1,137 research outputs found

    Influence d’un atelier de prise de notes sur la capacité d’étudiants du collégial à restituer les idées principales d’un texte de philosophie : une vision contrastive étudiants – professeurs de philosophie

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    Cette recherche avait pour but de déterminer quelle était l’influence de l’administration d’un atelier de prise de notes dans le cadre du premier cours de philosophie du collégial qui se donnait au début de la deuxième session des apprenants. Elle se situait dans le cadre d’une recherche intervention et le point de vue des parties prenantes, à savoir les apprenants et les enseignants, était recueilli de façon qualitative. Les premiers, forts d’une expérience d’une session au niveau collégial, ont exprimé le besoin de suivre une formation formelle liée à la prise de notes, quand bien même celle-ci leur demanderait un effort supplémentaire. Les deuxièmes nous ont fait part de leurs préoccupations en ce qui a trait à la qualité des notes de leurs étudiants. Nous avons demandé aux répondants de restituer les thèmes principaux de deux textes équivalents distribués de façon simultanée en fonction des rangées (première rangée – premier texte, deuxième rangée – deuxième texte, etc.), puis nous avons interverti l’ordre de distribution des textes après l’atelier. Lors de l’analyse des résultats, nous avons constaté que les répondants avaient restitué les thèmes dans un ordre d’importance plus approprié après l’atelier qu’avant celui-ci, mais nous avons surtout remarqué une amélioration significative dans l’emploi des stratégies de prise de notes et dans la constance de leur utilisation tout au long du second texte étudié.This research was conducted to determine what influence of a taking notes workshop had on college students attending their first philosophical course during their second college session was. This intervention research was following the model of qualitative methods in intervention research in order to gather points of view of different stakeholders: college students and college teachers. College students who already completed one full college session expressed the need to receive formal training related to taking notes, even though it would require them to invest extra time and effort into their overall studies. In addition, many college teachers also expressed their concerns regarding the quality and effectiveness of their students’ note taking. To fulfill the study, the respondents were given two equivalent texts simultaneously based on the rows the students were sitting in (first row - first text, second row - second text). The respondents were asked to read the texts, take notes, and state the main topics of these texts. After the workshop, the order of distribution of texts has been inverted and the students were asked to complete the same task with the knowledge received. When analyzing the results, it was established that the respondents had relayed the topics in a much more appropriate order of importance after completing the workshop than before it. Most importantly, a significant improvement was observed in the usage of note-taking strategies and their steadier practical application throughout the second text the respondents had to work on

    Interference effects in two-photon ATI by multiple orders high harmonics with random or locked phases

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    We numerically study 2-photon processes using a set of harmonics from a Ti:Sapphire laser and in particular interference effects in the Above Threshold Ionization spectra. We compare the situation where the harmonic phases are assumed locked to the case where they have a random distribution. Suggestions for possible experiments, using realistic parameters are discussed.Comment: 11 pages, 13 figures, LaTe

    100  kHz Yb-fiber laser pumped 3  μm optical parametric amplifier for probing solid-state systems in the strong field regime

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    We report on a laser source operating at 100 kHz repetition rate and delivering 8 ÎĽJ few-cycle mid-IR pulses at 3 ÎĽm. The system is based on optical parametric amplification pumped by a high repetition rate Yb-doped femtosecond fiber-chirped amplifier. This high-intensity ultrafast system is a promising tool for strong-field experiments (up to 50 GV/m and 186 T) in low ionization potential atomic and molecular systems, or solid-state physics with coincidence measurements. As a proof of principle, up to the sixth harmonic has been generated in a 1 mm zinc selenide sample

    Environmentally Persistent Free Radicals: Insights on a New Class of Pollutants

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    © 2018 American Chemical Society. Environmentally persistent free radicals, EPFRs, exist in significant concentration in atmospheric particulate matter (PM). EPFRs are primarily emitted from combustion and thermal processing of organic materials, in which the organic combustion byproducts interact with transition metal-containing particles to form a free radical-particle pollutant. While the existence of persistent free radicals in combustion has been known for over half-a-century, only recently that their presence in environmental matrices and health effects have started significant research, but still in its infancy. Most of the experimental studies conducted to understand the origin and nature of EPFRs have focused primarily on nanoparticles that are supported on a larger micrometer-sized particle that mimics incidental nanoparticles formed during combustion. Less is known on the extent by which EPFRs may form on engineered nanomaterials (ENMs) during combustion or thermal treatment. In this critical and timely review, we summarize important findings on EPFRs and discuss their potential to form on pristine ENMs as a new research direction. ENMs may form EPFRs that may differ in type and concentration compared to nanoparticles that are supported on larger particles. The lack of basic data and fundamental knowledge about the interaction of combustion byproducts with ENMs under high-temperature and oxidative conditions present an unknown environmental and health burden. Studying the extent of ENMs on catalyzing EPFRs is important to address the hazards of atmospheric PM fully from these emerging environmental contaminants

    Single-shot CEP drift measurement at arbitrary repetition rate based on dispersive Fourier transform

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    This paper presents a single-shot technique for measuring CEP. The Temporal dispersion based One-shot Ultrafast Carrier envelope phase Analysis method (TOUCAN) is an arbitrary repetition rate single-shot CEP drift measurement technique based on dispersive Fourier transformations and has been experimentally tested at 100 kHz. TOUCAN was validated by a direct comparison of decimated data with an independent traditional CEP drift measurement technique. The impact of a temporal jitter on the CEP drift measurement is investigated and a new mitigation technique is shown to produce high accuracy jitter-free CEP drift extraction. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

    Vanishing Geometric Discord in Non-Inertial Frames

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    We show that quantum field correlations in non-inertial frames are not as persistent as previously thought. We perform a simple calculation showing that the geometric discord, a measure of quantum correlations, does decay to zero in the infinite acceleration limit. This result is seen to be a natural and expected consequence of considering correlations in an infinite dimensional system, and it sheds doubt on the existence of useable quantum correlations in this regime. We contrast our results with previous research showing that the acceleration-induced degradation of quantum discord was not strong enough to extinguish discord in the large acceleration limit.Comment: 9 pages, revtex4, 2 figures. V2 Added journal reference and updated to published versio

    Impact of Degree of Commissural Opening After Percutaneous Mitral Commissurotomy on Long-Term Outcome

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    ObjectivesWe sought to evaluate the prognostic value of the degree of commissural opening (CO) on outcome.BackgroundCommissural opening is the main mechanism by which the mitral valve area (MVA) increases after percutaneous mitral commissurotomy (PMC) but its impact on long-term outcome has never been evaluated.MethodsOf 1,024 consecutive patients with severe MS who underwent PMC, degree of CO was prospectively evaluated in 875 patients (age 48 ± 13 years, female 83%, New York Heart Association (NYHA) functional class III/IV 75%) with good immediate PMC results (MVA ≥1.5 cm2 and no mitral regurgitation >2/4). These 875 patients were divided into 3 groups: both commissures only partially opened or not split (Group 1, n = 189), 1 commissure completely split (Group 2; n = 459), and both commissures completely split (Group 3; n = 227). During a follow-up of 55 ± 28 months, following clinical end points were collected: death, cardiovascular death, need for mitral valve surgery or repeat dilation, and NYHA functional class.ResultsBefore PMC, patients in Group 1 were older, more often in NYHA functional class III/IV, but MVA and mean gradient were not different (p ≥ 0.50). Immediately after PMC, there were significant differences between groups with regard to mean gradient (Group 1, 5.1 ± 2.1 mm Hg; Group 2, 4.5 ± 1.7 mm Hg; Group 3, 4.0 ± 1.6 mm Hg; p < 0.0001) and MVA (Group 1, 1.8 ± 0.2 cm2; Group 2, 1.9 ± 0.2 cm2; Group 3, 2.1 ± 0.3 cm2; p < 0.0001). The 10-year rate of good functional results (survival without need for mitral surgery or repeat dilation and NYHA functional class I or II at last follow-up) was significantly higher in Group 3 (76 ± 5%) than in Groups 1 and 2 (39 ± 8% and 57 ± 11%, respectively; p < 0.0001). In multivariable analysis, either the degree of CO or the MVA was an independent predictor of good late functional results (p < 0.05).ConclusionsComplete CO is associated with larger MVA, smaller gradients, and functional improvement. The degree of CO provides important prognostic information and thus should be systematically evaluated during and after PMC and considered as a complementary measure of the procedural success in addition to the MVA, not always easy to assess
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