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Koegler, Xavier. "Population protocols, games and large populations". Paris 7, 2012. http://www.theses.fr/2012PA077132.
Pełny tekst źródłaPopulation protocols were introduced to capture the specifies of opportunistic networks of tny mobile agents with limited memory and capable of wireless communication in pairs. This thesis aims at extending the understanding and analysis of population protocols as well as their links to other models of population dynamics including ones from game theory. The first contribution of this thesis is to translate in terms of population protocols the dynamics of a population of agents playing a game repeatedly against each-other and adapting their strategy according to the PAVLOV behaviour. We show that protocols born from games are exactly as powerful as general population protocols. The second contribution consists in the study of the impact of symmetry on games and in the transitions of a population protocol to show that, if symmetric population protocols are equivalent to general protocols, symmetric games are significantly less powerful. The third contribution is to show how the dynamic of a population protocol can be approximated by an ordinary differential equation when the population grows to infinity. We then define a computation by a large population to be the convergence of this differential equation to a stable equilibrium. The fourth and final contribution of this thesis is the characterisation of the numbers computable in the above sense as exactly the algebraic real numbers in [0,1]
Lundy, Ian J. "Theoretical population genetics of spatially structured populations /". Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phl962.pdf.
Pełny tekst źródłaMartien, Karen Kay Fear. "Conservation of spatially structured populations : lessons from population genetics /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9979969.
Pełny tekst źródłaGagnon, Nicolas. "Mesure et analyse de l'effet fondateur dans les populations de Charlevoix et du Bas-Saint-Laurent". Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1998. http://theses.uqac.ca.
Pełny tekst źródłaBilodeau, Mélanie. "Caractéristiques démogénétiques des populations de l'Abitibi et du Témiscamingue /". Thèse, Chicoutimi : Université du Québec à Chicoutimi, 2002. http://theses.uqac.ca.
Pełny tekst źródłaSelf, Eric C. "Population analysis a methodology for understanding populations in COIN environments". Thesis, Monterey, California. Naval Postgraduate School, 2008. http://hdl.handle.net/10945/3810.
Pełny tekst źródłaBurke, Mark C. Self Eric C. "Population analysis a methodology for understanding populations in COIN environments /". Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Dec/08Dec%5FBurkeM.pdf.
Pełny tekst źródłaThesis Advisor(s): Gregg, Heather. "December 2008." Description based on title screen as viewed on January 30, 2009. Includes bibliographical references (p. 71-74). Also available in print.
Grillenberger, Bernd K. "Biogeography, population genetics and mating systems of natural Nasonia populations". [S.l. : Groningen : s.n. ; University Library Groningen] [Host], 2009. http://irs.ub.rug.nl/ppn/317.
Pełny tekst źródłaChampagnon, Jocelyn. "Conséquences des introductions d’individus dans les populations exploitées : l’exemple du Canard Colvert Anas platyrhynchos". Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20147/document.
Pełny tekst źródłaThe consequences of releasing captive-reared game animals into the wild have received little attention, despite their potential impact for receiving populations in terms of demography, behaviour, morphometrics, genetics and pathogens. The present study considers Mallards Anas platyrhynchos released for hunting purposes, an increasing practice in Europe over the last 30 years. Because of domestication process in game farm facilities, our study shows high natural mortality of these ducks once released compared to wild Mallards, in addition to high vulnerability to hunting. A clear genetic differentiation allows discrimination of released and wild Mallards. Hybridization with wild Mallards exists, but did not result into significant introgression. Generally, genetic as well as demographic contributions of captive-bred birds to the natural population were low, but a morphological modification associated with releases was recorded over 30 years in natural population. Ecological consequences of the releases for the wild population seem to be limited, but caution should be maintained on the possible transmission of pathogens (occasionally high prevalence of avian Influenza A in some breeding facilities) and the genetic risks associated with long-term releases
Pokalyuk, Cornelia [Verfasser], i Peter [Akademischer Betreuer] Pfaffelhuber. "Patterns of selection in subdivided populations = Selektionsmuster in strukturierten Populationen". Freiburg : Universität, 2012. http://d-nb.info/112346961X/34.
Pełny tekst źródłaTheodorou, Konstantinos. "Processus génétiques au sein de petites populations et de populations fragmentées : implications pour la biologie de la conservation". Paris 6, 2002. http://www.theses.fr/2002PA066550.
Pełny tekst źródłaLavoie, Ève-Marie. "Étude comparative des caractéristiques démogénétiques des populations du Bas-Saguenay, du Haut-Saguenay et du Lac-St-Jean /". Thèse, Chicoutimi : Ste-Foy : Université du Québec à Chicoutimi ; Université Laval, 2003. http://theses.uqac.ca.
Pełny tekst źródłaBibliogr.: f. [79]-83. Document électronique également accessible en format PDF. CaQCU
McRae, Allan F. "Quantitative and population genetic analyses of domesticated and wild sheep populations". Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/15362.
Pełny tekst źródłaCole-Showers, Curtis Lanre. "Population structure and demographics in Nigerian populations utilizing Y-chromosome markers". University of the Western Cape, 2014. http://hdl.handle.net/11394/5326.
Pełny tekst źródłaNigeria is peopled by ethnically and linguistically diverse populations of which little were known until the last few millennial. The absence of major natural geographical barrier increases the possibility of the populations being affected by the same demographic events. The aim of this thesis was to ascertain the genetic variations and demographics in five major Nigerian populations using Y-markers. This was done by determining the genetic structures of the Afro-asiatic speaking Hausa (n=78) of Northern Nigeria and the Niger Congo speaking populations of Igbo (n=119), Yoruba (n=238), Bini (n=13) and Ijaw (n=15) of Southern Nigeria all spread over 22 geographical origins and four (North, South east, south west and South south) geographical regions. They were compared with more than 2000 individuals from 46 populations of 20 other African and Middle Eastern countries, in published literature. The Scientific Working Group on DNA Analysis Methods (SWGDAM) recommended Y-Short Tandem Repeats (STRs) and nine Y-Single Nucleotide Polymorphisms (SNPs) haplogroups were typed with multiplex Polymerase Chain Reaction (PCR), Restriction Fragment Length Polymorphisms (RFLP) and High Resolution Melting (HRM). Summary statistics and measures of diversity were determined. Population structure was assessed with Population Pairwise Differences, hierarchical Analysis of Molecular Variance, Multidimensional scaling and correspondence analysis plots. Mantel’s test was used to assess the correlation of genetic distances with geographic distances. Demographic inferences were assessed with lineage based Network reconstruction, Spatial autocorrelation plots, effective migrants per population and both Inter and Intra-lineages Times to the Most Recent Common Ancestor (TMRCA). The patterns of diversity of the Y-markers showed a North-South gradient and a notable sub-structure among the Hausa populations. The Niger-Congo speakers displayed rare presence of haplogroups R and E1b1b but a preponderance of E1b1a7. Overall, the Y markers showed high diversities and significant genetic sub-structure within the Hausa populations of Nigeria with stronger linguistic than geographical bias. The demographic evaluations gave credence for genetic validation of both historical records and archeological findings among these Nigerian populations. These populations showed stronger affiliations with other sub-Saharan African populations rather than with North African or Middle Eastern populations, lacking evidence for the Middle Eastern origins of the male founders of these populations. Finally, the contribution of these Nigerian dataset would greatly enhance the Africa meta-population on the YHRD with more than 274 new haplotypes of forensic estimation significance.
Martins, Helena. "Méthodes statistiques pour identifier l'adaptation locale dans les populations continues et mélangées". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAS022/document.
Pełny tekst źródłaFinding genetic signatures of local adaptation is of great interest for many population genetic studies. Common approaches to sorting selective loci from their genomic background focus on the extreme values of the fixation index, FST, across loci. However, the computation of the fixation index becomes challenging when the population is genetically continuous, when predefining subpopulations is a difficult task, and in the presence of admixed individuals in the sample. In this thesis, we present a new method to identify loci under selection based on an extension of the FST statistic to samples with admixed individuals. Considering our goal of exploring statistical methods to identify local adaptation in admixed population, we included spatial data to compute ancestry coefficients and allele frequencies. To enrich our work, we investigated the effects of linkage disequilibrium and LD-pruning methods in genome scans for selection
Herbots, Hilde Maria Jozefa Dominiek. "Stochastic models in population genetics : genealogy and genetic differentiation in structured populations". Thesis, Queen Mary, University of London, 1994. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1482.
Pełny tekst źródłaLaine, Kari. "Long-term variations in plant quality and quantity in relation to cyclic microtine rodents at Kilpisjärvi, Finnish Lapland". Oulu, Finland : University of Oulu, 1988. http://catalog.hathitrust.org/api/volumes/oclc/18696609.html.
Pełny tekst źródłaBrännström, Åke. "Modelling animal populations". Doctoral thesis, Umeå universitet, Matematik och matematisk statistik, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-205.
Pełny tekst źródłaFryer, Christopher Lee 1969. "Neutron star populations". Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/298809.
Pełny tekst źródłaBergeron, Josée. "Contribution différentielle des ancêtres d'origine acadienne au bassin génétique des populations régionales du Québec /". Thèse, Chicoutimi : Ste-Foy : Université du Québec à Chicoutimi. Université Laval, 2005. http://theses.uqac.ca.
Pełny tekst źródłaBibliogr.: f. [94]-103. Document électronique également accessible en format PDF. CaQCU
Banks, John E. "The effects of landscape heterogeneity on insect populations : a study of pattern and scale /". Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5166.
Pełny tekst źródłaCorcoran, Pádraic. "Neurospora tetrasperma from Natural Populations : Toward the Population Genomics of a Model Fungus". Doctoral thesis, Uppsala universitet, Evolutionsbiologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-208791.
Pełny tekst źródłaOlsson, Fredrik. "Inbreeding, Effective Population Sizes and Genetic Differentiation : A Mathematical Analysis of Structured Populations". Doctoral thesis, Stockholms universitet, Matematiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-115708.
Pełny tekst źródłaAt the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.
黃道全 i Richard Huang. "Spatial variation in Cellana grata populations: the interplay of population dynamics and foodavailability". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31243125.
Pełny tekst źródłaHindle, Bethan J. "Unravelling the effects of environmental variation on the population dynamics of structured populations". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/19466/.
Pełny tekst źródłaRobin, Annie. "Synthese de population : un modele de la galaxie et de ses populations stellaires". Besançon, 1989. http://www.theses.fr/1989BESA2049.
Pełny tekst źródłaNicol, Elizabeth. "Long-term effects of oestrogenic effluent exposure on wild fish populations". Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/10826.
Pełny tekst źródłaPaltiel, Charles J. "An analysis of the 1994-1996 northern Strait of Georgia oyster survey". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51440.pdf.
Pełny tekst źródłaRobert, Alexandre. "Interactions démographiques et génétiques dans les petites populations : applications aux populations restaurées". Paris 6, 2003. http://www.theses.fr/2003PA066286.
Pełny tekst źródłaWaldick, Ruth. "Assessing the status of the endangered North Atlantic right whale using genetic and demographic data". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ66244.pdf.
Pełny tekst źródłaHancock, Andrew. "The biology and fishery of Roe's abalone Haliotis roei Gray in south-western Australia, with emphasis on the Perth fishery /". Connect to this title, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0068.
Pełny tekst źródłaRohrer, Wendy L. "A biosystematic study of the rare plant Paronychia virginica Sprengel (Caryophyllaceae) employing morphometric and allozyme analyses". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/46520.
Pełny tekst źródłaMaster of Science
Larson, Shawn Elizabeth. "Genetic and endocrine related variability of sea otters, Enhydra lutris /". Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5360.
Pełny tekst źródłaSamia, Yasmine. "Persistence of River Populations". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34495.
Pełny tekst źródłaIrwin, Andrew J. "Evolution in structured populations". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ54060.pdf.
Pełny tekst źródłaStephen, Linda J. "Antiepileptic drugs - treating populations". Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/2005/.
Pełny tekst źródłaAlford, Max. "Impulsivity in forensic populations". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33164.
Pełny tekst źródłaMendes, Coutinho Renato. "Dynamics of structured populations". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/143435.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Esta tese aborda a dinâmica de populações biológicas estruturadas. Essas estruturas podem ser quaisquer características que distinguam indivíduos da mesma população: sexo, idade, estágio, tamanho, localização espacial. Exploramos uma variedade de sistemas ecológicos e estratégias de modelagem, trabalhando com biólogos e ecólogos em problemas específicos. Estudamos alguns modelos espaciais explícitos para dispersão em conexão com estrutura de estágio. Isto inclui um modelo de equaçõesintegrais a diferenças para a invasão de moscas varejeiras no Brasil durante os anos 70, parametrizado com dados tanto de laboratório quanto de campo para prever \emph{a posteriori} a velocidade de invasão, obtendo boa concordância. Também estudamos o fenômeno conhecido como desconexão de \emph{habitat}, em que indivíduos imaturos de espécies com história de vida complexa, tais como anfíbios dependentes de cursos d'água para reproduzir, são fisicamente separados do seu \emph{habitat} adulto, o que aumenta sua mortalidade drasticamente e pode levar a um limiar de extinção. Investigamos ainda um modelo para migração a partir de uma mancha em uma paisagem com forte sazonalidade, onde a dispersão é possível somente durante uma parte do ano, levando a regimes distintos dependendo da duração dessa estação em relação ao tempo característico de difusão na matriz. Atacamos também problemas envolvendo a coexistência de espécies em comunidades, começando com a dinâmica de coexistência de duas espécies relacionadas por mutualismo intraguilda -- predadores de um recurso comum compartilhado, mas que se beneficiam da presença uma da outra devido ao aumento da eficiência de predação, levando a coexistência estável. Além disso, desenvolvemos um modelo eco-epidemiológico para a transmissão de malária na mata Atlântica, que incorpora fatores ecológicos na taxa de picadas e tamanho da população de mosquitos.Este modelo é parametrizado com dados e explica a ausência da transmissão de malária nesta região, em contraste ao modelo de Ross-MacDonald. Introduzimos um novo quadro teórico para prever a dinâmica populacional de animais de sangue frio levando em conta a variação de temperatura e a estrutura de estágios. Em particular, incorporamos características de história de vida (taxas de nascimento, morte e desenvolvimento) e sua resposta à temperatura a um modelo de dinâmica de populações, aplicando-o a duas questões: viabilidade da população e competição intra\hyp específica dependente de temperatura. Finalmente, exploramos a dinâmica de comunidades predador-presa nas quais cada população é composta por muitas espécies. Presas podem investir mais em defesa contra predadores às custas de uma menor taxa de crescimento, ao passo que predadores podem ser mais ou menos seletivos, porém os mais seletivos são mais eficientes. Essas características variam ao longo de um eixo contínuo, com cada valor correspondendo a uma espécie. Embora a teoria tradicional simplifique o sistema modelando apenas médias e variâncias, nós seguimos a dinâmica do sistema completo para descobrir como distribuições de características com grande variância, especialmente as bimodais, alteram os resultados da dinâmica de comunidades.Observamos vários tipos de dinâmica, e determinamos sob quais circunstâncias espera-se ver diferenças drásticas entre os modelos usuais e o nosso.
This thesis broaches the dynamics of structured biological populations. These structures consist of anything that distinguishes individuals of the same population: sex, age, stage, size, spatial location, individual characteristics, etc. We explored a wide range of ecological systems and modeling approaches, working closely with biologists and ecologists in problems arising in specific contexts. We studied some spatially explicit models for dispersal in connection with stage structure. Those include an integrodifference model for a blowfly invasion in Brazil during the 1970s, parametrized with laboratory and reanalyzed field data to predict a posteriori the invasion speed, obtaining a reasonable agreement. We also study the phenomenon known as habitat split, where immature individuals of species with complex life history, such as amphibians dependent on water streams to reproduce, are physically separated from their adult habitat, what can increase their mortality dramatically and lead to sharp extinction thresholds. We also investigate a model for population migration from a patch in a scenario of strong seasonality, where dispersal is possible only during part of the year, leading to distinct scenarios depending on that duration relative to the characteristic time for diffusion into the matrix. Then we look at problems involving coexisting species in communities, beginning with the dynamics and coexistence of two species engaging in intraguild mutualism, in which they are both specialist predators on a common, shared resource, but benefit from each other’s presence because of increased predation efficiency, leading to stable coexistence. We also develop an eco-epidemiological model for malaria transmission in the Atlantic Forest that incorporates feedbacks from ecological factors into biting rate and mosquito population size. Parametrized with data, it explains the absence of malaria transmission in the area, in contrast to the Ross-MacDonald model. We introduce a novel framework to predict the population dynamics of cold-blooded animals taking into account temperature variation and stage structure. We use individual life-history traits (birth, death and development rates) and their response to temperature to parametrize the population dynamics model, applying it to two sets of questions: population viability and (temperature-dependant) intra-specific competition. Finally, we explore the dynamics of predator-prey communities in which each population is composed by many species, characterized by their traits. Prey can invest more in defense against predators, at the cost of slower growth, while predators can be more or less selective on which prey it feeds on, but selective predators are more efficient. These traits can vary along a range of values, each species corresponding to a trait value. While traditional theory simplifies the description of the system by modeling only the aggregate measures of the distribution of traits in the population, we follow the dynamics of the whole system in order to learn how trait distributions with large variance, especially bimodal ones, change the outcomes of the community dynamics. We observe a range of behaviors, and characterize under which circumstances we expect to see drastic deviations from the usual aggregate models.
FAPESP: 2010/09464-1
Coutinho, Renato Mendes. "Dynamics of structured populations /". São Paulo, 2015. http://hdl.handle.net/11449/143435.
Pełny tekst źródłaResumo: Esta tese aborda a dinâmica de populações biológicas estruturadas. Essas estruturas podem ser quaisquer características que distinguam indivíduos da mesma população: sexo, idade, estágio, tamanho, localização espacial. Exploramos uma variedade de sistemas ecológicos e estratégias de modelagem, trabalhando com biólogos e ecólogos em problemas específicos. Estudamos alguns modelos espaciais explícitos para dispersão em conexão com estrutura de estágio. Isto inclui um modelo de equaçõesintegrais a diferenças para a invasão de moscas varejeiras no Brasil durante os anos 70, parametrizado com dados tanto de laboratório quanto de campo para prever \emph{a posteriori} a velocidade de invasão, obtendo boa concordância. Também estudamos o fenômeno conhecido como desconexão de \emph{habitat}, em que indivíduos imaturos de espécies com história de vida complexa, tais como anfíbios dependentes de cursos d'água para reproduzir, são fisicamente separados do seu \emph{habitat} adulto, o que aumenta sua mortalidade drasticamente e pode levar a um limiar de extinção. Investigamos ainda um modelo para migração a partir de uma mancha em uma paisagem com forte sazonalidade, onde a dispersão é possível somente durante uma parte do ano, levando a regimes distintos dependendo da duração dessa estação em relação ao tempo característico de difusão na matriz. Atacamos também problemas envolvendo a coexistência de espécies em comunidades, começando com a dinâmica de coexistência de duas espécies relaci... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This thesis broaches the dynamics of structured biological populations. These structures consist of anything that distinguishes individuals of the same population: sex, age, stage, size, spatial location, individual characteristics, etc. We explored a wide range of ecological systems and modeling approaches, working closely with biologists and ecologists in problems arising in specific contexts. We studied some spatially explicit models for dispersal in connection with stage structure. Those include an integrodifference model for a blowfly invasion in Brazil during the 1970s, parametrized with laboratory and reanalyzed field data to predict a posteriori the invasion speed, obtaining a reasonable agreement. We also study the phenomenon known as habitat split, where immature individuals of species with complex life history, such as amphibians dependent on water streams to reproduce, are physically separated from their adult habitat, what can increase their mortality dramatically and lead to sharp extinction thresholds. We also investigate a model for population migration from a patch in a scenario of strong seasonality, where dispersal is possible only during part of the year, leading to distinct scenarios depending on that duration relative to the characteristic time for diffusion into the matrix. Then we look at problems involving coexisting species in communities, beginning with the dynamics and coexistence of two species engaging in intraguild mutualism, in which they are b... (Complete abstract click electronic access below)
Doutor
Dixit, Rashmi. "Influenza in Vulnerable Populations". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/19609.
Pełny tekst źródłaMäki-Petäys, H. (Hannaleena). "Conservation and management of populations in a fragmented forest landscape:behavioural ecology meets population genetics". Doctoral thesis, University of Oulu, 2007. http://urn.fi/urn:isbn:9789514283482.
Pełny tekst źródłaDowning, Beatrice Catherine. "Disruption and disease : how does population management affect disease risk in wild bird populations?" Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/29259.
Pełny tekst źródłaLevin, Alex Ph D. (Alexander) Massachusetts Institute of Technology. "Graphs, matrices, and populations : linear algebraic techniques in theoretical computer science and population genetics". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/83695.
Pełny tekst źródłaCataloged from PDF version of thesis.
Includes bibliographical references (pages 149-155).
In this thesis, we present several algorithmic results for problems in spectral graph theory and computational biology. The first part concerns the problem of spectral sparsification. It is known that every dense graph can be approximated in a strong sense by a sparse subgraph, known as a spectral sparsifier of the graph. Furthermore, researchers have recently developed efficient algorithms for computing such approximations. We show how to make these algorithms faster, and also give a substantial improvement in space efficiency. Since sparsification is an important first step in speeding up approximation algorithms for many graph problems, our results have numerous applications. In the second part of the thesis, we consider the problem of inferring human population history from genetic data. We give an efficient and principled algorithm for using single nucleotide polymorphism (SNP) data to infer admixture history of various populations, and apply it to show that Europeans have evidence of mixture with ancient Siberians. Finally, we turn to the problem of RNA secondary structure design. In this problem, we want to find RNA sequences that fold to a given secondary structure. We propose a novel global sampling approach, based on the recently developed RNAmutants algorithm, and show that it has numerous desirable properties when compared to existing solutions. Our method can prove useful for developing the next generation of RNA design algorithms.
by Alex Levin.
Ph.D.
Kantola, Paula Sisko. "Invasion of Rhizoctonia solani Kühn in host populations : scaling from individual to population behaviour". Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615880.
Pełny tekst źródłaMEMMI, MARC MARIE. "Etude genetique de la population corse et sa relation avec les populations euro-mediterraneennes". Corte, 1999. http://www.theses.fr/1999CORT3043.
Pełny tekst źródłaHuang, Richard. "Spatial variation in Cellana grata populations : the interplay of population dynamics and food availability /". Hong Kong : University of HOng Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23540230.
Pełny tekst źródłaNeal, David R. "Finite difference approximations of advection-diffusion equations for modeling shark populations /". Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-3/neald/davidneal.pdf.
Pełny tekst źródłaOdame, Emmanuel A. "Assessing Heat-Related Mortality and Morbidity Risks in Rural Populations and Sub-Populations". Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3637.
Pełny tekst źródłaArsenault, Julie. "Régionalisation du pool génique québécois : analyse du devenir des gènes fondateurs /". Thèse, Ste-Foy : Chicoutimi : Université Laval. Université du Québec à Chicoutimi, 1999. http://theses.uqac.ca.
Pełny tekst źródłaGuicharnaud, Chloé. "Dynamiques éco-évolutives de la densité-dépendance au sein des fronts d'expansion poussés". Electronic Thesis or Diss., Université Côte d'Azur, 2023. http://www.theses.fr/2023COAZ6041.
Pełny tekst źródłaPopulation density, i.e. the number of individuals present in a given space, has a major influence on individual performance and ultimately population biology. The nearly ubiquitous presence of density-dependence and density-dependent traits within the Tree of Life makes it important to know more about how density-dependence can evolve and influence population dynamics. When a population is expanding over space, density varies dramatically over a short spatial scale from the already occupied, sometimes densely populated, core area to the empty spaces beyond the expanding edge. In this context, understanding how dispersal traits respond to density is essential to know as it will potentially lead to or shape various ecological and evolutionary changes along the expansion. Notably, positive density-dependence in dispersal (but also in population growth rates) can generate so-called "pushed" expansions, where individuals in populations well behind the leading edge mostly drive the spread. Such dynamics are compared to more "pulled" expansions, in which the spread is driven by individuals at the leading edge. Many studies on this pulled/pushed continuum ignore the possibility of an evolving positive density dependence, and how traits driving that density dependence may be correlated with other traits or each other. During this thesis, I combined experimental and simulated expansions to explore how the evolution of correlated density-dependent life-history traits could influence eco-evolutionary dynamics under the lens of pulled/pushed dynamics. First, I demonstrated that among different species of Trichogramma microwasps, each species' position on a pace-of-life continuum was partially correlated with how pushed or pulled the expansion is. Slower species generating more pushed expansions. Then, using an Individual-Based Model, I found, conversely to my expectations, that the strength of life-history trait correlation does not significantly influence overall pulled/pushed dynamics. However, there is evidence that dispersal costs can markedly reshape the relationship between neutral genetic diversity and density-dependence that is key to pushed dynamics. Finally, using simulated expansions again, I attempted to build predictive models that can infer key pushed expansion parameters from a set of metrics based on population genetics or demography that could be easily obtainable from empirical datasets or in the field. Our first proof of concept presented encouraging results, with good model performances when predicting the presence of positive density-dependence in dispersal or the spatial neutral genetic diversity. Overall, this thesis presents the importance of including the evolution of density-dependent traits within studies on pulled versus pushed expansions, as it may result in shifts within this continuum. The (co)evolutionary history also seems to influence how much the expansion is pushed or pulled, but not the correlation structure itself. Indications of divergent evolutionary trajectories between pushed expansions generated by positive density-dependence in dispersal or population growth open the door for further studies on the evolution of biological expansions, and on how to include it to make better predictions in real-life scenarios