Results 111 to 120 of about 1,442 (223)

Isolation of Metabolites With Antiviral Activity From the Brown Algae Dictyota fasciola and Dictyota mediterranea

Chemistry &Biodiversity, Volume 23, Issue 6, June 2026.
Twenty‐one compounds, including six dolabellanes diterpenes and one germacrene sesquiterpene that are new natural products, are reported from the brown algae Dictyota fasciola and Dictyota mediterranea collected from the Aegean Sea. Among them, some exhibit considerable antiviral activity against RNA (HCoV‐NL63, ZIKV) and DNA (HSV‐1) viruses.
Aikaterini Koutsaviti, Elsi‐Evangelia Andriotaki, Maria Harizani, Katarzyna Owczarek, Magdalena Pachota, Aleksandra Synowiec, Artur Szczepański, Paweł Botwina, Krzysztof Pyrć, Vassilios Roussis, Efstathia Ioannou   +10 more
wiley   +1 more source

Signed bicyclic graphs minimizing the least Laplacian eigenvalue

, 2018
A signed graph is a pair (G,sigma), where G is a graph and sigma is the sign function on the edges of G. For a signed graph we consider the Laplacian matrix defined as L=D-A, where D is the matrix of vertices degrees of G and is the (signed) adjacency ...
Brunetti, Maurizio, Ciampella, Adriana, Belardo, Francesco   +2 more
core   +1 more source

On Distance Laplacian Energy of Unicyclic and Bicyclic Graphs

Axioms
For a connected graph G, let DL(G) be its distance Laplacian matrix and λ1(G)≥λ2(G)≥…≥λn−1(G)>λn(G)=0 be its DL eigenvalues. The DL energy of G is defined as DLEG=∑i=1nλi(G)−2WGn, where W(G) is the Wiener index of G.
Dan Li, Shiqi Zhou
doaj   +1 more source

Building Resilience: Empowering Agro‐Pastoralists Against Climate Variability in Laikipia, Kenya

Climate Resilience and Sustainability, Volume 5, Issue 1, June 2026.
ABSTRACT Climate change poses significant challenges for agricultural systems in Africa, particularly affecting agro‐pastoral communities dependent on crops and livestock for their livelihoods. This study investigates the impact of adaptation strategies on climate resilience among agro‐pastoral communities in Laikipia County, Kenya. It applies the Food
Cyrille Samson Awuonda, John Olwande, Gideon Aiko Obare   +2 more
wiley   +1 more source

Some results on the spectral radii of bicyclic graphs

, 2010
A bicyclic graph is a connected graph in which the number of edges equals the number of vertices plus one. Let Δ(G) and ρ(G) denote the maximum degree and the spectral radius of a graph G, respectively.
Yan Chen, Yuan, Xi-Ying, Chen, Yan, Xi-Ying Yuan   +3 more
core   +1 more source

On Sombor index and graph energy of some chemically important graphs

Examples and Counterexamples
Sombor index of a graph G=(V(G),E(G)) is provided by the expression ∑uv∈E(G)du2+dv2, where dx is the degree of the vertex x∈V(G). The energy of a graph is the quantity given by the total of the absolute values of its adjacency matrix’s eigenvalues.
Md Selim Reja, Sk. Md. Abu Nayeem
doaj   +1 more source

Synthesis of Levoglucosenone‐Based Amphiphilic Molecules via Microwave‐Assisted Michael Additions

Chemistry–Methods, Volume 6, Issue 6, June 2026.
Comparison between the conventional and the sustainable synthetic microwave‐based approach for Michael addition reactions on LGO developed in this work. Aligning with the objectives of the EU chemicals strategy for sustainability, an ultrarapid, safe and sustainable method for producing a library of levoglucosenone (LGO)‐based amphiphilic molecules was
Maria Jose Calandri, Barbara Benedetti, Léa Charrier, Dinis O. Abranches, James R. Sherwood, Gareth O. Lloyd, João A. P. Coutinho, Con Robert McElroy, Alessandro Pellis   +8 more
wiley   +1 more source

Solution to a conjecture on the maximal energy of bipartite bicyclic graphs

, 2011
The energy of a simple graph G, denoted by E(G), is defined as the sum of the absolute values of all eigenvalues of its adjacency matrix. Let Cn denote the cycle of order n and Pn6,6 the graph obtained from joining two cycles C6 by a path Pn-12 with its ...
Yongtang Shi, Li, Xueliang, Shengjin Ji, Xueliang Li, Huo, Bofeng, Shi, Yongtang, Ji, Shengjin, Bofeng Huo   +7 more
core   +1 more source

On the Extremal Weighted Mostar Index of Bicyclic Graphs

Axioms
Let G be a simple connected graph with edge set E(G) and vertex set V(G). The weighted Mostar index of a graph G is defined as w+Mo(G)=∑e=uv∈E(G)(dG(u)+dG(v))|nu(e)−nv(e)|, where nu(e) denotes the number of vertices closer to u than to v for an edge uv ...
Yuwei He, Mengmeng Liu
doaj   +1 more source

Real‐Time Road Obstacle Detection System to Enhance Road Safety on African Roads

Engineering Reports, Volume 8, Issue 6, June 2026.
This study presents a cost‐effective real‐time road obstacle detection system using a YOLOv3 model optimized for deployment on resource‐constrained devices. Trained on African road‐specific datasets, the system improves safety by detecting vehicles, wildlife, and pedestrians, achieving high accuracy with reduced inference time and memory usage ...
Pison Mutabarura, Nicasio Maguu Muchuka, Davies Rene Segera   +2 more
wiley   +1 more source