Results 51 to 60 of about 1,360 (113)

On General Sum‐Connectivity Index and Number of Segments of Fixed‐Order Chemical Trees

Journal of Mathematics, Volume 2025, Issue 1, 2025.
Nowadays, one of the most active areas in mathematical chemistry is the study of the mathematical characteristics associated with molecular descriptors. The primary objective of the current study is to find the largest value of χα of graphs in the class of all fixed‐order chemical trees with a particular number of segments for α > 1, where χα is the ...
Muzamil Hanif, Akhlaq A. Bhatti, Hicham Saber, Adel A. Attiya, Akbar Ali, Guo Zhong   +5 more
wiley   +1 more source

On the Multiplicative Sum Zagreb Index of Molecular Trees With Given Order and Number of Branching Vertices

Journal of Mathematics, Volume 2025, Issue 1, 2025.
The multiplicative sum Zagreb index of a graph G is defined as the product of the sum of the degrees of adjacent vertices of G. A molecular tree is an acyclic connected graph with maximum degree at most 4. A vertex in a molecular tree with degree 3 or 4 is referred to as a branching vertex. In this paper, we consider the class of all molecular trees of
Sadia Noureen, Mubashar Abbas, Abdulaziz Mutlaq Alotaibi, Jaya Percival Mazorodze, Taher S. Hassan, Akbar Ali, Zafar Ullah   +6 more
wiley   +1 more source

The Minimum Size of a Graph with Given Tree Connectivity

Discussiones Mathematicae Graph Theory, 2021
For a graph G = (V, E) and a set S ⊆ V of at least two vertices, an S-tree is a such subgraph T of G that is a tree with S ⊆ V (T). Two S-trees T1 and T2 are said to be internally disjoint if E(T1) ∩ E(T2) = ∅ and V (T1) ∩ V (T2) = S, and edge-disjoint ...
Sun Yuefang, Sheng Bin, Jin Zemin
doaj   +1 more source

Extremal Values on the General Degree–Eccentricity Index of Unicyclic Graphs of Fixed Diameter

Journal of Mathematics, Volume 2025, Issue 1, 2025.
For a connected graph G and two real numbers a, b, the general degree–eccentricity index of G is given by DEIa,bG=∑v∈VGdGavecGbv, where V(G) represent the vertex set of graph G, dG(v) denotes the degree of vertex v, and ecG(v) is the eccentricity of v in G, that is, the maximum distance from v to another vertex of G. This index generalizes several well‐
Mesfin Masre, G. Muhiuddin
wiley   +1 more source

The classification of edges and the change in multiplicity of an eigenvalue of a real symmetric matrix resulting from the change in an edge value

Special Matrices, 2017
We take as given a real symmetric matrix A, whose graph is a tree T, and the eigenvalues of A, with their multiplicities. Each edge of T may then be classified in one of four categories, based upon the change in multiplicity of a particular eigenvalue ...
Toyonaga Kenji, Johnson Charles R.
doaj   +1 more source

Finite Ball Intersection Property of the Urysohn Universal Space [PDF]

, 2014
In a paper published posthumously, P.S. Urysohn constructed a complete, separable metric space that contains an isometric copy of every complete separable metric space, nowadays referred to as the Urysohn universal space.
Aksoy, Asuman Guven, Ibragimov, Zair
core  

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

Veterinary 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, Geoffrey A. Wood, Charlotte Pye, Khalil Karimi, Anthony Yu, Myles St‐Denis, Katherine Blake, Sugandha Raj, Samson Oladokun, Shayan Sharif   +9 more
wiley   +1 more source

Further results on permanents of Laplacian matrices of trees

Open Mathematics
The research on the permanents of graph matrices is one of the contemporary research topic in algebraic combinatorics. Brualdi and Goldwasser characterized the upper and lower bounds of permanents of Laplacian matrices of trees.
Wu Tingzeng, Dong Xiangshuai
doaj   +1 more source

Some improved bounds on two energy-like invariants of some derived graphs

Open Mathematics, 2019
Given a simple graph G, its Laplacian-energy-like invariant LEL(G) and incidence energy IE(G) are the sum of square root of its all Laplacian eigenvalues and signless Laplacian eigenvalues, respectively. This paper obtains some improved bounds on LEL and
Cui Shu-Yu, Tian Gui-Xian
doaj   +1 more source

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

Infant 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, Mirjam Oosterman, Anne Tharner, Carlo Schuengel   +3 more
wiley   +1 more source