3,842 research outputs found

    Layered Social Network Analysis Reveals Complex Relationships in Kindergarteners.

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    The interplay between individuals forms building blocks for social structure. Here, we examine the structure of behavioral interactions among kindergarten classroom with a hierarchy-neutral approach to examine all possible underlying patterns in the formation of layered networks of "reciprocal" interactions. To understand how these layers are coordinated, we used a layered motif approach. Our dual layered motif analysis can therefore be thought of as the dynamics of smaller groups that tile to create the group structure, or alternatively they provide information on what the average child would do in a given local social environment. When we examine the regulated motifs in layered networks, we find that transitivity is at least partially involved in the formation of these layered network structures. We also found complex combinations of the expected reciprocal interactions. The mechanisms used to understand social networks of kindergarten children here are also applicable on a more general scale to any group of individuals where interactions and identities can be readily observed and scored

    A new species of stalked crinoid (Echinodermata) of possible Late Silurian age from central Newfoundland

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    A new fossil locality within a sequence previously assigned to the Middle Ordovician Baie D'Espoir Group in south-central Newfoundland contains fragmented crinoid columnals and brachiopods. Distinctive, pentastellate crinoid columnals, similar to those assigned to the monobathrid camerate Hexacrinites Austin and Austin by Russian authors, are named Hexacrinites? Pentastellatus n. sp. Nodal(?) columnals of this species have a circular, depressed articular facet, with a conical to bowl-like crenularium, a depressed, circular areola, a raised perilumen and a short, slender axial canal of pentagonal section. The oldest Hexacrinites sensu stricto are Late Silurian, suggesting that the fossiliferous strata have been incorrectly assigned to the Ordovician. Cross-sections of brachiopods from the same locality include an example that resembles several Early Silurian to Late Devonian pentameroid genera including Brooksina Kirk, 1922. Correlation with Late Silurian, bivalve-bearing strata SO km to the northeast would indicate that a major unconformity may occur above the fossiliferous Early and Middle Ordovician strata and the Early Ordovician ophiolite complexes. RÉSUMÉ Un nouvel emplacement de fossiles à I'intérieur d'une sequence auparavant attribute au groupe de l'Ordovicien moyen de Baie d'Espoir dans le centre-sud de Terre-Neuve renferme des fragments de columnales et de brachiopodes de crinoldes. Des columnales de crinoldes pentaétoilées caractéristiqucs, semblables à celles attributées à l’Hexacrinites Austin and Austin à loges monobathrides par des auteurs russes, sont baptisées nouvelle espèce pentastellatus d'Hexacrinites?. Les columnales nodales(?) de cette espèce sont pourvues d'une facette articulaire renfoncée et circulaire munie d'un crenularium allant de conique à bombé, d'une aréole circulaire renfoncie, d'un périlumen surélevé et d'un canal axial mince et court de section pentagonalc. Les plus anciens Hexacrinites, au sens strict, remontent au Silurien supérieur, ce qui permet de supposer qu'on a incorrectement attribué la strate fossilifère à l'Ordovicien. Des iéchantillons représentatifs de brachiopodes du même emplacement comprennent un exemple qui ressemble à plusieurs genres de pentaméroides datant du Silurien inférieur au Dévonien supérieur, notamment le Brooksina Kirk, 1922. Leur corrélation avec des strates renfermant des bivalves du Silurien supérieur à 50 km au nord-cst signale qu'une discordance importantc pourrait se présenter au-dessus des strates fossiliferes de l'Ordovicien inférieur ou moyen de même que des complexes d'ophiolites de l'Ordovicien inférieur. [Traduit par la rédaction

    Bilateral symmetry breaking in a nonlinear Fabry-Perot cavity exhibiting optical tristability

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    We show the existence of a region in the parameter space that defines the field dynamics in a Fabry-Perot cylindrical cavity, where three output stable stationary states of the light are possible for a given localized incident field. Two of these states do not preserve the bilateral (i.e. left-right) symmetry of the entire system. These broken-symmetry states are the high-transmission nonlinear modes of the system. We also discuss how to excite these states.Comment: 5 pages, 5 figure

    Synchronization in small-world systems

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    We quantify the dynamical implications of the small-world phenomenon. We consider the generic synchronization of oscillator networks of arbitrary topology, and link the linear stability of the synchronous state to an algebraic condition of the Laplacian of the graph. We show numerically that the addition of random shortcuts produces improved network synchronizability. Further, we use a perturbation analysis to place the synchronization threshold in relation to the boundaries of the small-world region. Our results also show that small-worlds synchronize as efficiently as random graphs and hypercubes, and more so than standard constructive graphs

    Low Temperature Anomaly in Mesoscopic Kondo Wires

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    We report the observation of an anomalous magnetoresistance in extremely dilute quasi-one-dimensional AuFe wires at low temperatures, along with a hysteretic background at low fields. The Kondo resistivity does not show the unitarity limit down to the lowest temperature, implying uncompensated spin states. We suggest that the anomalous magnetoresistance may be understood as the interference correction from the accumulation of geometric phase in the conduction electron wave function around the localized impurity spin.Comment: Four pages, five figure

    Knight Shift Anomalies in Heavy Electron Materials

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    We calculate non-linear Knight Shift KK vs. susceptibility χ\chi anomalies for Ce ions possessing local moments in metals. The ions are modeled with the Anderson Hamiltonian and studied within the non-crossing approximation (NCA). The Kvs.χK-vs.- \chi non-linearity diminishes with decreasing Kondo temperature T0T_0 and nuclear spin- local moment separation. Treating the Ce ions as an incoherent array in CeSn3_3, we find excellent agreement with the observed Sn K(T)K(T) data.Comment: 4 pages, Revtex, 3 figures available upon request from [email protected]

    Adolescent chronic illness : a qualitative study of psychosocial adjustment

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    Introduction: The purpose of this study was to investigate the psychosocial issues facing young people living with a chronic medical condition. Materials and Methods: Subjects were young people with a range of medical conditions who were on a waiting list to participate in the Chronic Illness Peer Support programme at the Centre for Adolescent Health, Royal Children\u27s Hospital, Melbourne, Australia. Young people agreed to in-depth interviews which were taped and transcribed. Thematic analysis was undertaken by two researchers working independently. Results: Thirty-five young people were interviewed. Thematic analysis revealed five broad themes: control (in control, under control, out of control); emotional reactions (happiness, frustration, anger, sadness, anxiety); acceptance (of illness, of others, of self); coping strategies, and; a search for meaning. The importance of social connections was emphasised. While illustrating the difficulties of managing a chronic medical condition during adolescence, a generally positive message emerges about these young people. Conclusions: Many young people with chronic illness appear relatively resilient in the face of the adjustment challenges presented by their illness. Interventions that allow a young person to explore meaning, build self-esteem, and acceptance through positive social connections are likely to improve adjustment outcomes in this group.<br /

    Subduction beneath Laurentia modified the eastern North American cratonic edge : Evidence from P wave and S wave tomography

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    Funding Information: NERC Doctoral Training Partnership: Science and Solutions for a Changing Planet and Leverhulme Trust Acknowledgments A.B. is funded by the NERC Doctoral Training Partnership: Science and Solutions for a Changing Planet. I.B. is funded by the Leverhulme Trust. F.D. acknowledges funding from NSERC through their Discovery grants and Canada Research Chairs program. We thank J. VanDecar for use of his tomographic inversion and MCCC codes. SAC [Helffrich et al., 2013] and GMT [Wessel and Smith, 1995] software were also used to process seismic data obtained from the IRIS DMC and from the Canadian National Data Centre (Natural Resources Canada). A digital supplement is also available to download containing models and the processed relative arrival‐time data set, additional information is available from A.B. (email: [email protected]). Discussing the implications of our tomographic results with S. Goes and A. Hynes provided great motivation for this manuscript. Two anonymous reviewers helped clarify our interpretations.Peer reviewedPublisher PD
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