First critical field measurements of superconducting films by third harmonic analysis

The temperature behaviour of the first critical field ($B_{C1}$) of superconducting thin film samples can be determined with high accuracy using an inductive and contactless method. Driving a sinusoidal current in a single coil placed in front of the sample, a non zero third harmonic voltage $V_{3}$ is induced in it when Abrikosov vortices enter the sample. Conditions to be satisfied for the quantitative evaluation of $B_{C1}$ using this technique are detailed. As validation test, different type II superconductors (Nb, NbN, MgB$_{2}$ and Y$_{1}$Ba$_{2}$Cu$_{3}$O$_{7-d}$ under the form of thin films) have been measured. The comparison between experimental results, data presented in literature and theoretical predictions is presented and discussed.Comment: to be published in Journal of Applied Physic

In-situ measurement of the permittivity of helium using microwave NbN resonators

By measuring the electrical transport properties of superconducting NbN quarter-wave resonators in direct contact with a helium bath, we have demonstrated a high-speed and spatially sensitive sensor for the permittivity of helium. In our implementation a $\sim10^{-3}$ mm$^3$ sensing volume is measured with a bandwidth of 300 kHz in the temperature range 1.8 to 8.8 K. The minimum detectable change of the permittivity of helium is calculated to be $\sim6\times$$10^{-11}$ $\epsilon_0$/Hz$^{1/2}$ with a sensitivity of order $10^{-13}$ $\epsilon_0$/Hz$^{1/2}$ easily achievable. Potential applications include operation as a fast, localized helium thermometer and as a transducer in superfluid hydrodynamic experiments.Comment: 4 pages, 3 figure

Granularity-induced gapless superconductivity in NbN films: evidence of thermal phase fluctuations

Using a single coil mutual inductance technique, we measure the low temperature dependence of the magnetic penetration depth in superconducting NbN films prepared with similar critical temperatures around 16 K but with different microstructures. Only (100) epitaxial and weakly granular (100) textured films display the characteristic exponential dependence of conventional BCS s-wave superconductors. More granular (111) textured films exhibit a linear dependence, indicating a gapless state in spite of the s-wave gap. This result is quantitatively explained by a model of thermal phase fluctuations favored by the granular structure.Comment: 10 pages, 4 figures, to appear in Phys. Rev.

Age influences the effects of nicotine and monoamine oxidase inhibition on mood-related behaviors in rats

Epidemiological studies have demonstrated a comorbidity of smoking with depression and anxiety, particularly during adolescence. However, few animal studies have considered possible synergistic interactions between nicotine and other tobacco smoke constituents, such as monoamine oxidase (MAO) inhibitors, in the regulation of mood. The aim of the study was to test the hypothesis that nicotine combined with the irreversible MAO inhibitor, tranylcypromine, will differentially affect depression- and anxiety-related behaviors in adolescent and adult rats. Nicotine (0, 0.05, 0.2 mg/kg, s.c.) and tranylcypromine (3 mg/kg, i.p.) were tested separately, or together, on male rats aged postnatal days 30 and 68, in three mood-related behavioral tests: forced swim test (FST), elevated plus maze (EPM), and open field. Nicotine (0.2 mg/kg) in adults significantly decreased floating time in the FST and increased time spent in the open arm of the EPM, with no change in locomotor activity. Tranylcypromine pretreatment combined with nicotine (0.2 mg/kg) significantly increased locomotor activity and time spent in the center of the open field. Whereas nicotine alone had no significant effect on adolescents, it significantly increased locomotor activity and decreased floating time in the FST when combined with tranylcypromine pretreatment. There is an age-dependent effect of nicotine, alone and in combination with MAO inhibition, on mood-related behaviors. Whereas nicotine alone induces mood improvement in adults, it has no effect on adolescents. Nicotine combined with tranylcypromine has unique, age-dependent effects. Thus, experimental studies of smoking should consider both age and other tobacco constituents, such as MAO inhibitors, as critical factors

Les étonnements d'un vieux pédagogue

Tenir compte de l'inattention, de la distraction, de la diversité des intérêts des élèves devant les sujets qui leur sont proposés en classe, c'est faire preuve de réalisme et de conscience (professionnelle). Fonder une pédagogie sur l'oubli - jamais complet - et différent selon chacun, des formes linguistiques pratiquées entre tous les élèves peut paraître une gageure, un paradoxe. La longue et multiple expérience (multipliée par celle de tous les collègues qui pratiquent la méthode) de Jean Villegier permet d'assurer l'efficacité de 1'"Expression Libre".El pedagogo debe contar con la cantidad de olvido que acompaña, en el aprendizaje del alumno, cada una de sus lecciones. Los "mejores" alumnos se preparan para obtener, cierto día, una buena calificación . Y después se olvidan las asignaturas aprendidas... La mayoria de los metodos pedagógicos, y especi almente en la didáctica de los idiomas extranjeros, en consecuencia , reducen a lo mínimo la cantidad linguística que cada uno - y que todos - debe recordar... para "recitarla"... cuando sea. Al contrario, en la práctica de la libertad de expresión entre los alumnos, el profesor no vacila en ofrecer a todo el grupo, a medida que, se présenta la necesitad emplearlas, todas las expijesiones más variadas : por mas difíciles que parezcan a los gramáticos. Este profesor cuenta con el olvido. Pero sabe tambien que lo que olvidó uno, lo recuerda otro. Y, al final, el grupo entero concurre, durante la lección siguiente, en recordar la mayoría de las expresiones usadas. Y que se volverán a utilizar en las otras lecciones.Villégier Jean. Les étonnements d'un vieux pédagogue. In: Cahiers de l'APLIUT, volume 4, numéro 4, 1985. pp. 6-12

L'Amérique latine et la France [Les langues néo-latines]

Villégier J. L'Amérique latine et la France [Les langues néo-latines]. In: Femmes Diplômées, n°15-16, 1955. pp. 6-11

Je l’ai rencontrée sur le tard

Je l’ai rencontrée sur le tard, quelques trop rares fois, toujours en mêmes circonstances. Aux soirs de première, rideau chargé sur l’ultime salut, le metteur en scène ouvre la porte qui sépare les deux espaces constitutifs du théâtre. Il longe la salle déserte, se faufile dans le corridor où quelques attardés remettent les derniers tickets aux demoiselles du vestiaire. Bourdonnement indistinct d’exclamations et de rires. Le public s’est désassemblé. Les mécontents, car il en fut, ont pris la..

El control y la calificación

The present article defends the idea that we must evaluate through control, fundamentally, how the pupil is improving his ability to understand a foreign speaker, to express himself in a foreign language and use this capacity in different ways. Free Oral inspections and reports are the two main activities that can be tested, which must be controlled and evaluated. The control must be efficient, moderate and as comprehensive as possible. It must have as its objetive the judgment, along with the work, of the merit, effort and progress of each pupil. It should not be visibly continous and reiterative, nor should it be too precise, contrived or negative. And above all it mustn't occupy too much class time, thus avoiding reducing the precious time dedicated in the main to acquisition and practiceA través del presente artículo se defiende la idea de que a través del control se debe evaluar, fundamentalmente, en qué medida el alumno va siendo progresivamente apto para comprender a un interlocutor extranjero, para expresarse él mismo en lengua extranjera y para utilizar esta capacidad bajo sus diversas formas. Las intervenciones orales libres y las declamaciones constituyen las dos actividades principales, con capacidad probatoria, que hay que controlar y calificar. El control debe ser eficaz, moderado y lo más alentador posible. Debe tener por finalidad medir, junto con el trabajo, el mérito, el valor y los progresos de cada uno. No debe ser ostensiblemente continuo y reiterativo, ni puntilloso, ni rebuscado, ni negativo. Y sobre todo no debe ocupar mucho tiempo de clase, evitando así reducir un tiempo precioso destinado prioritariamente a la adquisición y a la práctic

El control y la calificación

The present article defends the idea that we must evaluate through control, fundamentally, how the pupil is improving his ability to understand a foreign speaker, to express himself in a foreign language and use this capacity in different ways. Free Oral inspections and reports are the two main activities that can be tested, which must be controlled and evaluated. The control must be efficient, moderate and as comprehensive as possible. It must have as its objetive the judgment, along with the work, of the merit, effort and progress of each pupil. It should not be visibly continous and reiterative, nor should it be too precise, contrived or negative. And above all it mustn't occupy too much class time, thus avoiding reducing the precious time dedicated in the main to acquisition and practiceA través del presente artículo se defiende la idea de que a través del control se debe evaluar, fundamentalmente, en qué medida el alumno va siendo progresivamente apto para comprender a un interlocutor extranjero, para expresarse él mismo en lengua extranjera y para utilizar esta capacidad bajo sus diversas formas. Las intervenciones orales libres y las declamaciones constituyen las dos actividades principales, con capacidad probatoria, que hay que controlar y calificar. El control debe ser eficaz, moderado y lo más alentador posible. Debe tener por finalidad medir, junto con el trabajo, el mérito, el valor y los progresos de cada uno. No debe ser ostensiblemente continuo y reiterativo, ni puntilloso, ni rebuscado, ni negativo. Y sobre todo no debe ocupar mucho tiempo de clase, evitando así reducir un tiempo precioso destinado prioritariamente a la adquisición y a la práctic