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On independent set on B1-EPG graphs [article]

Marin Bougeret, Stephane Bessy, Daniel Gonçalves, Cristophe Paul
2015 arXiv   pre-print
In this paper we consider the Maximum Independent Set problem (MIS) on B_1-EPG graphs.  ...  The study of MIS on B_1-EPG graphs has been initiated in wadsMIS where authors prove that MIS is NP-complete on B_1-EPG graphs, and provide a polynomial 4-approximation.  ...  Introduction and related work In this paper we consider the Maximum Independent Set (MIS) on B 1 -EPG graphs.  ... 
arXiv:1510.00598v1 fatcat:uu6ymc23wnep7chkymxdytuww4

A note on Helly-B1-EPG graphs

Liliana Alcón, María Pía Mazzoleni, Tanilson dos Santos
2022 Matemática contemporânea  
A clique is a set of pairwise adjacent vertices and an independent set is a set of pairwise non adjacent vertices.  ...  ■ A graph G is said to be Bipartite if its set of vertices can be partitioned into two distinct independent sets.  ... 
doi:10.21711/231766362021/rmc483 fatcat:djzsp3xrynhbtoa2kfjv2hzxe4

Computing Maximum Cliques in $$B_2$$ -EPG Graphs [chapter]

Nicolas Bousquet, Marc Heinrich
2017 Lecture Notes in Computer Science  
It generalizes a result of [Epstein et al, 2013] on B1-EPG graphs (where the representation was needed).  ...  Epstein et al. showed in 2013 that computing a maximum clique in B1-EPG graphs is polynomial.  ...  Let G be a B k -EPG graph on n vertices. There are at most (k + 1)(ω(G) − 1)n edges in G. Proof. Let G be a B k -EPG graph, and consider a representation of G.  ... 
doi:10.1007/978-3-319-68705-6_11 fatcat:ye5zj5ei45h5zl7khkxe2c66qa

Fast Open-Source Toolkit for Water T2 Mapping in the Presence of Fat From Multi-Echo Spin-Echo Acquisitions for Muscle MRI

Francesco Santini, Xeni Deligianni, Matteo Paoletti, Francesca Solazzo, Matthias Weigel, Paulo Loureiro de Sousa, Oliver Bieri, Mauro Monforte, Enzo Ricci, Giorgio Tasca, Anna Pichiecchio, Niels Bergsland
2021 Frontiers in Neurology  
The proposed software is capable of fast reconstruction thanks to extended phase graphs (EPG) simulations and dictionary matching implemented on a general-purpose graphic processing unit.  ...  The proposed reconstruction software was applied on the full datasets, and additionally to reduced number of echoes, respectively, to 8, 5, and 3, using EPG and biexponential least-squares fitting, with  ...  (14) presented a method based on an extended phase graph (EPG) fitting that addresses many of these issues.  ... 
doi:10.3389/fneur.2021.630387 pmid:33716931 pmcid:PMC7952742 fatcat:yv72rerko5f6nms62sfdy4f7kq

Graphs of Edge-Intersecting and Non-Splitting One Bend Paths in a Grid [article]

Arman Boyacı, Tınaz Ekim, Mordechai Shalom, Shmuel Zaks
2016 arXiv   pre-print
EPG) Edge Intersection Graphs of Paths in a tree (resp. in a grid) are well studied graph classes.  ...  Motivated by this result, in this work we focus on one bend ENPG graphs. We show that one bend ENPG graphs are properly included in two bend ENPG graphs.  ...  Fig. 1 : 1 (a) A B1-EPG representation of C4, (b) A B1-EPG representation of C11. Fig. 3 : 3 Regions of ∪PK and possible representations of a vertex in S for a B1-ENPG split graph S(K, S, E).  ... 
arXiv:1512.06440v2 fatcat:6jk2fyxgmnb2bb5sdfgjumeskm

Non-negative least squares computation for in vivo myelin mapping using simulated multi-echo spin-echo T2 decay data [article]

Vanessa Wiggermann, Irene M Vavasour, Shannon Kolind, Alexander L MacKay, Gunther Helms, Alexander Rauscher
2020 bioRxiv   pre-print
MWF estimates were more stable than myelin water gmT2 time across different settings of the T2 analysis.  ...  MWF measurements depend upon the quality of the data acquisition, B1+ homogeneity and a range of fitting parameters.  ...  Results Extended Phase Graph -Flip Angle estimation. The reliability of the FA estimation by EPG depends predominantly on SNR.  ... 
doi:10.1101/2020.02.15.948976 fatcat:skncydsuzbfibgwasxsirxzdxa

VPG and EPG bend-numbers of Halin graphs

Mathew C. Francis, Abhiruk Lahiri
2016 Discrete Applied Mathematics  
and an EPG-representation using only one type of 2-bend paths.  ...  Similarly, the EPG bend-number b_e(G) of a graph G is the minimum k such that G has a B_k-EPG representation.  ...  A graph G is said to be an EPG graph if its vertices can be mapped to paths in a grid graph (a graph with vertex set {(x, y) : x, y ∈ N} and edge set {(x, y)(x ′ , y ′ ) : |(x − x ′ ) + (y − y ′ )| = 1  ... 
doi:10.1016/j.dam.2016.07.007 fatcat:22q263sagzfjbjjdo6isy2wgqi

Using 3D spatial correlations to improve the noise robustness of multi component analysis of 3D multi echo quantitative T2 relaxometry data

Dushyant Kumar, Hari Hariharan, Tobias D. Faizy, Patrick Borchert, Susanne Siemonsen, Jens Fiehler, Ravinder Reddy, Jan Sedlacik
2018 NeuroImage  
This method utilizes 3D spatial correlations present in anatomical/pathological tissues and underlying B1+-inhomogeneity or flip angle inhomogeneity to enhance the noise robustness of the reconstruction  ...  However, using B1 + -map would be a suboptimal strategy due to the limitation of extended phase graph (EPG) model that we implemented.  ...  The superscript "EPG" stands for the extended phase graph model and the subscript "MV" stands for "multi voxel".  ... 
doi:10.1016/j.neuroimage.2018.05.026 pmid:29763672 pmcid:PMC6492294 fatcat:wf6sru3ujzdnnnoenrkmcqqvne

Approximating MIS over equilateral B_1-VPG graphs [article]

Abhiruk Lahiri and Joydeep Mukherjee and C.R. Subramanian
2019 arXiv   pre-print
We present an approximation algorithm for the maximum independent set (MIS) problem over the class of equilateral B_1-VPG graphs.  ...  MIS algorithm over arbitrary B_1-VPG graphs.  ...  Acknowledgements : We thank an anonymous referee (of a related submission) for pointing out that a special type of input studied here actually induces a permutation graph, thereby leading to improved running  ... 
arXiv:1912.07957v1 fatcat:brympt2agjcdlo6ilglqm32ska

Articulatory and Acoustic Characteristics of German Fricative Clusters

Marianne Pouplier, Philip Hoole
2016 Phonetica: International Journal of Phonetic Science  
Conclusion: Our data suggest that similar principles of articulatory coordination underlie German fricative clusters independently of their segmental composition.  ...  We pursue the possibility that /f/#sibilant and /s#ʃ/ sequences are in principle subject to articulatory overlap in a similar fashion, yet due to independent articulators being involved, there is a significant  ...  For statistical testing, we obtained a Δ index value by subtracting the normalized acoustic index from the normalized EPG index on a token-by-token basis, setting acoustic and EPG signals in a direct relationship  ... 
doi:10.1159/000442590 pmid:26855044 fatcat:3u6vfz23vbglhk6ojmzjuewd44

Common resistance mechanisms are deployed by plants against sap-feeding herbivorous insects: insights from a meta-analysis and systematic review [article]

Daniel J Leybourne, Gudbjorg I Aradottir
2021 bioRxiv   pre-print
We show that insects feeding on resistant plants take longer to establish a feeding site and have their feeding duration suppressed two-fold compared with insects feeding on susceptible plants.  ...  Sap-feeding insects cause significant yield losses to the worlds crops, these insects feed using syringe-like mouthparts and electrophysiology can be used to compare feeding behaviour on susceptible and  ...  This produced two datasets per insect group ("Time to First Event" and "Duration of Event") which were sub-set across the main EPG phases (np, C, pd, F, G, E1, E2, sE2).  ... 
doi:10.1101/2021.11.05.467399 fatcat:7pmvavkrwvbhbbwgvvuoxx4svu

Constitutive expression of a grapevine polygalacturonase-inhibiting protein affects gene expression and cell wall properties in uninfected tobacco

Erik Alexandersson, John VW Becker, Dan Jacobson, Eric Nguema-Ona, Cobus Steyn, Katherine J Denby, Melané A Vivier
2011 BMC Research Notes  
the inhibition of ePGs.  ...  Polygalacturonase-inhibiting proteins (PGIPs) directly limit the effective ingress of fungal pathogens by inhibiting cell wall-degrading endopolygalacturonases (ePGs).  ...  The electron multiplier voltage was set at 500 V.  ... 
doi:10.1186/1756-0500-4-493 pmid:22078230 pmcid:PMC3339426 fatcat:bpnzobislnbfxgj6srflu6aheu

Patterns of soil-transmitted helminth infection and impact of four-monthly albendazole treatments in preschool children from semi-urban communities in Nigeria: a double-blind placebo-controlled randomised trial

Patrick Kirwan, Samuel O Asaolu, Síle F Molloy, Titilayo C Abiona, Andrew L Jackson, Celia V Holland
2009 BMC Infectious Diseases  
Our objectives were to describe the prevalence and intensity of STH infection and to investigate the effectiveness of repeated four-monthly albendazole treatments on STH infection in children aged one  ...  to 45% and 45% of the children being infected with Ascaris and mean epg being 1095 (S.E. 237) and 1126 (S.E. 182) in the treatment and placebo group respectively at baseline.  ...  The data on epg were assessed for normality visually and statistically.  ... 
doi:10.1186/1471-2334-9-20 pmid:19228385 pmcid:PMC2649135 fatcat:xjqw7huhs5ehhggovpqzdjyn34

In vivo investigation of the multi-exponential T2 decay in human white matter at 7 T: Implications for myelin water imaging at UHF

Vanessa Wiggermann, Alexander L MacKay, Alexander Rauscher, Gunther Helms
2020 NMR in Biomedicine  
Stimulated echoes arising from B1 + inhomogeneities were accounted for by the extended phase graph (EPG) algorithm.  ...  Fit-to-noise and signal-to-noise ratios were improved at 7 T but depended on B1 + homogeneity.  ...  With the introduction of the extended phase graph (EPG) (16, 17) , the effect of B + 1 -inhomogeneity on the T2 decay can now be accurately modeled.  ... 
doi:10.1002/nbm.4429 pmid:33118238 fatcat:7fk64lnitbgmjjvnowbrzen25i

Preface: LAGOS'13: Seventh Latin-American Algorithms, Graphs, and Optimization Symposium, Playa del Carmen, México — 2013

José Correa, Guillermo Durán, Luerbio Faria, Miguel Pizaña, Gelasio Salazar
2016 Discrete Applied Mathematics  
Slash and burn on graphs -Firefighting with general weights, by Vitor Costa, Simone Dantas, Mitre C.  ...  This issue contains full-length versions of selected papers from those presented at the Seventh Latin-American Algorithms, Graphs, and Optimization Symposium LAGOS'13, held on April 22th-26th, 2013, in  ...  Hoàng, studies the class of B1-EPG graphs (and subclasses of it), which are edge intersection graphs of the shapes in { } (and subsets of it).  ... 
doi:10.1016/j.dam.2016.05.007 fatcat:tbv2l3vfjnhenltu7ipqrn23hu
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