Factors Influencing the Evolution of Vocational Teachers’ Beliefs and Practices Related to Classroom Management during Teacher Education

Two studies were conducted to investigate the evolution of 71 Swiss vocational teachers’ classroom management as a result of the inputs of a teacher education program, and to identify the factors that encouraged or impeded teacher change. Study 1 consisted of a longitudinal survey, and Study 2 of interviews. Longitudinal analyses were performed using a multilevel approach. This mixed-method study revealed that vocational teachers’ classroom management evolved towards the beliefs and practices encouraged by the teacher education program. Years of prior teaching experience and motivations for choosing teaching were found to moderate teachers’ evolutions. Moreover, influential people, providing alternative strategies for teachers to try in their classrooms, and questioning teaching practices, were found to influence teachers’ change. Finally, this study emphasizes the importance of the congruence between teacher education and the teaching context as well as the influence of school norms on teacher change

Interlaced spin grating for optical wave filtering

Interlaced Spin Grating is a scheme for the preparation of spectro-spatial periodic absorption gratings in a inhomogeneously broadened absorption profile. It relies on the optical pumping of atoms in a nearby long-lived ground state sublevel. The scheme takes advantage of the sublevel proximity to build large contrast gratings with unlimited bandwidth and preserved average optical depth. It is particularly suited to Tm-doped crystals in the context of classical and quantum signal processing. In this paper, we study the optical pumping dynamics at play in an Interlaced Spin Grating and describe the corresponding absorption profile shape in an optically thick atomic ensemble. We show that, in Tm:YAG, the diffraction efficiency of such a grating can reach 18.3% in the small angle, and 11.6% in the large angle configuration when the excitation is made of simple pulse pairs, considerably outperforming conventional gratings.Comment: 11 pages, 13 figures in Physical Review A, 201

Les croyances pédagogiques et identitaires des enseignants de la formation professionnelle : le rôle de l’expérience d’enseignement et de la formation pédagogique

Les croyances des enseignants sont liées aux pratiques d’enseignement et ainsi,indirectement, aux apprentissages des élèves, faisant d’elles un sujet important. Le but de cette étude était de mettre en évidence l’effet de l’expérience et de la formation pédagogique sur les croyances pédagogiques et identitaires des enseignants de la formation professionnelle en Suisse romande. Au total, 390 enseignants ont participé à l’étude en répondant à un questionnaire. Les analyses de variance conduites montrent que tant les années d’expérience que la formation pédagogique ainsi que leur interaction ont un effet sur l’adhésion aux croyances considérées. Les questions de l’immuabilité des croyances et de l’importance de la formation pédagogique pour le développement de certaines croyances sont abordées en conclusio

Les motivations à devenir enseignant : revue de la question chez les enseignants de première et deuxième carrière

Les récents phénomènes de pénurie d’enseignants et de diminution de l’attrait pour ce métier amènent à s’interroger sur les motivations à devenir enseignant. Cette note synthétise les recherches qui ont abordé ces motivations, en se penchant non seulement sur les enseignants dont il s’agit de la première carrière, mais également sur ceux qui ont choisi le métier suite à une réorientation professionnelle. Les effets des diverses motivations sont ensuite analysés. Le cadre théorique récemment développé par Watt et Richardson est décrit et proposé pour guider les recherches dans ce champ. En conclusion, des suggestions de recherches sont formulées afin de mieux comprendre les motivations à enseigner et leurs effets.Teacher shortage and the decreasing attractiveness of the teaching profession raise questions about the reasons to become a teacher. Research analyzing the motives of first-career but also second-career teachers is reviewed in this paper. The consequences of these various motives are then examined. Watt and Richardson’s recently-developed theoretical framework is described and offered as a guide to research in this field. Finally, suggestions for further research are made to better understand the motives behind the decision to become a teacher and its effects.Los recientes fenómenos de penuria de profesores y la disminución de la atracción por esa carrera invitan a cuestionarnos sobre las motivaciones para llegar a ser profesor. Esta nota sintetiza las investigaciones que estudiaron dichas motivaciones, interesándose no sólo por los profesores para quienes es la primera carrera, sino también interesándose por los que eligieron el oficio tras una reorientación profesional. A continuación se analizan las consecuencias de las diversas motivaciones. Se presenta y se propone el marco teórico recientemente desarrollado por Watt y Richardson para guiar las investigaciones en ese campo. En conclusión, se formulan sugerencias de investigaciones para comprender mejor las motivaciones que impulsan a enseñar y sus efectos.Die neueren Phänomene von Lehrermangel und von Senkung des Interesses für diesen Beruf führen uns dazu, uns Fragen über die Motivation zu stellen, die man aufbringen muss, um Lehrer zu werden. Dieser Text fasst die Forschungsarbeiten zusammen, die sich mit solchen Motivationen beschäftigt haben und interessiert sich nicht nur für Lehrer, bei denen es sich um den ersten Beruf handelt, sondern auch für diejenigen, die diese Karriere nach einem Berufwechsel gewählt haben. Die Konsequenzen der verschiedenen Motivationen wurden dann analysiert. Der neulich von Watt und Richardson entwickelte theoretische Rahmen wird beschrieben und dann angeboten, um die Forschungsarbeiten auf diesem Gebiet zu führen. Zum Schluss werden Forschungsansätze angeboten, um die Motivationen zum Lehren und ihre Auswirkungen besser zu verstehen

Métacognition et croyances motivationnelles : un mariage de raison

Bien que l’importance des croyances motivationnelles pour l’apprentissage et la réussite scolaire soit passablement reconnue, les chercheurs ne se sont que récemment intéressés aux relations entre ces croyances et les aspects métacognitifs de l’apprentissage, notamment dans le cadre des modèles de l’apprentissage autorégulé. Nous proposons une synthèse des positions théoriques ainsi que d’un certain nombre d’études empiriques s’étant penchées sur les articulations entre métacognition et motivation. Pour conclure, les implications pour l’enseignement, l’apprentissage et les interventions de type éducation cognitive sont discutées.Although the prominence of motivational beliefs in learning and academic achievement has been largely acknowledged, researchers have only recently investigated the relations between these beliefs and the metacognitive aspects of learning, especially as part of self-regulated learning. We provide an outline of the different theories and of a number of empirical studies focused on the connections between metacognition and motivation. The implications in terms of teaching, learning and cognitive education are finally discussed.Aunque la importancia de las creencias que permiten la motivación en el aprendizaje y en el éxito escolar es bastante reconocida, sólo se interesaron hace poco los investigadores en las relaciones entre estas creencias y los aspectos metacognitivos del aprendizaje, particularmente en el marco de los modelos del aprendizaje autorregulado. Proponemos aquí una síntesis de las posiciones teóricas así como la de unos cuantos estudios empíricos dedicados al estudio de las articulaciones entre meta cognición y motivación. A modo de conclusión, se ven puestos en tela de juicio las implicaciones para la enseñanza, el aprendizaje y las intervenciones de tipo educación cognitiva.Obwohl die Bedeutung des Motivationsglauben für das Lernen und den Schulerfolg allseits angenommen wird, haben sich die Forscher erst seit kurzem für die Beziehungen zwischen diesen Überzeugungen und den metakognitiven Aspekten der Ausbildung interessiert, besonders im Rahmen des selbstregulierten Lernens. Wir bieten eine Synthese der theoretischen Auffassungen so wie eine gewisse Zahl empirischer Studien an, die sich für die Artikulierungen zwischen Metakognition und Motivation interessiert haben. Schließlich werden die Einwirkungen für Unterricht und Ausbildung sowie die Beiträge der kognitiven Erziehung erörtert

Experimental Study of the Human Ability to Deliberately Excite a Flexible Floor

peer reviewedHuman-structure interactions are not completely understood yet. This paper presents an experimental study focusing on the interaction between a human and a flexible support, with a major aim to better understand how the behavior of a human subject, bouncing on a flexible structure, adapts to the support motion. Exploratory experiments are undertaken with a 7m-span timber footbridge tested in the Human Motion Analysis Laboratory of the University of Liege. The movements of the coupled system composed of the subject and the footbridge are recorded by Motion Capture technology; the subject\textquoteright{}s 3-D body motion is defined by three important angles: ankle, knee and hip. The interaction between the subject and the footbridge is also quantified by means of force platform measurements. The experiments indicate an influence of the support amplitude and natural frequency on the phase shift between the oscillatory floor motion and the three angles characterizing the motion

Raman probing of uniaxial strain in individual single-wall carbon nanotubes in a composite material

International audienceThe temperature dependence of the Raman spectrum of a gelatine-based composite material doped with single-walled carbon nanotubes (SWNT@gelatin) is reported. A significant up-shift of the G-mode frequency is observed when the temperature is decreased from room temperature to 20~K. This frequency shift is significantly stronger than the one found for pure thermal effects. In contrast, the features of the radial breathing modes (frequencies and width) display no significant change in the same temperature range. These results are well understood by considering a uniaxial strain on the nanotube induced by the thermal expansitivity mismatch between the nanotube and the surrounding matrix

Daily water fluxes and water balance in two rain forest lianas of Southern Cameroon

En forêt littorale humide du Sud Cameroun, près de Campo, les débits de sève de deux grandes lianes Tetracera podotricha (Dilleniaceae) et Combretum confertum (Combretaceae) ont été mesurés pendant trois journées en saison des pluies (25, 31 octobre et 1 novembre 1991), par la méthode des débitmètres thermiques (capteurs Dynamax Inc.). Les mesures dans les cimettes de ces deux lianes, déployées dans la canopée supérieure, ont été rendues possibles grâce à l'utilisation du «Radeau des Cimes». Sur l'ensemble des trois journées de mesures traitées (deux sites forestiers exploités), il ressort que 1) Les courbes journalières des densités de flux de photons photosynthétiquement actifs (PPFD) et des flux de sève dans les cimettes des deux lianes, installées à 35 m de hauteur, sont bien en phase (...

20 GHz instantaneous bandwidth RF spectrum analyzer with high time-resolution

International audienceWe report on the experimental demonstration of a multi-gigahertz bandwidth RF spectrum analyzer exhibiting a resolution below 20 MHz, based on spectral hole burning in a rare-earth ion-doped crystal. To be compatible with demanding real-time spectrum monitoring applications, our demonstrator is designed to reach a high time resolution. For this purpose, we implemented the so-called "rainbow" architecture in which the spectral components of the incoming signal are angularly separated by the crystal, and are then acquired with a pixelated photodetector. The Tm 3+ :YAG crystal is programmed with a semiconductor DFB laser which frequency scan is servo-controlled and synchronized with the angular scan of a resonant galvanometric mirror, while a high-speed camera is used to acquire the spectra. In the perspective of future implementation within a system, the crystal is cooled below 4 K with a closed-cycle cryostat. With this setup, we have been able to monitor and record the spectrum of complex microwave signals over an instantaneous bandwidth above 20 GHz, with a time resolution below 100 µs, 400 resolvable frequency components and a probability of intercept of 100 %

Effect of bicarbonate and lactate buffer on glucose and lactate metabolism during hemodiafiltration in patients with multiple organ failure

Objective: To compare the effects of sodium bicarbonate and lactate for continuous veno-venous hemodiafiltration (CVVHDF) in critically ill patients. Design and settings: Prospective crossed-over controlled trial in the surgical and medical ICUs of a university hospital. Patients: Eight patients with multiple organ dysfunction syndrome (MODS) requiring CVVHDF. Intervention: Each patient received the two buffers in a randomized sequence over two consecutive days. Measurements and results: The following variables were determined: acid-base parameters, lactate production and utilization (13C lactate infusion), glucose turnover (6,62H2-glucose), gas exchange (indirect calorimetry). No side effect was observed during lactate administration. Baseline arterial acid-base variables were equal with the two buffers. Arterial lactate (2.9 versus 1.5mmol/l), glycemia (+18%) and glucose turnover (+23%) were higher in the lactate period. Bicarbonate and glucose losses in CVVHDF were substantial, but not lactate elimination. Infusing 13C lactate increased plasma lactate levels equally with the two buffers. Lactate clearance (7.8±0.8 vs 7.5±0.8ml/kg per min in the bicarbonate and lactate periods) and endogenous production rates (14.0±2.6 vs 13.6±2.6mmol/kg per min) were similar. 13C lactate was used as a metabolic substrate, as shown by 13CO2 excretion. Glycemia and metabolic rate increased significantly and similarly during the two periods during lactate infusion. Conclusion: Lactate was rapidly cleared from the blood of critically ill patients without acute liver failure requiring CVVHDF, being transformed into glucose or oxidized. Lactate did not exert undesirable effects, except moderate hyperglycemia, and achieved comparable effects on acid-base balance to bicarbonat