Collège de Bois-de-Boulogne

ABSTRACT In this paper we complete the presentation of a new hybrid 2 × 2D flux transport dynamo (FTD) model of the solar cycle based on the Babcock–Leighton mechanism of poloidal magnetic field regeneration via the surface decay of bipolar magnetic regions (BMRs). This hybrid model is constructed by allowing the surface flux transport (SFT) simulation described in Lemerle et al. to provide the poloidal source term to an axisymmetric FTD simulation defined in a meridional plane, which in turn generates the BMRs required by the SFT. A key aspect of this coupling is the definition of an emergence function describing the probability of BMR emergence as a function of the spatial distribution of the internal axisymmetric magnetic field. We use a genetic algorithm to calibrate this function, together with other model parameters, against observed cycle 21 emergence data. We present a reference dynamo solution reproducing many solar cycle characteristics, including good hemispheric coupling, phase relationship between the surface dipole and the BMR-generating internal field, and correlation between dipole strength at cycle maximum and peak amplitude of the next cycle. The saturation of the cycle amplitude takes place through the quenching of the BMR tilt as a function of the internal field. The observed statistical scatter about the mean BMR tilt, built into the model, acts as a source of stochasticity which dominates amplitude fluctuations. The model thus can produce Dalton-like epochs of strongly suppressed cycle amplitude lasting a few cycles and can even shut off entirely following an unfavorable sequence of emergence events.

Abstract The dynamic activity of stars such as the Sun influences (exo)planetary space environments through modulation of stellar radiation, plasma wind, particle and magnetic fluxes. Energetic solar-stellar phenomena such as flares and coronal mass ejections act as transient perturbations giving rise to hazardous space weather. Magnetic fields – the primary driver of solar-stellar activity – are created via a magnetohydrodynamic dynamo mechanism within stellar convection zones. The dynamo mechanism in our host star – the Sun – is manifest in the cyclic appearance of magnetized sunspots on the solar surface. While sunspots have been directly observed for over four centuries, and theories of the origin of solar-stellar magnetism have been explored for over half a century, the inability to converge on the exact mechanism(s) governing cycle to cycle fluctuations and inconsistent predictions for the strength of future sunspot cycles have been challenging for models of the solar cycles. This review discusses observational constraints on the solar magnetic cycle with a focus on those relevant for cycle forecasting, elucidates recent physical insights which aid in understanding solar cycle variability, and presents advances in solar cycle predictions achieved via data-driven, physics-based models. The most successful prediction approaches support the Babcock-Leighton solar dynamo mechanism as the primary driver of solar cycle variability and reinforce the flux transport paradigm as a useful tool for modelling solar-stellar magnetism.

Abstract The composition of vinyl acetate–butyl acrylate copolymers obtained with batch emulsion polymerization have been studied by 1 H‐NMR. Using the integrated copolymerization Meyer–Lowry equation, the apparent reactivity ratios of the two monomers were calculated as 10.67 for r 1 , the reactivity ratio of butyl acrylate (BA), and 0.024 for r 2 , the reactivity ratio of vinyl acetate (VAC). These results were compared with those obtained by other methods.

Context. Two candidate mechanisms have recently been considered with regard to the nonlinear modulation of solar cycle amplitudes. Tilt quenching (TQ) comprises the negative feedback between the cycle amplitude and the mean tilt angle of bipolar active regions relative to the azimuthal direction. Latitude quenching (LQ) consists of a positive correlation between the cycle amplitude and average emergence latitude of active regions. Aims. Here, we explore the relative importance and the determining factors behind the LQ and TQ effects. Methods. We systematically probed the degree of nonlinearity induced by TQ and LQ, as well as a combination of both using a grid based on surface flux transport (SFT) models. The roles played by TQ and LQ are also explored in the successful 2×2D dynamo model, which has been optimized to reproduce the statistical behaviour of real solar cycles. Results. The relative importance of LQ versus TQ is found to correlate with the ratio u 0 / η in the SFT model grid, where u 0 is the meridional flow amplitude and η is the diffusivity. An analytical interpretation of this result is given, further demonstrating that the main underlying parameter is the dynamo effectivity range, λ R , which is, in turn, determined by the ratio of equatorial flow divergence to diffusivity. The relative importance of LQ versus TQ is shown to scale as $ C_1+C_2/\lambda_R^2 $. The presence of a latitude quenching effect is seen in the 2×2D dynamo, contributing to the nonlinear modulation by an amount that is comparable to TQ. For other dynamo and SFT models considered in the literature, the contribution of LQ to the modulation covers a broad range – from entirely insignificant to serving as a dominant source of feedback. On the other hand, the contribution of a TQ effect (with the usually assumed amplitude) is never shown to be negligible.

We examine the impact of surface inflows into activity belts on the operation of solar cycle models based on the Babcock–Leighton mechanism of poloidal field regeneration. Towards this end we introduce in the solar cycle model of Lemerle & Charbonneau (2017. ApJ 834 : 133) a magnetic flux-dependent variation of the surface meridional flow based on the axisymmetric inflow parameterization developped by Jiang et al. (2010. ApJ 717 : 597). The inflow dependence on emerging magnetic flux thus introduces a bona fide nonlinear backreaction mechanism in the dynamo loop. For solar-like inflow speeds, our simulation results indicate a decrease of 10–20% in the strength of the global dipole building up at the end of an activity cycle, in agreement with earlier simulations based on linear surface flux transport models. Our simulations also indicate a significant stabilizing effect on cycle characteristics, in that individual cycle amplitudes in simulations including inflows show less scatter about their mean than in the absence of inflows. Our simulations also demonstrate an enhancement of cross-hemispheric coupling, leading to a significant decrease in hemispheric cycle amplitude asymmetries and temporal lag in hemispheric cycle onset. Analysis of temporally extended simulations also indicate that the presence of inflows increases the probability of cycle shutdown following an unfavorable sequence of emergence events. This results ultimately from the lower threshold nonlinearity built into our solar cycle model, and presumably operating in the sun as well.

To date, the only curative treatment for high-risk or refractory hematologic malignancies non-responsive to standard chemotherapy is allogeneic hematopoietic transplantation (allo-HCT). Acute graft-versus-host disease (GVHD) is a donor T cell-mediated immunological disorder that is frequently fatal and the leading cause of non-relapse mortality (NRM) in patients post allo-HCT. The pathogenesis of acute GVHD involves recognition of minor and/or major HLA mismatched host antigens by donor T cells followed by expansion, migration and finally end-organ damage due to combination of inflammatory cytokine secretion and direct cytotoxic effects. The endothelium is a thin layer of endothelial cells (EC) that line the innermost portion of the blood vessels and a key regulator in vascular homeostasis and inflammatory responses. Endothelial cells are activated by a wide range of inflammatory mediators including bacterial products, contents released from dying/apoptotic cells and cytokines and respond by secreting cytokines/chemokines that facilitate the recruitment of innate and adaptive immune cells to the site of inflammation. Endothelial cells can also be damaged prior to transplant as well as by alloreactive donor T cells. Prolonged EC activation results in dysfunction that plays a role in multiple post-transplant complications including but not limited to veno-occlusive disease (VOD), transplant associated thrombotic microangiopathy (TA-TMA), and idiopathic pneumonia syndrome. In this mini review, we summarize the biology of endothelial cells, factors regulating EC activation and the role of ECs in inflammation and GVHD pathogenesis.

An algebraic method for the reconstruction and potentially prediction of the solar dipole moment value at sunspot minimum (known to be a good predictor of the amplitude of the next solar cycle) was suggested in the first paper in this series. The method sums up the ultimate dipole moment contributions of individual active regions in a solar cycle: for this, detailed and reliable input data would in principle be needed for thousands of active regions in a solar cycle. To reduce the need for detailed input data, here we propose a new active region descriptor called ARDoR (Active Region Degree of Rogueness). In a detailed statistical analysis of a large number of activity cycles simulated with the 2 × 2D dynamo model we demonstrate that ranking active regions by decreasing ARDoR, for a good reproduction of the solar dipole moment at the end of the cycle it is sufficient to consider the top N regions on this list explicitly, where N is a relatively low number, while for the other regions the ARDoR value may be set to zero. For example, with N = 5 the fraction of cycles where the dipole moment is reproduced with an error exceeding ±30% is only 12%, significantly reduced with respect to the case N = 0, i.e. ARDoR set to zero for all active regions, where this fraction is 26%. This indicates that stochastic effects on the intercycle variations of solar activity are dominated by the effect of a low number of large “rogue” active regions, rather than the combined effect of numerous small ARs. The method has a potential for future use in solar cycle prediction.

Cette étude a été réalisée auprès de 12 208 cégépiens du régulier, inscrits à la session d’automne 2014 et provenant de huit cégeps situés dans différentes régions du Québec. Elle mesure l’ampleur des besoins socioaffectifs des répondants et l’utilisation des services d’aide qui leur sont offerts. Les résultats indiquent que les trois quarts des répondants ont recours à de tels services d’aide pour des problèmes autres que scolaires. Les principaux motifs de ce recours sont la satisfaction, la curiosité et la souffrance. Les résultats montrent aussi que 17,4 % des répondants ont ressenti beaucoup ou énormément de détresse et que 35,1 % ont éprouvé souvent ou tout le temps de l’anxiété. Les principaux facteurs explicatifs de la détresse et de l’anxiété sont les conflits familiaux, la pression liée au rendement scolaire, l’intimidation et les pensées suicidaires. Ainsi, 29,3 % disent qu’ils ont vécu beaucoup ou énormément de détresse à l’égard des conflits familiaux; 33,3 % ont éprouvé beaucoup ou énormément de pression liée à la performance scolaire; 11,9 % ont ressenti beaucoup ou énormément de détresse liée à l’intimidation et 18,3 % des répondants affirment avoir eu des pensées suicidaires et parmi eux, 7,3 % disent en avoir eues souvent ou tout le temps. Enfin, certains préjugés à l’égard de la santé mentale apparaissent comme un frein significatif à l’utilisation des ressources d’aide.

Une première partie de ce texte a présenté une nouvelle théorie de la psyché. Cette nouvelle théorie, dans la mesure où elle remet au travail le processus mémoriel, nous introduit, au plan de la méthode analytique, au nouveau paradigme de la transitionnalité en complémentarité avec le paradigme plus classique de la remémoration. Chemin faisant, nous posons un nouveau regard sur le transfert et l’interprétation.

This article focuses on the attitude of practicing teachers toward teaching science and technology (S&T). It reports the results of a study conducted with 110 late-elementary school teachers in order to assess their attitude at the end of a particular training intervention. The intervention was based on pairing teachers with pre-university science students (aged 17–19). In the experimental group, all 42 teachers were accompanied by a pre-university student in their classroom to conduct activities on topics included in the intervention. We used a mixed-method approach, combining pretest, posttest, and interviews. The interaction effect of factorial ANOVAs was significant for the subconstructs of self-efficacy, context-dependency, and behavioral intention to teach specific S&T concepts. The interviews suggest that the presence of pre-university students in the classroom had a beneficial effect on teachers’ attitude.

L'accucil d'un enfant atteint d'une déficience provoque chez les parents un stress psychologique intense et ceux-ci sont alors confrontés à une situation de crise. C'est par le cheminement à travers le processus de deuil de l'enfant désiré «parfait» que les parents parviennent à s'adapter à la situation, plusieurs auteurs ont décrit une séquence de réactions normales par laquelle doivent passer les parents qui donnent naissance à un enfant atteint d'une déficience. Cette situation difficile affecte les parents dans les différentes sphegres d'adaptation, c'est-à-dire en tant qu'individu, conjoint, parent et en relation avec l'entourage. Des difficultés d'adaptation, qui ne sont pas nécessairement reliées à la gravité du probléme, sont susceptibles de se manifester chez les parents et la famille entière. De méme, la facon de réagir de chacun des membres aura un impact sur tout le système familial.

Cet article s’intéresse aux initiatives citoyennes qui prennent place dans le contexte des désappropriations associées à la mondialisation économique néolibérale et de la redéfinition du rapport au politique des citoyens. À partir de l’exemple des Initiatives de transition et plus précisément du cas de Villeray en transition (VET), les auteurs explorent le cadre théorique des Initiatives citoyennes d’appropriation de l’espace habité (ICAEH) ainsi que les dimensions sociales, symboliques et matérielles de cette dernière. Ces nouvelles formes d’initiatives se réalisent dans un rapport au politique caractérisé par une logique ascendante (en termes de participation citoyenne), une démarche réflexive, horizontale et conscientisante d’ empowerment entre citoyens. C’est la volonté de créer un « meilleur quartier sans pétrole » dans une perspective optimiste et de développer un « art de vivre local » qui amène les citoyens comme ceux de VET à repenser leurs pratiques sociales de voisinage et à tisser des réseaux inclusifs au sein de Villeray. En s’appropriant symboliquement et socialement l’espace habité, les citoyens transforment progressivement les pratiques matérielles de leur quartier.

Typical object-oriented (OO) systems implement several functional features that are interwoven into class hierarchies. In the absence of aspect-oriented techniques to develop and compose these features, developers resort to object-oriented design and programming idioms to separate features as well as possible. Given a legacy OO system, discovering existing functional features helps understand the design of the system and extract these features to ease their maintenance and reuse. We want to discover candidate functional features in OO systems. We first define functional features and then discuss the footprints that such features are likely to leave in an OO system. We identify three such footprints: (1) multiple inheritance, (2) delegation, and (3) ad-hoc. We develop a set of algorithms for identifying such footprints in OO code and implemented them for the Java language using Eclipse JDT. In this article, we present the algorithms, and the results of applying the corresponding tools on five open-source systems: FreeMind, JavaWebMail, JHotDraw, JReversePro, and Lucene. Our experimental results show that: (1) the different algorithms can identify interesting and useful candidate functional features in OO systems, (2) they can identify opportunities for refactoring, and (3) they are complementary and could help developers.

The objective of this study is to take the initial steps toward developing novel antibiotics to counteract the escalating problem of antimicrobial and bacterial persistence, particularly in relation to biofilms. Our approach involves emulating the structural characteristics of cationic antimicrobial peptides. To circumvent resistance development, we have designed a library of bis-benzimidazolium salts that selectively target the microbial membranes in a nonspecific manner. To explore their structure–activity relationship, we conducted experiments using these compounds on various pathogens known for their resistance to conventional antibiotics, including Gram-positive methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE), and Gram-negative Escherichia coli (E. coli). Notably, two bis-benzimidazolium salts exhibited robust antimicrobial activity while maintaining a high level of selectivity compared with mammalian cells. Our investigations revealed significant antibiofilm activity, as these compounds rapidly acted against established biofilms. In addition, bis-benzimidazolium compounds exhibited consistent results in resistance development and cross-resistance studies. Consequently, amphiphilic bis-benzimidazolium salts hold promise as potential candidates to combat resistance-associated infections.

INTRODUCTION: Patients with inflammatory bowel disease (IBD) are at higher risk of thromboembolic events (TE). In pediatric-onset IBD, more data on incidence and risk factors of venous (VTE) and arterial events (ATE) at the population level are needed to guide thromboprophylaxis. METHODS: All patients aged ≤ 16 years diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) between 1988 and 2011 in the prospective EPIMAD population-based registry were followed until 2013. Every TE occurring during the follow-up period was included. RESULTS: A total of 1,344 patients were included: 1,007 with CD and 337 with UC, and a median diagnosis age of 14.3 years. After a median follow-up of 8.3 years, 2 (0.15 %) ATE and 15 (1.1 %) VTE occurred at median age of 20.4 years. The global incidence rate of thromboembolic events was 1.32 per 1000 person-years. Periods of active disease (HR=8.4, p = 0.0002), the 3-month-period following surgery (HR=16.4, p = 0.0002) and hospitalization (HR=21.7, p < 0.0001) were found to be associated with an increased risk of VTE. A lower rate of VTE was found in patients treated with 5-aminosalicylates (HR=0.1, p = 0.002). CONCLUSION: The risk of TE was low in this population. VTE were strongly associated with active disease, surgery and hospitalization.

Grégoire, S., Lachance, L., & Richer, L. (2016). La présence attentive, mindfulness. État des connaissances empiriques et pratiques. Presses de l’Université du Québec. Un article de la revue Revue québécoise de psychologie (LA MENTALISATION : AU COEUR DE LA PRATIQUE CLINIQUE ET DE LA SANTÉ MENTALE) diffusée par la plateforme Érudit.

This paper is a first empirical foray in the debate concerning mandatory bilingualism for Supreme Court judges in Canada. The paper summarizes the main arguments, discusses the framing of bilingualism as a “legal” or an “identity” requirement, and uses empirical data to assess whether unilingualism has had an impact on four dimensions of the decision-making process at the Supreme Court of Canada: panel composition, assertiveness, individual caseloads and deference towards lower courts by unilingual and bilingual judges. Our results suggest that there is a correlation between the fluency in French and the first three elements but that there is no difference in the level of deference across linguistic groups towards francophone lower courts. Even if the paper is exploratory in nature and warrants further research, the general picture that emerges is that language proficiency superimposes itself as another kind of legal specialization in the inner-working of the Court.

Le propos de cet article est d'ébaucher une problématique de l'intolérance et de l'oppression par la voie de deux objectifs : soulever la question des causes de ces phénomènes et essayer de déterminer s'il existe une oppression fondamentale. Un tour d'horizon des causes nous apprend très vite que les « explications » fournies décrivent beaucoup plus un enchaînement qu'elles ne remontent aux origines. Déterminer la part de la « nature humaine » dans les rapports de domination, par exemple, est un défi insoluble. Théoriciens et gens d'action gagnent donc à se pencher sur le comment plutôt que sur le pourquoi de l'intolérance. En ce sens, on peut se demander s'il est une oppression plus fondamentale que les autres. Et en effet, parce qu'on ne peut en changer, celle qui porte sur l'identité est plus essentielle que celle qui s'articule autour des manières de penser ou d'agir. Or, l'analyse comparée permet de conclure que, parce qu'ils décuplent tous les autres, les rapports de domination fondés sur le sexe sont, non pas plus fondamentaux, mais plus universels que ceux qui reposent sur l'âge, la classe sociale, la condition physique ou mentale, l'ethnie / « race » ou l'orientation sexuelle.

Mobile ad hoc networks (MANETs) are infrastructureless and can be set up temporarily. They can host a wide range of conferencing applications, such as audio/video conferencing. Decentralised versions of session initiation protocol (SIP) fit the lightweight and scalability requirements needed for MANETs. Security in decentralised SIP has not yet been addressed. This paper presents an authentication scheme for decentralised SIP. The scheme allows the members of a decentralised SIP-based conference to securely perform SIP operations. The scheme employs identity-based signatures cryptography. The practicality and effectiveness of the scheme is illustrated using a working prototype.

Mobile ad hoc networks (MANETs) are infrastructureless and can be set up temporarily. They can host a wide range of conferencing applications, such as audio/video conferencing. Decentralised versions of session initiation protocol (SIP) fit the lightweight and scalability requirements needed for MANETs. Security in decentralised SIP has not yet been addressed. This paper presents an authentication scheme for decentralised SIP. The scheme allows the members of a decentralised SIP-based conference to securely perform SIP operations. The scheme employs identity-based signatures cryptography. The practicality and effectiveness of the scheme is illustrated using a working prototype.