Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 16 of 16 for “"Closed population"”.
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Bias in Closed Population Capture-Recapture
… was the effect of departures from assumptions on population estimates obtained using three maximum likelihood population size estimators: M0 (all individuals have the same capture probability on all occasions), Mb (behavior is affected by prior capture) and Mt (all individuals have the same …
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Analysis of Inbreeding in a Closed Population of Crossbred Sheep
… on multiple traits were analyzed in an 11-yr closed population of sheep established in 1983 and remained closed after 1987, with 50% Dorset, 25% Rambouillet, and 25% Finnsheep breeding to determine selection response for spring fertility. The population had been randomly divided in 1987 into a …
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Age Effects on Social and Investigative Behaviors in a Closed Population of African Elephants
In this study of African elephants (Loxodonta africana), I examined two competing hypotheses to explain the development of social and reproductive behaviors. The reproductive hypothesis states that behaviors change around the time when an individual begins successfully reproducing, while the social …
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Patterns of Chemosensory Behavior in a Closed Population of Wild African Elephants (Loxodonta Africana)
… This study examined chemosensory behaviors in a population of African elephants living in Addo Elephant National Park, South Africa and demonstrated that patterns emerge as elephants develop and approach sexual maturity. Older pubescent males (15-19 year olds) performed more chemosensory …
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Parentage analysis in a free-ranging, closed population of southern white rhinoceros : genetics, pedigrees and management
Small populations of animals are vulnerable to the consequences of breeding within a closed group – inbreeding depression and genetic drift lead to reductions in genetic variability, which in turn can give rise to the amplification of deleterious traits. Traditionally, managers attempt to minimise …
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Capturing transients: an application of biostatistics to astronomy
… the underlying size of astrophysical transient populations. In this work, we present a series of exploratory analyses using capture-recapture methods from biostatistics. In the first of three separate analyses, we reproduce results of Laycock (2017). Strategically sampled X-ray lightcurves of …
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Stochastic and Renewal Methods Applied to Epidemic Models
… which analyse the disease spreads within the population in three different settings. The first chapter analyses the effects of the adaptive vaccination strategy on the infectious disease dynamics in a closed population and a demographically open population. The analytical methods are used to …
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Population size estimation from mark-resighting surveys
… consider the problem of estimating the size of a closed population based on the results of a certain type of marking-resighting sampling design. The design is similar to the commonly used multiple capture-recapture design, yet in some cases economically more feasible and easy to use. Sampling is …
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Monarch Butterfly (Danaus plexippus) Tree Preference and Intersite Movement at California Overwintering Sites
… Also, in years when the overwintering population was highest, monarchs clustered disproportionately on native conifers, and they often switched from clustering on eucalyptus in the early winter to native conifers in the middle or late winter. Our results suggest that overwintering …
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Evolutionary Dynamics of Brown Treesnake (Boiga irregularis) Reproductive Ecology, with Implications for Invasive Species Control
… pedigree of BTS in an experimentally-closed population (N = 426). When juxtaposed with ecological data, the pedigree served to: (1) Characterize fundamental aspects of BTS reproductive ecology, (2) quantify selection on traits identified as important for mating and reproduction, (3) …
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Network modelling for sexually transmitted diseases
… disease epidemics. We are interested in a closed population, where infections are only transmitted through heterosexual contacts. The population is hence divided into two groups: male and female. Individuals are classified according to gender, relationship and disease status. Both …
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Genetic analyses of growth, sexual maturation, and ova production in chickens
… (H) and for low (L) 56-day body weight and a closed population of Jersey Black Giants (JJ). F₁ generation crosses (sire listed first) included HL, LH, JL, and JH, and an F₂ generation from HL x HL matings. Comparisons also include dwarf and nondwarf chickens from the H and L lines. Symbols for …
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Genetic variation within the Icelandic goat breed: assessment using population data and DNA analysis
The Icelandic goat breed is a very small closed population consisting of only about 500-600 animals kept in 45 herds. The breed is believed to have originated from Norway during the settlement of Iceland in the years 874-930 AD. Several population bottlenecks are known to have occurred and the …
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Genetic variation within the Icelandic cattle breed: assessment using microsatellites and analysis of single nucleotide polymorphisms in the Leptin and DGAT1 genes
… over 1000 years; therefore it is considered a closed population. Results from the microsatellite analysis revealed a mean number of observed alleles per locus of 6.182, ranging from 4 (ETH3) to 9 (TGLA53) for individual markers. Mean observed and expected heterozygosity were calculated as 0.626 …
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Characterizing maternal and alloparental care in wild killer whales
… (Orcinus orca ater) are a critically endangered, closed population of wild, free ranging cetaceans that have been closely studied by the Center for Whale Research for almost 50 years, with individual identification and maternal relatedness known for every individual. Using drone footage from …
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An Evaluation of Yellow Perch Perca flavescens Mortality in South Dakota
Population dynamics (recruitment, growth, and mortality) of common yellow perch Perca flavescens population types have been previously investigated in South Dakota. Of these dynamic rate functions, mortality is the least understood for yellow perch populations in South Dakota glacial lakes. Total …