Anthropogenic carbon in the eastern South Pacific Ocean

International audienceWe present results from the BIOSOPE cruise in the eastern South Pacific Ocean. In particular, we present estimates of the anthropogenic carbon CantTrOCA distribution in this area using the TrOCA method recently developed by Touratier and Goyet (2004a, b) and Touratier et al. (2007). We study the distribution of this anthropogenic carbon taking into account of the hydrodynamic characteristics of this region. We then compare these results with earlier estimates in nearby areas of the anthropogenic carbon as well as other anthropogenic tracer (CFC-11). The highest concentrations of CantTrOCA are located around 13° S 132° W and 32° S 91° W, and their concentrations are larger than 80 µmol kg-1 and 70 µmol kg-1, respectively. The lowest concentrations were observed below 800 m depths (=2 µ mol kg-1) and at the Oxygen Minimum Zones (OMZ), mainly around 140° W (-1). The comparison with earlier work in nearby areas provides a general trend and indicates that the results presented here are in general agreement with previous knowledge. This work further improves our understanding on the penetration of anthropogenic carbon in the eastern Pacific Ocean

Situation du criquet marocain "Dociostaurus maroccanusThunb., 1815" par rapport aux différentes espèces acridiennes : morphométrie et capacités de déplacements

La faculté de déplacements par vol des criquets adultes permet aux populations acridiennes de se déplacer sur de grandes distances et de rechercher des habitats dont les caractéristiques répondent le mieux à leurs besoins. Dans le présent travail, nous étudions des traits morphologiques d’un certain nombre d’espèces migratrices et non migratrices de deux sous-familles d’Acrididae (Oedipodinae et Gomphocerinae). Par les mesures de différentes parties du corps des criquets adultes, nous avons pu situer le criquet marocain "Dociostaurus maroccanus Thunb., 1815" par rapport à l’ensemble des espèces étudiées. Cette étude morphométrique, souligne bien la liaison existante entre les capacités des déplacements des criquets et leurs traits morphologiques. Ainsi, on note bien une importante distinction morphologique entre l’espèce migratrice Locusta migratoria et les espèces non migratrices. Dociostaurus maroccanus se montre capable d’effectuer des déplacements importants, mais elle ne peut être migratrice comme Locusta migratoria.Mots-clés : Morphométrie, capacités de déplacements, traits morphologiques, Criquet marocain, espèces migratrices

Ecology and biogeochemistry of contrasting trophic environments in the South East Pacific by carbon isotope ratios on lipid biomarkers

International audienceThe distribution of lipid biomarkers and their carbon isotope composition was investigated on suspended particles from different contrasting trophic environments at six sites in the South East Pacific. High algal biomass with diatom-related lipids was characteristic in the upwelling zone, whereas haptophyte lipids were proportionally most abundant in the nutrient-poor settings of the centre of the South Pacific Gyre and on its easter edge. Dinoflagellate–sterols were minor contributors in all of the studied area and cyanobacteria-hydrocarbons were at maximum in the high nutrient low chlorophyll regime of the subequatorial waters at near the Marquesas archipelago. The taxonomic and spatial variability of the relationships between carbon photosynthetic fractionation and environmental conditions for four specific algal taxa (diatoms, haptophytes, dinoflagellates and cyanobacteria) was also investigated. The carbon isotope fractionation factor (ep) of the diatom marker varied over a range of 16‰ along the different trophic systems. In contrast, ep of dinoflagellate, cyanobacteria and alkenone markers varied only by 7–10‰. The low fractionation factors and small variations between the different phytoplankton markers measured in the upwelling area likely reveals uniformly high specific growth rates within the four phytoplankton taxa, and/or that transport of inorganic carbon into phytoplankton cells may not only occur by diffusion but by other carbon concentrating mechanisms (CCM). In contrast, in the oligotrophic zone, i.e. gyre and eastgyre, relatively high ep values, especially for the diatom marker, indicate diffusive CO2 uptake by the eukaryotic phytoplankton. At these nutrient-poor sites, the lowest ep values for haptophytes, dinoflagellates and cyanobacteria infer higher growth rates compared to diatoms

A coherent picture of water at extreme negative pressure.

International audienceLiquid water at atmospheric pressure can be supercooled to 41 C (ref. 1) and superheated to C302 C (ref. 2). Experiments involving fluid inclusions of water in quartz suggest that water is capable of sustaining pressures as low as 140 MPa before it breaks by cavitation3. Other techniques, for which cavitation occurs consistently at around 30MPa (ref. 4), produce results that cast doubt on this claim. Here we reproduce the fluid-inclusion experiment, performing repeated measurements on a single sample--a method used in meteorology5, bioprotection6 and protein crystallization7, but not yet in liquid water under large mechanical tension. The resulting cavitation statistics are characteristic of a thermally activated process, and both the free energy and the volume of the critical bubble are well described by classical nucleation theory when the surface tension is reduced by less than 10%, consistent with homogeneous cavitation. The line of density maxima of water at negative pressure is found to reach 922:8 kgm3 at around 300 K, which further constrains its contested phase diagram

Normalized equilibrium in Tullock rent seeking game

International audienceGames with Common Coupled Constraints represent manyreal life situations. In these games, if one player fails tosatisfy its constraints common to other players, then theother players are also penalised. Therefore these games canbe viewed as being cooperative in goals related to meetingthe common constraints, and non cooperative in terms ofthe utilities. We study in this paper the Tullock rent seekinggame with additional common coupled constraints. We havesucceded in showing that the utilities satisfy the property ofdiagonal strict concavity (DSC), which can be viewed asan extention of concavity to a game setting. It not onlyguarantees the uniqueness of the Nash equilibrium but also of the normalized equilibrium

An agility reference model for the manufacturing enterprise : the example of the furniture industry

its drivers and capabilities, and even suggesting methodologies to develop agility. However, most of these efforts remain vague with respect to the characteristics and the expected contributions of the technologies involved or required. This paper proposes an agility reference model; a unifying conceptual representation of agility in terms of the necessary capabilities needed by every process involved in the enterprise seeking for agility. Agility is described using three capabilities which are believed to be the sources of competitive advantages; flexibility, responsiveness, and autonomy. It is shown that each capability addresses some specific issues and can only be thoroughly developed if the technologies used are characterized with some specific attributes or properties. The idea behind the proposed agility reference model was to derive a typology framework that emphasizes the taxonomy of the market interaction strategies for furniture products, and the competitive priorities that should be targeted by furniture enterprises aiming to be agile. Accordingly, the issues related to the different agility capabilities were discussed in the context of the furniture enterprise of the future. Then, the suitability of the proposed model for the derivation of the typology was explored based on case studies on two furniture manufacturing enterprises. The case studies analyze the context in terms of competitive priorities and customization strategies and investigate the agility properties of the technologies in use

An agility reference model for the furniture enterprise of the future

There is an extensive amount of research literature about the concept of agility, describing its drivers and capabilities, and even suggesting methodologies to develop agility. However, most of these efforts remain vague with respect to the characteristics and the expected contributions of the technologies involved or required. This paper proposes an agility reference model; a unifying conceptual representation of agility in terms of the necessary capabilities needed by every process involved in the enterprise seeking for agility. Agility is described using three capabilities which are believed to be the sources of competitive advantages; flexibility, responsiveness, and autonomy. It is shown that each capability addresses some specific issues and can only be thoroughly developed if the technologies used are characterized with some specific attributes or properties. The idea behind the proposed agility reference model was to derive a typology framework that emphasizes the taxonomy of the market interaction strategies for furniture products, and the competitive priorities that should be targeted by furniture enterprises aiming to be agile. Accordingly, the issues related to the different agility capabilities were discussed in the context of the furniture enterprise of the future. Then, the suitability of the proposed model for the derivation of the typology was explored based on case studies on two furniture manufacturing enterprises. The case studies analyze the context in terms of competitive priorities and customization strategies and investigate the agility properties of the technologies in use

Exploratory case studies on manufacturing agility in the furniture industry

Purpose – The purpose of this paper is to investigate the agility of advanced manufacturing technologies (AMTs) in furniture enterprises, and explores the appropriateness of a typology framework that correlates the technology infrastructure of the enterprise with its manufacturing strategy. Design/methodology/approach – This paper uses a clear and rigorous case study design and protocol. Empirical data are collected using structured surveys of two strategically selected furniture enterprises. The collected data are used to analyze the fit between the technology infrastructure of the enterprise and its strategic goals, and how this fit correlates with the theoretical categories stated by the typology. Findings – The case studies suggest that enterprise performance could be maximized if the competitive priorities and the customization strategy put in practice are in conformity with the available technology. Research limitations/implications – The findings of the case studies corroborate the all inclusive hypothesis suggested by the typology. The lack of triangulation of multiple data sources for more confidence about the results or the typology framework itself remains a limitation in this study. The two cases were representative to a certain extent of two out of the three theoretical ideal types stated by the typology. Practical implications – The explored typology can serve as a supporting tool for managers when making strategic investment decisions in their pursuit of a mass customization strategy within a specific market. Originality/value – The originality comes from the way the properties that should be displayed by the technologies used in furniture manufacturing enterprises to develop agility are drawn together

The Role of organizational competences in the evolution of business models

This paper presents the use of a conceptual framework designed for the management of organizational competences to contribute to the evolution of the business model of an enterprise. The framework, developed based on a detailed review of the history of the car manufacturer Toyota, was used for a Delphi study and an action-research applied in the furniture industry. The results suggest that it is applicable for ex-post analysis of organizational changes, as well as a strategy planning tool

Setting up an integrated plant of solid wood panels supplying the furniture enterprise of the future : an exploratory analysis

This paper explores conceptually the overall implications, impacts and benefits resulting from setting up an integrated factory for the production of large and standardized solid wood panels as the prime raw material used by a highly automated solid wood furniture plant. The paper begins with an overview of the current value creation network of solid wood furniture from the forest to the customer. Then, a comprehensive assessment of potential opportunities for improvement leading to higher enterprise agility is conducted. The advanced technologies that can be introduced in the crucial processes are also reviewed. The expected gains in terms of agility are identified, and different hypothetical scenarios are discussed