30 research outputs found

    Fractional Hamiltonian Monodromy from a Gauss-Manin Monodromy

    Full text link
    Fractional Hamiltonian Monodromy is a generalization of the notion of Hamiltonian Monodromy, recently introduced by N. N. Nekhoroshev, D. A. Sadovskii and B. I. Zhilinskii for energy-momentum maps whose image has a particular type of non-isolated singularities. In this paper, we analyze the notion of Fractional Hamiltonian Monodromy in terms of the Gauss-Manin Monodromy of a Riemann surface constructed from the energy-momentum map and associated to a loop in complex space which bypasses the line of singularities. We also prove some propositions on Fractional Hamiltonian Monodromy for 1:-n and m:-n resonant systems.Comment: 39 pages, 24 figures. submitted to J. Math. Phy

    Evaluation of a French parent-training program in young children with autism spectrum disorder = Évaluation d'un programme francophone de formation aux habiletĂ©s parentales dans le cadre des troubles du spectre de l'autisme auprĂšs d'un groupe pilote

    Get PDF
    Parent training programs (PTs) in young children with autism spectrum disorders (ASDs) are known to reduce parenting stress and improve child's behavior and parent-child interactions. Few PTs are available to French speaking families. In order to provide them with this type of intervention, we developed a French parent-training program of 12 bimonthly sessions and three individual home visits based on applied behavior analysis. The purpose of this study is to evaluate the social validity and efficacy of this new PT on eighteen parents who have a child with ASD and developmental delay. For 16 parents, the PT was considered effective, the objectives targeted important and the strategies learned acceptable for use with children. They have significantly improved their knowledge in ASD and behavioral intervention strategies and their children's socialization skills, and reduce their parental stress. This new French PT program seems to be a promising intervention. RĂ©sumĂ©. Objectifs : Le programme intitulĂ© « l’ABC du comportement de l’enfant ayant un TSA : des parents en action ! » est un programme psychoĂ©ducatif de 12 sĂ©ances de 2 heures et de 3 visites Ă  domicile destinĂ© aux familles de jeunes enfants ĂągĂ©s jusqu’à 7 ans et ayant un trouble du spectre de l’autisme (TSA) avec retard de dĂ©veloppement. Ce programme de formation aux habiletĂ©s parentales (PFHP), basĂ© sur l’analyse appliquĂ©e du comportement, a Ă©tĂ© dĂ©veloppĂ© en rĂ©ponse au besoin de formation des parents issus d’une population francophone pour faire face au stress qu’engendrent les difficultĂ©s de comportement de leur enfant en environnement familial. Cette nouvelle intervention, offerte en groupe, a Ă©tĂ© proposĂ© Ă  30 parents sur un premier site francophone. Cette Ă©tude vise Ă  Ă©valuer la validitĂ© sociale et l’efficacitĂ© de ce nouveau PFHP. MĂ©thode : Ce PFHP a Ă©tĂ© proposĂ© Ă  trois groupes consĂ©cutifs de 4 à 6 familles. Il a Ă©tĂ© Ă©valuĂ© auprĂšs de 18 parents et 10 enfants. Pour Ă©valuer la validitĂ© sociale du programme, les parents ont rempli des questionnaires sur la signification sociale des objectifs ciblĂ©s, l’acceptabilitĂ© des procĂ©dures utilisĂ©es et l’importance sociale des effets obtenus. L’efficacitĂ© du PFHP est Ă©valuĂ©e au travers de questionnaires remplis en prĂ©-intervention, post-intervention et en suivi trois mois aprĂšs la fin du programme. Ces questionnaires portent sur les connaissances des parents, le niveau de stress parental, les symptĂŽmes dĂ©pressifs et les comportements de l’enfant. RĂ©sultats : Parmi les 18 participants, 16 parents sont satisfaits de l’intervention. Ils considĂšrent les objectifs ciblĂ©s comme importants, les procĂ©dures transmises comme acceptables Ă  utiliser et les compĂ©tences parentales dĂ©veloppĂ©es comme satisfaisantes. Le PFHP a Ă©tĂ© efficace tant au niveau des problĂ©matiques parentales que des acquisitions des enfants. Une augmentation des connaissances et des pratiques Ă©ducatives est observĂ©e avec une diminution du stress parental. Une amĂ©lioration des compĂ©tences sociales des enfants est Ă©galement constatĂ©e. Le PFHP n’a cependant pas Ă©tĂ© bĂ©nĂ©fique pour une famille dont la situation s’est dĂ©tĂ©riorĂ©e. Conclusion : Ce PFHP est une intervention prometteuse pour rĂ©pondre aux besoins de formation des familles des jeunes enfants avec un TSA et un retard de dĂ©veloppement. Il reste toutefois insuffisant pour rĂ©pondre aux besoins des parents en grande dĂ©tresse. Un manuel de ce PFHP a Ă©tĂ© Ă©laborĂ© afin de le proposer Ă  un plus grand nombre de parents sur diffĂ©rents sites francophones pour valider les effets du programme

    On the Number of Zeros of Abelian Integrals: A Constructive Solution of the Infinitesimal Hilbert Sixteenth Problem

    Full text link
    We prove that the number of limit cycles generated by a small non-conservative perturbation of a Hamiltonian polynomial vector field on the plane, is bounded by a double exponential of the degree of the fields. This solves the long-standing tangential Hilbert 16th problem. The proof uses only the fact that Abelian integrals of a given degree are horizontal sections of a regular flat meromorphic connection (Gauss-Manin connection) with a quasiunipotent monodromy group.Comment: Final revisio

    Influence of halloysite nanotubes on physical and mechanical properties of cellulose fibres reinforced vinyl ester composites

    Get PDF
    Natural fibres are generally added to polymer matrix composites to produce materials with the desirable mechanical properties of higher specific strength and higher specific modulus while at the same time to maintain a low density and low cost. The physical and mechanical properties of polymer composites can be enhanced through the addition of nanofillers such as halloysite nanotubes. This article describes the fabrication of vinyl ester eco-composites and eco-nanocomposites and characterizes these samples in terms of water absorption, mechanical and thermal properties. Weight gain test and Fourier transform infrared analysis indicated that 5% halloysite nanotube addition gave favourable reduction in the water absorption and increased the fibre–matrix adhesion leading to improved strength properties in the eco-nanocomposites. However, halloysite nanotube addition resulted in reduced toughness but improved thermal stability

    Peer Review : Local and Global Processing in Blind and Sighted Children in a naming and drawing task

    Get PDF

    A New Efficient Authenticated and Key Agreement Scheme for SIP Using Digital Signature Algorithm on Elliptic Curves

    No full text
    Voice over Internet Protocol (VoIP) has been recently one of the more popular applications in Internet technology. It benefits lower cost of equipment, operation, and better integration with data applications than voice communications over telephone networks. However, the voice packets delivered over the Internet are not protected. The session initiation protocol (SIP) is widely used signaling protocol that controls communications on the Internet, typically using hypertext transport protocol (HTTP) digest authentication, which is vulnerable to many forms of attacks. This paper proposes a new secure authentication and key agreement scheme based on Digital Signature Algorithm (DSA) and Elliptic Curve Cryptography (ECC) named (ECDSA). Security analysis demonstrates that the proposed scheme can resist various attacks and it can be applied to authenticate the users with different SIP domains

    Kausale ReprÀsentation bei Morbus-Crohn-Patienten: Gibt es einen Zusammenhang zwischen psychologischer Belastung und klinischer AktivitÀt?

    Get PDF
    Objectives: Because of the fluctuating and occasional character of Crohn's disease (CD), patients have to cope with a changeable condition of health. Personal perceived control is known to be an important element of adaptation to their medical condition. The objectives of this work are to determine if perceived personal control is predictive of the clinical activity of the disease and of psychological distress (depression, anxiety). Methods: The Hospital Anxiety Depression Scale (HADS), the causal dimension scale and the Clinical Global Impression (CGI; assessing perceived severity) were administered to 160 patients affected by Crohn's disease. Indicators of inflammation (CRP), disease duration and clinical activity of the disease were also asessed. Results: Globally, CD patients perceive their disease as being personally neither controllable nor uncontrollable. Whereas psychological distress is significantly higher when the disease is active, the relationship between the variables appears complex. The feeling of personal control is explained by the clinical activity of the disease (p=.0001) and by the perception that CD is unstable (p<.00001) and globally impacts the life of patients (p=.001). Nevertheless perception of personal control does not explain the clinical activity of the disease. Finally, psychological distress is explained by the perception that the medical team is unable to control the disease (p=.00001) and by the global consequences of the disease on life (p<.005). Conclusions: Psychological treatments should take these dimensions into account so as to improve the well-being and medical conditions of patients.Zielsetzung: Aufgrund des fluktuierenden Charakters des Morbus Crohn (Crohn's disease, (CD)) mĂŒssen Patienten mit der VerĂ€nderlichkeit ihres Gesundheitszustandes zurechtkommen. Die wahrgenommene, persönliche Kontrollierbarkeit ist ein wichtiges Element der AnpassungsfĂ€higkeit an die Herausforderungen des Krankheitsbildes. In dieser Arbeit wird untersucht, ob wahrgenommene Kontrolle als PrĂ€diktor klinischer AktivitĂ€t der Krankheit und psychologischer Belastung (Depression, Angst) angesehen werden kann.Methode: Der HADS (Hospital Anxiety Depression Scale), die Kausale Dimensonsskala und der CGI (Clinical Global Impression, EinschĂ€tzung der wahrgenommenen Schwere) wurden an 160 CD-Patienten erhoben. EntzĂŒndungsindikatoren (CRP), Krankheitsdauer und klinische AktivitĂ€t der Krankheit wurden ebenfalls erhoben.Ergebnisse: Insgesamt scheinen die Patienten ihre Krankheit weder als persönlich ausgeprĂ€gt kontrollierbar noch unkontrollierbar zu empfinden. WĂ€hrend die psychologische Belastung bei klinisch aktivem Symptombild höher ist, erweist sich die Beziehung zwischen den Variablen als komplex. Das GefĂŒhl persönlicher Kontrolle weist einen Zusammenhang zu der klinischen AktivitĂ€t der Krankkheit auf (p=0,0001), wie auch die Wahrnehmung der StabilitĂ€t der CD (p<0,0001) und die GlobalitĂ€t des Einflusses der Krankheit auf das Leben (p=0,001). Ungeachtet dessen zeigte sich die wahrgenommene persönliche Kontrolle nicht als prĂ€diktiv fĂŒr den AktivitĂ€tsstatus der Krankheit. Schließlich zeigte sich ein Zusammenhang psychologischer Belastung mit der Wahrnehmung der Kontrollierbarkeit der Krankheit durch das medizinische Team (p=0,00001) und der GlobalitĂ€t der Krankheitsfolgen fĂŒr das Leben (p<0,005)Schlussfolgerung: Psychologische Behandlungen sollten diese Dimensionen berĂŒcksichtigen, um das Wohlbefinden und die Gesundheit der Patienten zu verbessern
    corecore