465 research outputs found

    The diameter of the world wide web

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    Despite its increasing role in communication, the world wide web remains the least controlled medium: any individual or institution can create websites with unrestricted number of documents and links. While great efforts are made to map and characterize the Internet's infrastructure, little is known about the topology of the web. Here we take a first step to fill this gap: we use local connectivity measurements to construct a topological model of the world wide web, allowing us to explore and characterize its large scale properties.Comment: 5 pages, 1 figure, updated with most recent results on the size of the ww

    Whole genome sequencing for the genetic diagnosis of heterogenous dystonia phenotypes

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    Introduction: Dystonia is a clinically and genetically heterogeneous disorder and a genetic cause is often difficult to elucidate. This is the first study to use whole genome sequencing (WGS) to investigate dystonia in a large sample of affected individuals. Methods: WGS was performed on 111 probands with heterogenous dystonia phenotypes. We performed analysis for coding and non-coding variants, copy number variants (CNVs), and structural variants (SVs). We assessed for an association between dystonia and 10 known dystonia risk variants. Results: A genetic diagnosis was obtained for 11.7% (13/111) of individuals. We found that a genetic diagnosis was more likely in those with an earlier age at onset, younger age at testing, and a combined dystonia phenotype. We identified pathogenic/likely-pathogenic variants in ADCY5 (n = 1), ATM (n = 1), GNAL (n = 2), GLB1 (n = 1), KMT2B (n = 2), PRKN (n = 2), PRRT2 (n = 1), SGCE (n = 2), and THAP1 (n = 1). CNVs were detected in 3 individuals. We found an association between the known risk variant ARSG rs11655081 and dystonia (p = 0.003). Conclusion: A genetic diagnosis was found in 11.7% of individuals with dystonia. The diagnostic yield was higher in those with an earlier age of onset, younger age at testing, and a combined dystonia phenotype. WGS may be particularly relevant for dystonia given that it allows for the detection of CNVs, which accounted for 23% of the genetically diagnosed cases. © 2019 The Author

    Unresolved issues and new challenges in teaching English to young learners:the case of South Korea

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    The introduction of languages, especially English, into the primary curriculum around the world has been one of the major language-in-education policy developments in recent years. In countries where English has been compulsory for a number of years, the question arises as to what extent the numerous and well-documented challenges faced by the initial implementation of early language learning policies have been overcome and whether new challenges have arisen as policies have become consolidated. This article therefore focuses on South Korea, where English has been compulsory in primary school since 1997. The issues raised by the introduction of English into the primary curriculum are reviewed and the current situation in South Korea is investigated. The results of a mixed methods study using survey data from 125 Korean primary school teachers, together with data from a small-scale case study of one teacher are presented. The study shows that, while some of the initial problems caused by the introduction of early language learning appear to have been addressed, other challenges persist. Moreover, the data reveal the emergence of a number of new challenges faced by primary school teachers of English as they seek to implement government policy

    Simplified Models for LHC New Physics Searches

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    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the "Topologies for Early LHC Searches" workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first ~50-500 pb-1 of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.Comment: 40 pages, 2 figures. This document is the official summary of results from "Topologies for Early LHC Searches" workshop (SLAC, September 2010). Supplementary material can be found at http://lhcnewphysics.or

    Decrease in Aβ42 predicts dopa-resistant gait progression in early Parkinson disease

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    Objective: This prospective observational study investigates the role of CSF biomarkers in predicting progression of dopa-resistant gait impairments in Parkinson disease (PD) in the first 36 months from diagnosis. Methods: Quantitative gait analysis was carried out longitudinally using an instrumented walkway (GAITRite) in 108 people with PD and 130 age-matched controls. A subgroup of 44 people with PD underwent lumbar puncture from which a battery of CSF biomarkers was measured: β-amyloid 1-42 and 1-40 (Aβ42 and Aβ40), total and phosphorylated tau protein (t-tau/p-tau181), and α-synuclein (αSyn). Linear mixed models examined the association between CSF and dopa-resistant gait characteristics (defined as substantial progression despite optimal medication). Results: Low baseline CSF Aβ42, and to a lesser extend Aβ40, predicted decline in gait characteristics in the first 3 years following diagnosis, independently explaining up to 12% of progression of step time variability (single task) and step length variability (dual-task). Interestingly, these findings were independent of age and cognition. Conclusions: These findings implicate underlying amyloid pathology in neural networks involved in locomotor control. Results suggest that disturbed Aβ metabolism may be a biomarker for dopa-resistant gait impairments in early PD. Our findings raise interesting questions regarding therapeutic interventions such as compounds or molecules aimed at reducing amyloid burden to mitigate gait disturbance in early PD and potentially falls risk. Finally, progression of discrete gait characteristics suggests they may have potential as clinical biomarkers of pathology and disease progression

    Participation of Children with Disabilities in Taiwan: The Gap between Independence and Frequency

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    BackgroundIndependence and frequency are two distinct dimensions of participation in daily life. The gap between independence and frequency may reflect the role of the environment on participation, but this distinction has not been fully explored.MethodsA total of 18,119 parents or primary caregivers of children with disabilities aged 6.0-17.9 years were interviewed in a cross-sectional nationwide survey with the Functioning Scale of the Disability Evaluation System - Child version (FUNDES-Child). A section consisting of 20 items measured the children’s daily participation in 4 environmental settings: home, neighborhood/community, school, and home/community. Higher independence and frequency restriction scores indicated greater limitation of participation in daily activities. Scores for independence, frequency and independence-frequency gaps were examined across ages along with trend analysis. ANOVA was used to compare the gaps across settings and diagnoses for children with mild levels of severity of impairment.FindingsA negative independence-frequency gap (restriction of frequency was greater than that of independence) was found for children with mild to severe levels of impairment. A positive gap (restriction of independence was greater than that of frequency) was found for children with profound levels of severity. The gaps became wider with age in most settings of children with mild impairment and different diagnoses. Widest negative gaps were found for the neighborhood/community settings than for the other three settings for children with mild to severe impairment.ConclusionsChildren’s participation and independence-frequency gaps depend not only on the severity of their impairments or diagnoses, but also on their age, the setting and the support provided by their environment. In Taiwan, more frequency restrictions than ability restrictions were found for children with mild to moderate severity, especially in the neighborhood/community setting, and increased with age. Further identification of environmental opportunities that positively impact frequency of participation is needed

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
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