significantly decreased by a specific inhibitor of JNK. CONCLUSIONS: This study reveals a novel pathway of gene regulation by alcohol which involves the activation of JNK and the consequent mRNA stabilization.

National audience