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Le point de départ de cette recherche est l'étude d'un dossier de corruption politique (Ville d'Anjou, Québec) et du procès qui l'a suivi. Sur cette base, l'auteur met l'accent sur la mise en forme (formalisation) pénale, c'est-à-dire le passage du fait social au fait juridique et judiciaire.
Deux moments décisifs sont retenus : celui de l'enquête et celui des poursuites judiciaires. Ce sont elles qui effectuent les opérations essentielles de reconstitution, interprétation et codage juridique des faits. De plus, chacune de ces opérations s"effectue en anticipant sur les opérations ultérieures afin d'assurer la recevabilité finale du produit.

PurposeThere are several studies about the adoption of e-commerce for small-to-medium enterprises (SMEs) that separately, and in a dispersed manner, examine different theoretical approaches. The purpose of this paper is to unify a set of variables to form an integrated model of measurement of the adoption of e-commerce for SMEs.Design/methodology/discussionBased on an extensive review of empirical studies focused on the adoption of e-commerce in SMEs, a grouped and integrated model of e-commerce among SMEs was constructed. It was built upon the methodology of psychometrics and was subsequently statistically tested for reliability and validity. A broad study has not been carried out. Thus, the small sample size does not allow the estimation of this model's predictability.FindingsThis paper proposes a final model, comprising 14 variables (82 items), grouping the significant effects of e-commerce adoption.Originality/valueThis tool is feasible, offering an initial model enabling detailed examination of variables affecting the adoption of e-commerce in SMEs. It contributes significantly to the development of this line of research.

We consider spin relaxation of finite-size spin chains exchanged coupled with a one-dimensional (1D) electron gas at the edge of a quantum spin Hall (QSH) insulator. Spin lifetimes can be enhanced due to two independent mechanisms. First, the suppression of spin-flip forward scattering inherent in the spin momentum locking of the QSH edges. Second, the reduction of spin-flip backward scattering due to destructive interference of the quasiparticle exchange, modulated by k F d, where d is the inter-spin distance and k F is the Fermi wavenumber of the electron gas. We show that the spin lifetime of the S = 1/2 ground state of odd-numbered chains of antiferromagnetically coupled S = 1/2 spins can be increased more than 4 orders of magnitude by properly tuning the product k F d and the spin size N, in strong contrast with the 1D case. Possible physical realizations together with some potential issues are also discussed. ; JFR acknowledges financial support by FCT- The Portuguese Foundation for Science and Technology, under the project 'PTDC/FIS-NAN/4662/2014' (016656), MINECO-Spain (Grant No. MAT2016-78625-C2) and Generalitat Valenciana Prometeo2017/139. FD acknowledges financial support from Spanish Government through grants MAT2015-66888-C3-2-R, Basque Government, grant IT986-16 and Canary Islands program Viera y Clavijo (Ref. 2017/0000231). FD acknowledges the hospitality of the Departamento de Física Aplicada of the Universidad de Alicante.

Exchange interactions with itinerant electrons are known to act as a relaxation mechanism for individual local spins. The same exchange interactions induce the so-called RKKY indirect exchange interaction between two otherwise decoupled local spins. Here, we show that both the spin relaxation and the RKKY coupling can be seen as the dissipative and reactive response to the coupling of the local spins with the itinerant electrons. We thereby predict that the spin relaxation rates of magnetic nanostructures of exchanged coupled local spins, such as nanoengineered spin chains, have an oscillatory dependence on kFd, where kF is the Fermi wave number and d is the interspin distance, very much like the celebrated oscillations in the RKKY interaction. We demonstrate that both T1 and T2 can be enhanced or suppressed, compared to the single-spin limit, depending on the interplay between the Fermi surface and the nanostructure geometrical arrangement. Our results open a route to engineer spin relaxation and decoherence in atomically designed spin structures. ; J.F.R. acknowledges financial supported by MEC-Spain (Grant No. FIS2013-47328-C2-2-P) and Generalitat Valenciana (Grant No. ACOMP/2010/070), Prometeo. This work is funded by ERDF funds through the Portuguese Operational Program for Competitiveness and InternationalizationÐ COMPETE 2020, and National Funds through FCT-The Portuguese Foundation for Science and Technology, under the project PTDC/FIS-NAN/4662/2014 (Project.No. 016656). F.D. acknowledges support from Spanish Government through Grant No.MAT2015-66888-C3-2-R and Basque Government, Grant No. IT986-16.

El presente artículo analiza los aspectos jurídicos – institucionales de la cooperación internacional universitaria con el objetivo de presentar las modalidades que puede asumir en el entorno iberoamericano, desde el análisis del caso argentino. La metodología aplicada fue el análisis sistemático de documentos normativos nacionales y recomendaciones de organismos internacionales. Los resultados principales destacan la centralidad del rol del Estado en la promoción de entornos específicos de cooperación universitaria. Asimismo, se observa que las modalidades de cooperación internacional universitaria se corresponden con las funciones universitarias de docencia, investigación y extensión.

A method to calculate the effective spin Hamiltonian for a transition metal impurity in a non-magnetic insulating host is presented and applied to the paradigmatic case of Fe in MgO. In the first step we calculate the electronic structure employing standard density functional theory (DFT), based on generalized gradient approximation (GGA), using plane waves as a basis set. The corresponding basis of atomic-like maximally localized Wannier functions is derived and used to represent the DFT Hamiltonian, resulting in a tight-binding model for the atomic orbitals of the magnetic impurity. The third step is to solve, by exact numerical diagonalization, the N electron problem in the open shell of the magnetic atom, including both effects of spin–orbit and Coulomb repulsion. Finally, the low energy sector of this multi-electron Hamiltonian is mapped into effective spin models that, in addition to the spin matrices S, can also include the orbital angular momentum L when appropriate. We successfully apply the method to Fe in MgO, considering both the undistorted and Jahn–Teller (JT) distorted cases. Implications for the influence of Fe impurities on the performance of magnetic tunnel junctions based on MgO are discussed. ; AF acknowledges funding from the European Union's Seventh Framework Programme for research, technological development and demonstration, under the PEOPLE programme, Marie Curie COFUND Actions, grant agreement number 600375 and CONICET. JFR acknowledges financial support by Generalitat Valenciana (ACOMP/2010/070), Prometeo, and MEC-Spain (FIS2013-47328-C2-2-P).

Spin chains are among the simplest physical systems in which electron-electron interactions induce novel states of matter. Here we propose to combine atomic scale engineering and spectroscopic capabilities of state of the art scanning tunnel microscopy to probe the fractionalized edge states of individual atomic scale S=1 spin chains. These edge states arise from the topological order of the ground state in the Haldane phase. We also show that the Haldane gap and the spin-spin correlation length can be measured with the same technique. ; This work has been financially supported by MEC-Spain (Grants No. FIS2010-21883-C02-01, No. FIS2009-08744, and No. CONSOLIDER CSD2007-0010), European Union as well as Generalitat Valenciana, Grant No. Prometeo 2012-11. This work was carried out under the auspices of the NNSA of the U.S. DOE at LANL under Contract No. DE-AC52-06NA25396, and was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. This Letter is based upon work supported in part by the NSF under Grant No. PHY-1066293 and the hospitality of the Aspen Center for Physics.

We consider two intrinsic sources of noise in ultra-sensitive magnetic field sensors based on MgO magnetic tunnel junctions, coming both from 25 Mg nuclear spins (I = 5/2, 10% natural abundance) and S = 1 Mg-vacancies. While nuclear spins induce noise peaked in the MHz frequency range, the vacancies noise peaks in the GHz range. We find that the nuclear noise in submicron devices has a similar magnitude than the 1/f noise, while the vacancy-induced noise dominates in the GHz range. Interestingly, the noise spectrum under a finite magnetic field gradient may provide spatial information about the spins in the MgO layer. ; This work has been financially supported by MEC-Spain (Grant Nos. FIS2010-21883-C02-01, FIS2009-08744, European Union, and CONSOLIDER CSD2007-0010) as well as Generalitat Valenciana, Grant Prometeo 2012-11.

Multiple object video object segmentation is a challenging task, specially for the zero-shot case, when no object mask is given at the initial frame and the model has to find the objects to be segmented along the sequence. In our work, we propose a Recurrent network for multiple object Video Object Segmentation (RVOS) that is fully end-to-end trainable. Our model incorporates recurrence on two different domains: (i) the spatial, which allows to discover the different object instances within a frame, and (ii) the temporal, which allows to keep the coherence of the segmented objects along time. We train RVOS for zero-shot video object segmentation and are the first ones to report quantitative results for DAVIS-2017 and YouTube-VOS benchmarks. Further, we adapt RVOS for one-shot video object segmentation by using the masks obtained in previous time steps as inputs to be processed by the recurrent module. Our model reaches comparable results to state-of-the-art techniques in YouTube-VOS benchmark and outperforms all previous video object segmentation methods not using online learning in the DAVIS-2017 benchmark. Moreover, our model achieves faster inference runtimes than previous methods, reaching 44ms/frame on a P100 GPU. ; This research was supported by the Spanish Ministry ofEconomy and Competitiveness and the European RegionalDevelopment Fund (TIN2015-66951-C2-2-R, TIN2015-65316-P & TEC2016-75976-R), the BSC-CNS SeveroOchoa SEV-2015-0493 and LaCaixa-Severo Ochoa Inter-national Doctoral Fellowship programs, the 2017 SGR 1414and the Industrial Doctorates 2017-DI-064 & 2017-DI-028from the Government of Catalonia ; Peer Reviewed ; Postprint (published version)