Killing the textbook softly: From commercial textbooks to student-centered curricula

This report retraces the 10-year evolution of a higher-educational French language program that went from using commercial textbooks to student-centered curricula through three main stages: from American commercial textbooks to French commercial textbooks, from commercial textbooks to OER) textbooks, and from OER textbooks to student-centered curricula. The gradual evolution illustrates a way to handle resistance to change through the progressive implementation of new research or practice-based methods: action-oriented methodology for the first stage, Second Language Acquisition research-based approaches for the second stage, and practices based on current pedagogical trends for the third stage. The report provides the pedagogical rationale for each transition, highlighting the discrepancy between the very concept of textbook and what current research and practice in foreign language pedagogy advocates and a first-hand experience of what it entails to break away from American commercial textbooks, commercial textbooks, and ultimately textbooks altogether

Republique et citoyennete a l'aube du second siecle. Une certaine idée de la république chez Pline le Jeune

De nombreux auteurs dont Th.Mommsen, E. Allain, C. E. Pulciano et F. Trisoglio et J. Gaudemet ont relevé l'esprit profondément humaniste qui animait Pline le Jeune et qui se traduit par ses donations, son aide et son soutien auprès de jeunes gens de sa cité de Côme mais aussi par son inquiétude d'une répression trop sévère à l'égard des chrétiens de Pont et Bithynie. Son souci à l'égard des esclaves et des affranchis témoigne également, chez ce disciple lointain de Cicéron (P. Dragicevic), d'un intérêt accru pour la “question sociale” et pour le développement en taille et en sagesse de la Cité. C'est ainsi que Pline envisage sous deux aspects qui paraissent profondément contradictoires un idéal dont l'idée démocratique n'est pas absente: non seulement les citoyens doivent être nombreux mais ils doivent jouir de la libertas, de la securitas et respecter un «état de droit» en ne bousculant pas les bonnes traditions acquises. Les membres de la Cité idéale de Pline participent certes à la grandeur de l'Urbs de par leurs activités et leur confiance en César mais n'ont pas à modifier le régime parfait et harmonieux que semble dorénavant incarner le Prince. Il n'y a donc plus de place pour la démagogie car «le nombre ne peut avoir raison du poids des sentences, de la justesse des votes... de la qualité des avis.» Dès lors, l'opinion de Pline est le reflet de la nouvelle mentalité «antonine» au début du Second siècle ; elle préfigure la conception latine généreuse mais réduite de la ciuitas du Bas-Empire.Numerosos autores de los cuales Th. Mommsen, E. A1llain, S. E. Pulciano, F. Trisolgio y J. Gaudemet han alzado el espiritù profondamento humanisme que anima Plinio le Joven y que se traduce por sus donaciones su ayuda y su sosten hacia juvenes de su ciudad de Como pero tambien por su proccupacion de una represion demasiada dura hacia los Cristianos de Ponto y Bitinia. Su cuidado en consideracion a los esclavos y los emancipados testiga de la misma manera por este lejano discipulo de Tullius Cicero (Padre Dragicevic) de un interes mas importante por la cuestion sociale y por el desarrollamiento en estatura e en sabiduria de la ciudad. Asi es que Plinio ve dos aspectos que aparecen profundamente contradictorios un ideal cuya idea democratica n o es ausente : non solo los ciudadanos no deben estar numerosos pero deben gozar de la libertas de la securitas y respectar un «estado de derecho» sin trastonar las buenas tradiciones recibidas . Los membros de la ciudad ideal de Plinio participan desde luego al prestigio del Urbs con sus actividades y su confianza en Caesar pero no han que cambiar el regimen perfecto e armonioso que parece desde ahora encarnar el Principe. No hay desde luego sitio por la demagogia: pues, «el nombre no puede tener razon del peso de las semillas, de la rectidud de los votos… de la calidad de los avisos. » Asi, la opinion de Plinio es el reflecto de la nueva mentalidad «antoniana» al principio del segundo siglo ; prefigura la concepcion latina generosa pero recta de la ciudad del Bajo Empiro

Evidence for short-range antiferromagnetic fluctuations in Kondo-insulating YbB12

The spin dynamics of mixed-valence YbB12 has been studied by inelastic neutron scattering on a high-quality single crystal. In the Kondo-insulating regime realized at low temperature, the spectra exhibit a spin-gap structure with two sharp, dispersive, in-gap excitations at E = 14.5 and approximately 20 meV. The lower mode is shown to be associated with short-range correlations near the antiferromagnetic wave vector q0 = (1/2, 1/2, 1/2). Its properties are in overall agreement with those expected for a "spin exciton'' branch in an indirect hybridization gap semiconductor.Comment: 4 pages, 4 figures ; submitted to Physical Review Letter

Non Magnetic Impurities in the Spin-Gap Phase of the Cuprate

It is now well established that Zn doping of high-$T_C$ cuprates reduces their $T_C$ and triggers the appearence of a spin glass phase. In this context, we have solved exactly the problem of N non magnetic impurities in the staggered flux phase of the Heisenberg model which we assume to be a good mean-field approximation for the spin-gap phase of the cuprates. In this model, the quasiparticule spectrum has four nodes on the Fermi surface, and linearization of the spectrum in the neighbourhood of these nodes leads to a system of 2D Dirac fermions. In the presence of a macroscopic number of (non magnetic) impurities, the problem has a characteristic logarithmic structure that renders ineffective the usual perturbative expansions. We have used this logarithmic structure to calculate an exact solution. For a concentration ni of impurities in the unitary scattering limit, the additional density of states is found to be proportional to $ni/(w \ln^2 (|w|/D))$ (where D is the infrared cut-off of the linearized spectrum) in analogy with the 1D case of doped spin-Peierls and two-leg ladders compounds. We argue that the system exhibits a quasi long-range order at T=0 with instantaneous spin-spin correlations decreasing as $ni/ \ln^4 (ni/R_{ij})$ for large distances $R_{ij}$ between impurity sites. We predict enhanced low energy fluctuations and compare these results to NMR and inelastic neutron scattering experiments in the high-$T_C$ cuprates.Comment: proceeding of SCES98 conference in Paris, July '9

Spontaneous deformation of the Fermi surface due to strong correlation in the two-dimensional t-J model

Fermi surface of the two-dimensional t-J model is studied using the variational Monte Carlo method. We study the Gutzwiller projected d-wave superconducting state with an additional variational parameter t'_v corresponding to the next-nearest neighbor hopping term. It is found that the finite t'_v<0 gives the lowest variational energy in the wide range of hole-doping rates. The obtained momentum distribution function shows that the Fermi surface deforms spontaneously. It is also shown that the van Hove singularity is always located very close to the Fermi energy. Using the Gutzwiller approximation, we show that this spontaneous deformation is due to the Gutzwiller projection operator or the strong correlation.Comment: 4 pages, 3 eps figures, revte