Results 311 to 320 of about 2,110,315 (345)
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2023
This book is a warning and a toolkit for the future of forest recovery. The book investigates the critical biological threats endangering tree species native to the forests of eastern North America, providing a needed focus on this plight. The book suggests that if we are to save our forests, the first step is to recognize the threats in front of us ...
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This book is a warning and a toolkit for the future of forest recovery. The book investigates the critical biological threats endangering tree species native to the forests of eastern North America, providing a needed focus on this plight. The book suggests that if we are to save our forests, the first step is to recognize the threats in front of us ...
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Journal of Dance & Somatic Practices, 2022
This text reflects on an artistic practice based on repeated visits to chosen trees, performing for camera with them in the context of the project ‘Meetings with Remarkable and Unremarkable Trees’. The individual daily practice of becoming a tree, based on a yoga exercise, together with a variety of trees, is complemented with a collective online ...
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This text reflects on an artistic practice based on repeated visits to chosen trees, performing for camera with them in the context of the project ‘Meetings with Remarkable and Unremarkable Trees’. The individual daily practice of becoming a tree, based on a yoga exercise, together with a variety of trees, is complemented with a collective online ...
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Molecular Ecology, 1998
The practice of tracking geographical divergence along a phylogenetic tree has added an evolutionary perspective to biogeographic analysis within single species. In spite of the popularity of phylogeography, there is an emerging problem. Recurrent mutation and recombination both create homoplasy, multiple evolutionary occurrences of the same character ...
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The practice of tracking geographical divergence along a phylogenetic tree has added an evolutionary perspective to biogeographic analysis within single species. In spite of the popularity of phylogeography, there is an emerging problem. Recurrent mutation and recombination both create homoplasy, multiple evolutionary occurrences of the same character ...
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Mathematical Programming, 1994
The class of 2-tree graphs is defined inductively as follows: start with a single edge and add nodes by joining them to the two endpoints of an existing edge. Many NP-complete problems on graphs are polynomial when restricted to this class of graphs. In particular, the Steiner Tree problem is linear time solvable on graphs in this class.
F. Margot, Th. M. Liebling, A. Prodon
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The class of 2-tree graphs is defined inductively as follows: start with a single edge and add nodes by joining them to the two endpoints of an existing edge. Many NP-complete problems on graphs are polynomial when restricted to this class of graphs. In particular, the Steiner Tree problem is linear time solvable on graphs in this class.
F. Margot, Th. M. Liebling, A. Prodon
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Genome trees and the tree of life
Trends in Genetics, 2002Genome comparisons indicate that horizontal gene transfer and differential gene loss are major evolutionary phenomena that, at least in prokaryotes, involve a large fraction, if not the majority, of genes. The extent of these events casts doubt on the feasibility of constructing a 'Tree of Life', because the trees for different genes often tell ...
Igor B. Rogozin +3 more
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Mathematics Magazine, 2006
ture game Trinity, you have a gnomon you must screw into a hole?but the threads in the hole are going the wrong way. Wandering about, you encounter an "abstract sculpture," inscribed with the words Felix Klein 1849-1925. Nearby are strange leafy tunnels.
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ture game Trinity, you have a gnomon you must screw into a hole?but the threads in the hole are going the wrong way. Wandering about, you encounter an "abstract sculpture," inscribed with the words Felix Klein 1849-1925. Nearby are strange leafy tunnels.
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2017
This chapter considers the problem of counting trees. Every connected graph G has a spanning tree, that is, a connected acyclic subgraph containing all the vertices of G. If G has no cycles, it is its own unique spanning tree. If G has cycles, we can locate any cycle and delete one of its edges. Repeat this process until no cycle remains.
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This chapter considers the problem of counting trees. Every connected graph G has a spanning tree, that is, a connected acyclic subgraph containing all the vertices of G. If G has no cycles, it is its own unique spanning tree. If G has cycles, we can locate any cycle and delete one of its edges. Repeat this process until no cycle remains.
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, 1965 This thesis consists of a number of original stories and poems. The works attempt, in experimental forms, to portray certain basic human dilemmas in order to communicate their social, political, psychological or philosophical aspects. "The Butternut Tree" deals with different sets of relationships, some severed forcefully though desired, others forced ...
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1963
(Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
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(Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
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The Tree-to-Tree Correction Problem
Journal of the ACM, 1979The tree-to-tree correctmn problem Is to determine, for two labeled ordered trees T and T', the distance from T to T' as measured by the mlmmum cost sequence of edit operaUons needed to transform T into T' The edit operations investigated allow changing one node of a tree into another node, deleting one node from a tree, or inserting a node into a tree
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