Dialogues with the absent other: using reported speech and the vocabulary of citizenship for contesting ecological laws and institutions

This article examines how a professional group articulates views of the new laws and institutions that call them to accept new practices and new meaning in the name of the ecological common good. Drawing on a framework integrating the approach of social representations and rhetorical social psychology with legal institutionalism, we analyze in-depth interviews and focus groups (n = 29) with artisanal fishers. We explore how fishers use reported speech, that is, the quotation of others or self in own discourse, for building representations of Self, institutional-Others and their relations, examining also the values and dimensions of citizenship they mobilize with it. We show how fishers consistently use reported speech for presenting a negative institutional-Other acting in disrespect of the civil and political dimensions of citizenship, and a positive Self acting as a competent citizen – although rarely as a good ecological citizen. We discuss how focusing on reported speech by drawing on a theorization of how the institutional dimension interacts with the micro-level of interaction and discourse extends current comprehension of how contestation of the new meaning embedded in new laws can be warranted and maintained.info:eu-repo/semantics/acceptedVersio

Past-present discontinuity in ecological change and marine governance: an integrated narrative approach to artisanal fishing

Today artisanal fishers working in Natura 2000 coastal protected sites face two major types of change: in marine resources, and the governance of their professions. Such transformations affect fishers’ livelihoods, identities and traditions, yet little is known about how these professionals elaborate on these changes – i.e., as continuities or discontinuities - in the narratives they produce as a group. Interviews and focus-groups with artisanal fishers and shellfish harvesters (n=36) from the Portuguese Southwest coast were subjected to a two-step analysis. First, a textual analysis with Iramuteq helped select the themes directly related to marine resources and governance. Second, three main narratives - on algae, barnacles and fish - were reconstructed. These were then explored regarding: (1) narrative formats (stability, regressive, progressive, mixed); (2) whether/how these formats elaborated changes as continuities or discontinuities; (3) the roles attributed to Self and Others, and whether and how these legitimized the laws, opening avenues for change; and (4) whether narratives were unified or fragmented. This study illustrates how transformations are presented through various combinations of narrative formats, sometimes mobilized to resist and other times to legitimate legal institutional change. It shows how institutional change can be integrated into local narratives as a positive contribution through a process that implies re-constructing the collective identity and local traditions. Through a narrative approach, this paper offers an integrated examination of fishers’ concerns towards their professions and the laws regulating them, and provides useful insight into how and when marine governance is more/less likely to be legitimized.info:eu-repo/semantics/acceptedVersio

Magnetic exchange mechanism for electronic gap opening in graphene

We show within a local self-consistent mean-field treatment that a random distribution of magnetic adatoms can open a robust gap in the electronic spectrum of graphene. The electronic gap results from the interplay between the nature of the graphene sublattice structure and the exchange interaction between adatoms.The size of the gap depends on the strength of the exchange interaction between carriers and localized spins and can be controlled by both temperature and external magnetic field. Furthermore, we show that an external magnetic field creates an imbalance of spin-up and spin-down carriers at the Fermi level, making doped graphene suitable for spin injection and other spintronic applications.Comment: 5 pages, 5 figure

Phenomenological study of the electronic transport coefficients of graphene

Using a semi-classical approach and input from experiments on the conductivity of graphene, we determine the electronic density dependence of the electronic transport coefficients -- conductivity, thermal conductivity and thermopower -- of doped graphene. Also the electronic density dependence of the optical conductivity is obtained. Finally we show that the classical Hall effect (low field) in graphene has the same form as for the independent electron case, characterized by a parabolic dispersion, as long as the relaxation time is proportional to the momentum.Comment: 4 pages, 1 figur

Hole concentration in a diluted ferromagnetic semiconductor

We consider a mean-field approach to the hole-mediated ferromagnetism in III-V Mn-based semiconductor compounds to discuss the dependence of the hole density on that of Mn sites in Ga_{1-x}Mn_xAs. The hole concentration, p, as a function of the fraction of Mn sites, x, is parametrized in terms of the product m*J_{pd}^2 (where m* is the hole effective mass and J_{pd} is the Kondo-like hole/local-moment coupling), and the critical temperature Tc. By using experimental data for these quantities, we have established the dependence of the hole concentration with x, which can be associated with the occurrence of a reentrant metal-insulator transition taking place in the hole gas. We also calculate the dependence of the Mn magnetization with x, for different temperatures (T), and found that as T increases, the width of the composition-dependent magnetization decreases drammatically, and that the magnetization maxima also decreases, indicating the need for quality-control of Mn-doping composition in diluted magnetic semiconductor devices.Comment: 4 pages, 3 figures, RevTeX 3; Fig. 1 changed, new references adde

A tool to analyze robust stability for constrained nonlinear MPC

A sufficient condition for robust asymptotic stability of nonlinear constrained model predictive control (MPC) is derived with respect to plant/model mismatch. This work is an extension of a previous study on the unconstrained nonlinear MPC problem, and is based on nonlinear programming sensitivity concepts. It addresses the discrete time state feedback problem with all states measured. A strategy to estimate bounds on the plant/model mismatch is proposed that can be used off-line as a tool to assess the extent of model mismatch that can be tolerated to guarantee robust stability.http://www.sciencedirect.com/science/article/B6V4N-4R7F42T-2/1/7729956156701c2970c6a488f929884

Electron waves in chemically substituted graphene

We present exact analytical and numerical results for the electronic spectra and the Friedel oscillations around a substitutional impurity atom in a graphene lattice. A chemical dopant in graphene introduces changes in the on-site potential as well as in the hopping amplitude. We employ a T-matrix formalism and find that disorder in the hopping introduces additional interference terms around the impurity that can be understood in terms of bound, semi-bound, and unbound processes for the Dirac electrons. These interference effects can be detected by scanning tunneling microscopy.Comment: 4 pages, 7 figure