Results 31 to 40 of about 107 (89)

Galois connections between sets of paths and closure operators in simple graphs

open access: yesOpen Mathematics, 2018
For every positive integer n,we introduce and discuss an isotone Galois connection between the sets of paths of lengths n in a simple graph and the closure operators on the (vertex set of the) graph.
Šlapal Josef
doaj   +1 more source

A Note on the Crossing Numbers of 5-Regular Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2020
The crossing number cr(G) of a graph G is the smallest number of edge crossings in any drawing of G. In this paper, we prove that there exists a unique 5-regular graph G on 10 vertices with cr(G) = 2.
Ouyang Zhangdong
doaj   +1 more source

Wiener and Additive Degree‐Based Topological Indices of Linear Functional Graphs Over Finite‐Dimensional Vector Spaces

open access: yesJournal of Applied Mathematics, Volume 2025, Issue 1, 2025.
This article explores numerous significant additive topological indices based on degrees for linear functional graphs over finite‐dimensional vector spaces. Specifically, we derive some unique topological indices, such as the eccentricity‐based indices and the Wiener index.
Vinnarasi L.   +4 more
wiley   +1 more source

On the Intersection Graphs Associeted to Posets

open access: yesDiscussiones Mathematicae - General Algebra and Applications, 2020
Let (P, ≤) be a poset with the least element 0. The intersection graph of ideals of P, denoted by G(P), is a graph whose vertices are all nontrivial ideals of P and two distinct vertices I and J are adjacent if and only if I ∩ J ≠ {0}.
Afkhami M.   +2 more
doaj   +1 more source

Computation of Differential, Integral Operators and Quantitative Structure–Property Analysis of Boron α‐Icosahedral Nanosheet

open access: yesJournal of Mathematics, Volume 2025, Issue 1, 2025.
In its crystalline state, the α‐icosahedral nanosheet of boron demonstrates superconductivity and thermal electronic properties. Mathematical research on a graph’s structure yields a graph descriptor, a numerical measure. Chemical graph theory employs connectivity descriptors to analyze molecular structures, providing crucial insights into many ...
Khalil Hadi Hakami   +3 more
wiley   +1 more source

Rotor-Routing Induces the Only Consistent Sandpile Torsor Structure on Plane Graphs

open access: yesForum of Mathematics, Sigma, 2023
We make precise and prove a conjecture of Klivans about actions of the sandpile group on spanning trees. More specifically, the conjecture states that there exists a unique ‘suitably nice’ sandpile torsor structure on plane graphs which is induced by ...
Ankan Ganguly, Alex McDonough
doaj   +1 more source

Analysis of the immunomodulatory properties of mycobacterium cell wall fraction on the cytokine production of peripheral blood mononuclear cells of healthy dogs

open access: yesVeterinary Dermatology, Volume 35, Issue 6, Page 595-604, December 2024.
Background – Mycobacterium cell wall fraction (MCWF) is derived from nonpathogenic Mycobacterium phlei and is used as an immunomodulatory compound in clinical practice, yet its mode‐of‐action requires further research. Objective – To evaluate the host response to MCWF in canine peripheral blood mononuclear cells (PBMCs) by using enzyme‐linked ...
Robert Ward   +9 more
wiley   +1 more source

Testing reliability and validity of practitioner‐rated parental sensitivity: A novel tool for practice

open access: yesInfant Mental Health Journal: Infancy and Early Childhood, Volume 45, Issue 2, Page 234-246, March 2024.
Abstract Improving parental sensitivity is an important objective of interventions to support families. This study examined reliability and validity of parental sensitivity ratings using a novel package of an e‐learning tool and an interactive decision tree provided through a mobile application, called the OK! package.
Mirte L. Forrer   +3 more
wiley   +1 more source

Sharp Upper Bounds on the Clar Number of Fullerene Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2018
The Clar number of a fullerene graph with n vertices is bounded above by ⌊n/6⌋ − 2 and this bound has been improved to ⌊n/6⌋ − 3 when n is congruent to 2 modulo 6.
Gao Yang, Zhang Heping
doaj   +1 more source

On the Hamiltonian Number of a Plane Graph

open access: yesDiscussiones Mathematicae Graph Theory, 2019
The Hamiltonian number of a connected graph is the minimum of the lengths of the closed spanning walks in the graph. In 1968, Grinberg published a necessary condition for the existence of a Hamiltonian cycle in a plane graph, formulated in terms of the ...
Lewis Thomas M.
doaj   +1 more source

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