scholarly journals Diversidade de cepas de Stenotrophomonas maltophilia isoladas entre 1958 e 2021 e genotipadas por multilocus sequence typing

2021 ◽  
pp. 129-141
Author(s):  
Rebeca Vitória Da Silva Lage ◽  
Paula Vasconcelos Costa ◽  
Luciana Veloso Da Costa ◽  
Maria Helena Simões Villas Bôas ◽  
Marcelo Luiz Lima Brandão
Keyword(s):  
In Silico ◽  
Multilocus Sequence Typing ◽  
Spanning Tree ◽  
Stenotrophomonas Maltophilia ◽  
Minimum Spanning Tree ◽  
Neighbor Joining

O objetivo deste estudo foi avaliar os dados in silico de cepas de S. maltophilia (n=974) caracterizadas por Multilocus Sequence Typing (MLST) disponíveis no banco PubMLST isoladas entre 1958 e 2020. As cepas com perfil alélico completo (n=972) foram analisadas utilizando a árvore filogenética neighbor-joining, a ferramenta minimum spanning tree e o algoritmo eBURST. O índice de Simpson foi aplicado para calcular o poder de resolução do MLST para tipificação. A maioria das cepas depositadas são de origem clínica (87,6%) e oriundas da Ásia (47,1%). As cepas de S. maltophilia apresentaram alta diversidade genética quando avaliadas, sendo identificadas em 679 ST distintos, uma taxa de ~1,4 cepa/ST. O índice de Simpson calculado foi de 0,99. O Brasil possui 10 cepas depositadas classificadas em sete ST distintos, sendo quatro isolados de infecções em humanos. Em conclusão, o MLST apresentou-se como uma ferramenta poderosa para investigações epidemiológicas de cepas de S. maltophilia.

scholarly journals Converting MST to TSP Path by Branch Elimination

2020 ◽  
Vol 11 (1) ◽  
pp. 177
Author(s):  
Pasi Fränti ◽  
Teemu Nenonen ◽  
Mingchuan Yuan
Keyword(s):  
Spanning Tree ◽  
Closed Loop ◽  
Minimum Spanning Tree ◽  
Travelling Salesman Problem ◽  
Open Loop ◽  
Travelling Salesman ◽  
Elimination Algorithm ◽  
Number Of Iterations ◽  
Number Of Branches

Travelling salesman problem (TSP) has been widely studied for the classical closed loop variant but less attention has been paid to the open loop variant. Open loop solution has property of being also a spanning tree, although not necessarily the minimum spanning tree (MST). In this paper, we present a simple branch elimination algorithm that removes the branches from MST by cutting one link and then reconnecting the resulting subtrees via selected leaf nodes. The number of iterations equals to the number of branches (b) in the MST. Typically, b << n where n is the number of nodes. With O-Mopsi and Dots datasets, the algorithm reaches gap of 1.69% and 0.61 %, respectively. The algorithm is suitable especially for educational purposes by showing the connection between MST and TSP, but it can also serve as a quick approximation for more complex metaheuristics whose efficiency relies on quality of the initial solution.

Latency, Capacity, and Distributed Minimum Spanning Tree†

2020 ◽  
Author(s):  
John Augustine ◽  
Seth Gilbert ◽  
Fabian Kuhn ◽  
Peter Robinson ◽  
Suman Sourav
Keyword(s):  
Spanning Tree ◽  
Minimum Spanning Tree

DEVELOPING PROXIMITY GRAPHS BY PHYSARUM POLYCEPHALUM: DOES THE PLASMODIUM FOLLOW THE TOUSSAINT HIERARCHY?

2009 ◽  
Vol 19 (01) ◽  
pp. 105-127 ◽  
Author(s):  
ANDREW ADAMATZKY
Keyword(s):  
Foraging Behavior ◽  
Delaunay Triangulation ◽  
Spanning Tree ◽  
Physarum Polycephalum ◽  
Minimum Spanning Tree ◽  
Nearest Neighbour ◽  
Minimal Spanning Tree ◽  
Proximity Graphs ◽  
Relative Neighborhood Graph ◽  
Plasmodium Of Physarum Polycephalum

Plasmodium of Physarum polycephalum spans sources of nutrients and constructs varieties of protoplasmic networks during its foraging behavior. When the plasmodium is placed on a substrate populated with sources of nutrients, it spans the sources with protoplasmic network. The plasmodium optimizes the network to deliver efficiently the nutrients to all parts of its body. How exactly does the protoplasmic network unfold during the plasmodium's foraging behavior? What types of proximity graphs are approximated by the network? Does the plasmodium construct a minimal spanning tree first and then add additional protoplasmic veins to increase reliability and through-capacity of the network? We analyze a possibility that the plasmodium constructs a series of proximity graphs: nearest-neighbour graph (NNG), minimum spanning tree (MST), relative neighborhood graph (RNG), Gabriel graph (GG) and Delaunay triangulation (DT). The graphs can be arranged in the inclusion hierarchy (Toussaint hierarchy): NNG ⊆ MST ⊆ RNG ⊆ GG ⊆ DT . We aim to verify if graphs, where nodes are sources of nutrients and edges are protoplasmic tubes, appear in the development of the plasmodium in the order NNG → MST → RNG → GG → DT , corresponding to inclusion of the proximity graphs.

Fuzzy quadratic minimum spanning tree problem

2005 ◽  
Vol 164 (3) ◽  
pp. 773-788 ◽  
Author(s):  
Jinwu Gao ◽  
Mei Lu
Keyword(s):  
Spanning Tree ◽  
Minimum Spanning Tree ◽  
Minimum Spanning Tree Problem
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