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A characterisation of universal minimal total dominating functions in trees

E.J. Cockayne, C.M. Mynhardt
1995 Discrete Mathematics  
A total dominating function (TDF) of a graph G = (V, E) is a function f: V~ [0, 1] such that for each v~ V, ~u~Ntv)f(u)>~ 1, where N(v) denotes the set of neighbours of v.  ...  An MTDF whose convex combinations with any other MTDF are minimal is called a universal MTDF. In this paper we characterise universal MTDFs for trees. * Corresponding author. 0012-365X/95/$09.50  ...  Acknowledgements Financial support from the University of South Africa, the South African Foundation of Research Development and the Canadian Natural Sciences and Engineering Research Council is gratefully  ... 
doi:10.1016/0012-365x(93)e0192-7 fatcat:b6yny6bxyrfslkok4o7zs6vu4m

Universal minimal total dominating functions of trees

Alan Stacey
1995 Discrete Mathematics  
We show that any tree that has a universal minimal total dominating function has one which only takes 0-1 values. K 3 demonstrates that this fails for graphs in general.  ...  The notion of a total dominating function was first examined in [6] .  ...  The algorithm relies on the corresponding result for universal minimal dominating functions to that presented in this paper for total dominating functions, namely that if a tree has a universal, it has  ... 
doi:10.1016/0012-365x(93)e0143-r fatcat:gmng6keu75g6xlzkcd3fmqw3w4

Page 2605 of Mathematical Reviews Vol. , Issue 96e [page]

1996 Mathematical Reviews  
(SA-SAFR; Pretoria) A characterisation of universal minimal total dominating functions in trees. (English summary) Discrete Math. 141 (1995), no. 1-3, 75-84.  ...  An MTDF whose convex combinations with any other MTDF are minimal is called a universal MTDF. In this paper we characterise universal MTDFs for trees.” Bert L.  ... 

Minimum Spanning Trees on Random Networks

R. Dobrin, P. M. Duxbury
2001 Physical Review Letters  
Due to this geometric universality, we are able to characterise the energy of MST using a scaling distribution (P(ϵ)) found using uniform disorder.  ...  We show that the geometry of minimum spanning trees (MST) on random graphs is universal.  ...  The total cost of the shortest path tree is the sum of the costs of all of the paths in the tree.  ... 
doi:10.1103/physrevlett.86.5076 pmid:11384425 fatcat:mw6syaktt5gqznxugfjolqhcvq

Forest die-off following global-change-type drought alters rhizosphere fungal communities

Anna J M Hopkins, Katinka X Ruthrof, Joseph B Fontaine, George Matusick, Shannon J Dundas, Giles EStJ Hardy
2018 Environmental Research Letters  
Following a forest die-off three years previously, we collected soils beneath dead and alive trees within forest exhibiting high, minimal and relatively unaffected levels of forest die-off.  ...  We investigated rhizosphere fungal communities in soils beneath trees affected by a globalchange-type drought in a Mediterranean climate-type ecosystem in southwestern Australia, quantifying how fungal  ...  Acknowledgments The authors thank the Western Australian Department of Biodiversity ORCID iDs Anna J M Hopkins https:/ /orcid.org/0000-0001-8090-5544 Katinka X Ruthrof https:/ /orcid.org/0000-0003-2038  ... 
doi:10.1088/1748-9326/aadc19 fatcat:xe543jhqmzf7bkmfn53sv6fmtq

Contribution to the Knowledge of Martinique's Flora (Lesser Antilles)

2017 International Journal of Science and Research (IJSR)  
As a result, much of Martinique's plant formations are in little advanced stages.  ...  Irrespective of the bioclimate, they are composed of individuals in morphogenetic development accompanied by some mature specimens belonging to a previous dynamic stage.  ...  I am also grateful to the former Regional Council of Martinique (the current Territorial Collectivity of Martinique) for their financial aid and to the University of the West Indies (UA).  ... 
doi:10.21275/art20164658 fatcat:ectswljiejfsrpr6vfcfdodea4

Geometry of the quantum universe

J. Ambjørn, A. Görlich, J. Jurkiewicz, R. Loll
2010 Physics Letters B  
We study the geometry of such universes which appear in the path integral as a function of the bare coupling constants of the theory.  ...  A universe much like the (Euclidean) de Sitter space-time appears as background geometry in the causal dynamical triangulation (CDT) regularization of quantum gravity.  ...  We will now quantify their fractality in a more direct way, with the tree structure defined in terms of socalled "minimal necks" [14, 15] .  ... 
doi:10.1016/j.physletb.2010.05.062 fatcat:hxryu6x26bfp5hfrxhvwg72nxq

Multiproxy analyses of Lake Allos reveal synchronicity and divergence in geosystem dynamics during the Lateglacial/Holocene in the Alps

Rosine Cartier, Elodie Brisset, Frédéric Guiter, Florence Sylvestre, Kazuyo Tachikawa, Edward J. Anthony, Christine Paillès, Hélène Bruneton, Edouard Bard, Cécile Miramont
2018 Quaternary Science Reviews  
Dambrine (INRA-Savoie University) for help in soil determination and discussions. We are grateful to F. Ruaudel (IMBE) for CNS analyses and to A.  ...  Tonetto for the SEM expertise (Aix-Marseille University).  ...  Tree pollen is the sum of the Tree taxa to Total pollen. Pollen Assemblage Zones (PAZ) are based on cluster analysis. Fig. 7 . 7 Ostracod diagram as a function of depth (cm) and ages (cal. BP).  ... 
doi:10.1016/j.quascirev.2018.02.016 fatcat:hei3pvdig5c2hba2rjgzzpefsy

The legacy of forest disturbance on stream ecosystem functioning

André Frainer, Brendan G. McKie
2021 Journal of Applied Ecology  
In a space-for-time substitution experiment, we assessed changes in organic matter processing and in the functional and taxonomic composition of litter-consuming detritivores along a riparian forest age  ...  We found that the decomposition of leaf litter, a component of carbon cycling in forests, was higher in streams flowing through intermediately aged forest, and that several key attributes of the organisms  ...  Low decomposition rates are indicative of microbial-dominated decomposition, with a minimal contribution from benthic invertebrate consumers (Boyero et al., 2011) , and hence a low energy turn-over rate  ... 
doi:10.1111/1365-2664.13901 fatcat:k6zpfnobi5bnpp5nz6jxixnq2u

Biosynthesis of very long-chain fatty acids (C>24) in Atlantic salmon: Cloning, functional characterisation, and tissue distribution of an Elovl4 elongase

Greta Carmona-Antoñanzas, Óscar Monroig, James R. Dick, Andrew Davie, Douglas R. Tocher
2011 Comparative Biochemistry and Physiology - Part B: Biochemistry & Molecular Biology  
One member of the Elovl family, Elovl4, has been regarded as a critical enzyme in vertebrates in the production of the so-called very long-chain fatty acids (VLC-FA), a group of compounds that have been  ...  Our results are discussed in comparison with the functional analyses observed in Elovl4 proteins from other vertebrates, and also other Elovl proteins investigated previously in Atlantic salmon.  ...  A 5-bp deletion in ELOVL4 is associated with two related forms of autosomal dominant macular dystrophy. Nat. Genet. 27, 89-93.  ... 
doi:10.1016/j.cbpb.2011.02.007 pmid:21377536 fatcat:mryl37eyzjeuti3i5vjfrakgfu

Anti-Complex Sets and Reducibilities with Tiny Use

Johanna N. Y. Franklin, Noam Greenberg, Frank Stephan, Guohua Wu
2013 Journal of Symbolic Logic (JSL)  
In contrast with the notion of complexity, a set A is called anti-complex if the Kolmogorov complexity of the initial segments of A chosen by a recursive function is always bounded by the identity function  ...  In this context, we show the equivalence of anti-complexity and other lowness notions such as r.e. traceability or being weak truth-table reducible to a Schnorr trivial set.  ...  Since the use function for a total Turing functional is recursive (equivalently, the size of the n th truth-table of a tt-reduction is recursive), there is no uniform notion in this context.  ... 
doi:10.2178/jsl.7804170 fatcat:3wj435tyq5bsdlpsyxdg4lhyti

Minimum representative root distribution sampling for calculating slope stability in Pinus radiata D.Don plantations in New Zealand

Filippo Giadrossich, Massimiliano Schwarz, Michael Marden, Roberto Marrosu, Chris Phillips
2020 New Zealand Journal of Forestry Science  
Methods: This paper characterises the mechanical properties of Pinus radiata D.Don roots (the common tree species used for afforestation in New Zealand) by means of field pullout tests and by measuring  ...  Results: We show that to reach an effective level of root reinforcement, trees of 0.5 m DBH require a density of about 300 trees per hectare.  ...  Acknowledgements We thank the interns from Bern University of Applied Sciences (Switzerland) and University of Sassari (Italy), who over several years have contributed small pieces to the story and provided  ... 
doi:10.33494/nzjfs502020x68x fatcat:dpd4oywgdnbzlcipbp2jouoblq

Growth and volume based on permanent sample plots in forests managed by communities

L. Puri, H. Meilby, S. Rayamajhi, Y. P. Timilsina, N. P. Gautam, R. Subedi, H. O. Larsen
2013 Banko Janakari  
Moreover this work was possible only through the hard and backbreaking work of IOF faculty and students. The Danish Ministry of Foreign Affairs provided funding -104. DAN.8.L.716.  ...  Acknowledgements We owe thanks to the Forest User Groups that agreed to participate in this study and to the local community members who assisted the field data collection.  ...  To include estimates of firewood, volume of trees with a diameter lower than 10 cm was included. Total volume was estimated using volume functions developed by Sharma and Pukkala (1990) .  ... 
doi:10.3126/banko.v22i2.9194 fatcat:55dr2b7nbffelgqr74phcq5zea

Volume and Aboveground Biomass Models for Dry Miombo Woodland in Tanzania

Ezekiel Edward Mwakalukwa, Henrik Meilby, Thorsten Treue
2014 International Journal of Forestry Research  
Based on a sample of 142 trees and 57 shrubs from a 6,065 ha area of dry miombo woodland in Iringa rural district in Tanzania, regression models were developed for volume and biomass of three important  ...  Applied independent variables were log-transformed diameter, height, and wood basic density, and in each case a range of different models were tested.  ...  The authors gratefully acknowledge the help and contributions of Goodluck Moshi, their driver, Venancia Mlelwa, John Shesighe and Tulamwona Ernest at Sokoine University of Agriculture who did most of the  ... 
doi:10.1155/2014/531256 fatcat:ui5722fkljeathtqu7ylkqc5em

Spontaneous succession of riparian fynbos: Is unassisted recovery a viable restoration strategy?

M.K. Reinecke, A.L. Pigot, J.M. King
2008 South African Journal of Botany  
The invasion of alien trees is a major threat to the freshwater resources and biodiversity of South Africa.  ...  We propose that the absence of riparian trees may have been responsible for precipitating the transition to a community dominated by weedy nitrophilous grasses, and find evidence that this may be perpetuated  ...  The Zoology Department at the University of Cape Town for housing the work conducted for the analysis of these data.  ... 
doi:10.1016/j.sajb.2008.01.171 fatcat:in54o42xofhkfbwpwmtckylynq
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