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Faster Exploration of Some Temporal Graphs
(Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing, 2022-04-01) Adamson, Duncan; Gusev, Vladimir V.; Malyshev, Dmitriy; Zamaraev, Viktor; Aspnes, James; Michail, Othon
A temporal graph G = (G1, G2,..., GT ) is a graph represented by a sequence of T graphs over a common set of vertices, such that at the ith time step only the edge set Ei is active. The temporal graph exploration problem asks for a shortest temporal walk on some temporal graph visiting every vertex. We show that temporal graphs with n vertices can be explored in O(kn1.5 log n) days if the underlying graph has treewidth k and in O(n1.75 log n) days if the underlying graph is planar. Furthermore, we show that any temporal graph whose underlying graph is a cycle with k chords can be explored in at most 6kn days. Finally, we demonstrate that there are temporal realisations of sub cubic planar graphs that cannot be explored faster than in Ω(n log n) days. All these improve best known results in the literature.
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Improving adherence to a web-based cognitive-behavioural therapy program for social anxiety with group sessions : A randomised control trial
(2022-04) Sigurðardóttir, Signý; Helgadóttir, Fjóla Dögg; Menzies, Rachel E.; Sighvatsson, Magnús Blöndahl; Menzies, Ross G.
Individuals with social anxiety disorder (SAD) commonly receive non-evidence based, ineffective treatments. Cognitive behaviour therapy (CBT) has been demonstrated to be the gold standard treatment for treating SAD. Scalable web-based CBT programs ensure evidence-based treatment procedures, but low treatment adherence remains problematic. This study aimed to test whether adding group sessions to a fully automated web-based CBT program, Overcome Social Anxiety (OSA), would increase treatment adherence. A total of 69 participants were provided access to a web-based program, and randomly allocated to three conditions: 1) An experimental condition involving an addition of three online group psychoeducation sessions; 2) a placebo condition involving an addition of three online progressive muscle relaxation (PMR) group sessions, or 3) a control condition where participants did not receive group sessions. Adherence was operationalised as number of OSA modules completed. Treatment adherence significantly differed between the conditions. On average, participants assigned to the placebo condition completed significantly more of the program compared to those in the control condition. Further, all conditions produced a significant improvement in BFNE and QOLS. No significant difference in treatment efficacy was found between groups on the SIAS, BFNE or QOLS. The current results indicate PMR can improve treatment adherence for scalable social anxiety interventions.
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Pharmacological and non-pharmacological interventions for adults with ADHD : Protocol for a systematic review and network meta-analysis
(2022-03-11) Cortese, Samuele; Del Giovane, Cinzia; Chamberlain, Samuel; Philipsen, Alexandra; Young, Susan; Bilbow, Andrea; Cipriani, Andrea
Introduction It is unclear how pharmacological and non-pharmacological interventions compare with each other in terms of efficacy and tolerability for core symptoms and additional problems in adults with attention-deficit/hyperactivity disorder (ADHD). We aim to conduct the first network meta-analysis (NMA) comparing pharmacological and non-pharmacological interventions (or their combinations) in adults with ADHD. Methods and analysis We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for NMAs. We will search a broad set of electronic databases/registries and contact drug companies and experts in the field to retrieve published and unpublished randomised controlled trials (RCTs) (parallel or cross-over) of medications (either licensed or unlicensed) and any non-pharmacological intervention in adults (≥18 years) with ADHD. Primary outcomes will be: (1) change in severity of ADHD core symptoms, and (2) acceptability (all-cause discontinuation). Secondary outcomes will include tolerability (drop-out due to side effects) and change in the severity of emotional dysregulation, executive dysfunctions and quality of life. The risk of bias in each individual RCT included in the NMA will be assessed using the Cochrane Risk of Bias tool-version 2. We will evaluate the transitivity assumption comparing the distribution of possible effect modifiers across treatment comparisons. We will perform Bayesian NMA for each outcome with random-effects model in OpenBUGS. Pooled estimates of NMA will be obtained using the Markov Chains Monte Carlo method. We will judge the credibility in the evidence derived from the NMA using the CINeMA tool (which includes assessment of publication bias). We will conduct a series of sensitivity analyses to assess the robustness of the findings. Ethics and dissemination As this is the protocol for an aggregate-data level NMA, ethical approval will not be required. Results will be disseminated at national/international conferences and in peer-reviewed journals. PROSPERO registration number CRD42021265576.
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Population-scale detection of non-reference sequence variants using colored de Bruijn graphs
(2022-02-01) Krannich, Thomas; Timothy, W.; Niehus, Sebastian; Holley, Guillaume; Halldorsson, Bjarni V.; Kehr, Birte; Department of Engineering
Motivation: With the increasing throughput of sequencing technologies, structural variant (SV) detection has become possible across tens of thousands of genomes. Non-reference sequence (NRS) variants have drawn less attention compared with other types of SVs due to the computational complexity of detecting them. When using shortread data, the detection of NRS variants inevitably involves a de novo assembly which requires high-quality sequence data at high coverage. Previous studies have demonstrated how sequence data of multiple genomes can be combined for the reliable detection of NRS variants. However, the algorithms proposed in these studies have limited scalability to larger sets of genomes. Results: We introduce PopIns2, a tool to discover and characterize NRS variants in many genomes, which scales to considerably larger numbers of genomes than its predecessor PopIns. In this article, we briefly outline the PopIns2 workflow and highlight our novel algorithmic contributions. We developed an entirely new approach for merging contig assemblies of unaligned reads from many genomes into a single set of NRS using a colored de Bruijn graph. Our tests on simulated data indicate that the new merging algorithm ranks among the best approaches in terms of quality and reliability and that PopIns2 shows the best precision for a growing number of genomes processed. Results on the Polaris Diversity Cohort and a set of 1000 Icelandic human genomes demonstrate unmatched scalability for the application on population-scale datasets.
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Numerical Simulation of the Response of Concrete Structural Elements Containing a Self-Healing Agent
(2022-02-01) Zhelyazov, Todor
Self-healing of a crack is a relatively novel technique allowing for the partial recovery of the initial mechanical characteristics of a structural element after some period of exploitation. By a widely accepted convention, self-healing is either autogenous or autonomous. The former is a mechanism inherent for cementitious composites (in particular—concrete), while the latter is an engineered process. Both autogenous and engineered healing have recently been the object of numerous studies. Despite the large amount of research work being carried out, the potential of this technique has not yet been fully realized. The article focuses on the modeling and the finite element simulation of the recovery of the initial material properties resulting from the sealing of cracks. The employed numerical procedure uses a constitutive relation for concrete based on the continuum damage mechanics. It captures both the strain-softening and the inverse process—the crack healing. Finite element simulations of benchmark cases illustrate the effect of self-healing. The numerically obtained constitutive relations for specimens with and without a healing agent are compared.

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