625 research outputs found

    Circumference and Pathwidth of Highly Connected Graphs

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    Birmele [J. Graph Theory, 2003] proved that every graph with circumference t has treewidth at most t-1. Under the additional assumption of 2-connectivity, such graphs have bounded pathwidth, which is a qualitatively stronger result. Birmele's theorem was extended by Birmele, Bondy and Reed [Combinatorica, 2007] who showed that every graph without k disjoint cycles of length at least t has bounded treewidth (as a function of k and t). Our main result states that, under the additional assumption of (k + 1)- connectivity, such graphs have bounded pathwidth. In fact, they have pathwidth O(t^3 + tk^2). Moreover, examples show that (k + 1)-connectivity is required for bounded pathwidth to hold. These results suggest the following general question: for which values of k and graphs H does every k-connected H-minor-free graph have bounded pathwidth? We discuss this question and provide a few observations.Comment: 11 pages, 4 figure

    Neurological approach measuring attentional variations among children with high-functioning autism spectrum disorder, sensory processing difficulties and age-matched peers, A

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    2015 Spring.Includes bibliographical references.Children with high functioning autism (HFA) and children with sensory processing difficulties (SPD) can have challenges processing auditory stimuli, which may contribute to difficulties with performance of everyday tasks. Few studies assess relationships between neurological measures with behavioral attention measures, yet the benefits of doing so are invaluable in understanding the brain and behavior connections in children who have difficulties processing sensory information. Therefore, this study focuses on examining the impact of neurological auditory processing on performance on tasks that require attention among children with HFA, SPD and typically developing (TD) controls. Participants included 20 children with HFA (mean age = 8.94 ± 2.03 years), 9 children with SPD (mean age = 6.57 ± 1.26 years), and 22 TD gender and age-matched peers (mean age = 8.46 ± 2.39 years). Groups were compared according to behavioral assessment of everyday task performance and a neurological paradigm. The Test of Everyday Attention for Children (TEA-Ch) evaluates a child's attention during tasks that correspond with three subtypes of attention, while the orientation and habituation electroencephalography (EEG) paradigm allows for sensory gating and habituation neural processing measurement and analysis. Based on the TEA-Ch scores, children in with HFA and SPD groups had significant differences with attention demands, especially in the domains of control/shift and sustained attention, when compared to the TD group. On the neurological measures, children with HFA displayed similar sensory gating abilities as compared to TD peers, including a reduction of both N1 and N2 amplitudes from tone 1 to tone 2, while children with SPD showed difficulties with sensory gating of N1 amplitudes only. Habituation analysis revealed significantly larger N2 amplitudes at tone 8 when compared to tone 2 among all groups suggesting that habituation does not occur for N2 amplitude among children in all three groups. A significant interaction occurred between tone and group for N1 amplitudes of children with SPD and the control group suggesting that the children in the control group did not habituate but the children in the SPD group did habituate. Analysis of N1 and N2 amplitude responses to tone 1 in a train without a deviant resulted in no significant differences among all three groups. However, while no differences were found between groups for the first tone, for N1 both HFA and TD groups had significant larger amplitude to the deviant tone in the 5th position, as compared to amplitude of brain response to the tone prior to the deviant. Children with SPD also had significantly larger N1 and N2 amplitudes to the deviant tones in the 4th and 5th positions, when compared to the amplitudes to the tone prior to the deviant. SPD and TD groups had an interaction at N2 amplitudes in the train with the deviant in the 4th positions. The SPD group displayed increased amplitudes at N2 to the deviant while TD decreased N2 amplitudes to the deviant. Regression analysis was conducted to assess relationships between the subtests of the TEA-Ch data and the neurological auditory processing phenomena. For the TD group this analysis revealed a strong relationship between attentional control/shift tasks and N2 amplitudes at tone 1 in the series without a deviant. For children with HFA, there was a significant relationship between attentional control/shift tasks and N1 amplitudes at tone 1 in the train without a deviant. Children with SPD also had a relationship between selective attention measures and N1 amplitudes at tone 1 in the train without a deviant. Results suggest that children with HFA, SPD and TD controls have distinct neuronal profiles related to attention. A better understanding of these group differences may help to elucidate the differential impact of auditory processing capacities on task performance in children with disabilities. This knowledge may inform how occupational therapists select therapeutic approaches, scaffold attention demands, and stimulate the adaptive response during interventions focused toward improving everyday task performance

    Navigating the Rough Waters of Change : The New OhioLINK ETD Service

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    On January 14, 2013, the OhioLINK community was informed that the Electronic Theses & Dissertations (ETD) service was down for emergency maintenance. Few in the community could have predicted that single event would trigger a tidal wave of changes that ultimately resulted in a complete system rebuild. Panel participants will discuss the situation from their perspectives as OhioLINK ETD stakeholders. Implementing a new consortial system is a tricky undertaking even with adequate time to plan for the development. What additional pressures come into play when an emergency necessitates rapid development and implementation? What is the impact of changing to a new system in the middle of the academic year during the weeks leading up to the community’s busiest ETD season? How will the hundreds of papers submitted but not approved before the system went down be handled? What adjustments will stakeholders need to make in the short term to realize the long term benefit of an improved consortial ETD submission and approval system? What improvements have been realized with the new system? Communication is vitally important during times of transition. What successes and/or failures of communication can be identified in hindsight? How would the situation be different if the Ohio ETD community had not gathered in the summer of 2012 to discuss their needs and desires for a better system that provided a foundation for functional requirements? What are these new functions and how are they working so far? What future enhancements are on the horizon for the new system? The panelists will discuss these and other issues in a session designed for active audience participation

    Towards a Practical Behavior Analytic Multitiered Consultation Model for Early Childhood Educators

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    Early childhood educators are in a critical position to support young children’s social-emotional, behavioral, and learning development, which can be accomplished through consistent use of evidence-based practices delivered in day-to-day interactions. However, early childhood educators may require support for implementing evidence-based practices. The purpose of this paper is to introduce a novel form of behavioral consultation for early childhood educators. Specifically, a behavior analytic multitiered consultation model in which implementation supports become increasingly more intensive is described. Rationale, implementation, evidence-base, and implications for practice and research are described. Finally, this paper concludes with an empirical case study to illustrate this model’s implementation. This paper is also meant to serve as a call-to-action for researchers and practitioners to replicate this consultation model

    Determinants of physiological uptake of 18F-fluorodeoxyglucose in palatine tonsils

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    To determine the extent of physiological variation of uptake of 18F-flurodeoxyglucose (FDG) within palatine tonsils. To define normal limits for side-to-side variation and characterize factors affecting tonsillar uptake of FDG.Over a period of 16 weeks 299 adult patients at low risk for head and neck pathology, attending our center for FDG positron emission tomography/computed tomography (PET/CT) scans were identified. The maximum standardized uptake value (SUVmax) was recorded for each palatine tonsil. For each patient age, gender, smoking status, scan indication and prior tonsillectomy status as well as weather conditions were noted.There was a wide variation in palatine tonsil FDG uptake with SUVmax values between 1.3 and 11.4 recorded. There was a strong left to right correlation for tonsillar FDG uptake within each patient (P < .01). The right palatine tonsil showed increased FDG uptake (4.63) compared to the left (4.47) (P < .01). In multivariate analysis, gender, scan indication, and prevailing weather had no significant impact of tonsillar FDG uptake. Lower tonsillar uptake was seen in patients with a prior history of tonsillectomy (4.13) than those without this history (4.64) (P < .01). Decreasing tonsillar FDG uptake was seen with advancing age (P < .01). Significantly lower uptake was seen in current smokers (SUVmax 4.2) than nonsmokers (SUV 4.9) (P = .03).Uptake of FDG in palatine tonsils is variable but shows a strong side-to-side correlation. We suggest the left/ right SUVmax ratio as a guide to normality with a first to 99th percentiles of (0.70–1.36) for use in patients not suspected to have tonsillar pathology
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