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1
Orsi, Maia. "Population synthesis models for IMF studies." Thesis, Liverpool John Moores University, 2014. http://researchonline.ljmu.ac.uk/4525/.
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Population synthesis models (PSMs) are fundamental tools to study the star formation history and IMF of unresolved stellar populations using spectral features. This work presents a new set of PSMs constructed using theoretical isochrones and two state-ofthe- art synthetic spectral libraries. The BT-Settl and Munari libraries were chosen for their ability to predict the observed values of Lick-type and IMF-sensitive indices in individual stars of the solar neighbourhood. The BT-Settl library was used to sample the cool main sequence stars and the Munari library for the rest of the evolutionary phases. The PSMs cover a range of metallicities with [Fe/H]= 0, -1.31 and -1.81 for scaled-solar and α-enhanced metal mixtures. The models were used to study the behaviour of the IMF indices defined in the literature and the results are in good agreement with what other PSMs have determined. The PSMs in this work predict a strong degeneracy between age, metallicity and IMF. I used the models to study which are the main evolutionary phases contributing to each IMF-sensitive index and found that most indices reach their final integrated values before the turn off. The post-main sequence stars contribute mainly to the continuum of these bands. Uncertainties in the the effective temperature of the isochrones can affect IMF estimates. The PSMs were applied to extragalactic globular clusters (GCs) and early-type galaxies (ETGs) using data from the literature. I determined the ages, metallicities and IMFs of these systems using index combinations in the optical and infrared. I explored how the morphology of the Horizontal Branch (HB) and dynamical evolution (which are key uncertainties in the modelling of GCs) can affect the IMF predictions. In a population with a Milky Way IMF, dynamical evolution can make the IMF indices mimic a bottom-light IMF. HB morphology has no impact on the IMF estimates at low [Fe/H]. In the IMF index-index diagrams for GCs, the results are significantly affected by the unknown sodium abundances of these systems. Using the PSMs in this work the best index combination to determine the IMF is CaH1 and TiO2. The ETGs and the [Fe/H]=0 GCs appear to have a bottom-heavy IMF with x ~ 3:0. These results are discussed in the work.
2
Liu, Youfang. "Analytical tools for population-based association studies." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-08182008-161113/.
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Disease gene fine mapping is an important task in human genetic research. Association analysis is becoming a primary approach for localizing disease loci, especially when abundant SNPs are available due to the well improved genotyping technology during the last decades. Despite the rapid improvement of detection ability, there are many limitations of association strategy. In this dissertation, we focused on three different topics including haplotype similarity based test, association test incorporating genotyping error and simulation tool for large data set. 1) Previous haplotype similarity based tests donât have the ability to incorporate covariates in the test. In chapter 2, we proposed a new association method based on haplotype similarity that incorporates covariates and utilizes maximum amount of data information. We found that our method gives power improvement when neither LD nor allele frequency is too low and is comparable under other scenarios. 2) In chapter 3, we proposed a new strategy that incorporates the genotyping uncertainty to assess the association between traits and SNPs. Extensive simulation studies for case-control designs demonstrated that intensity information based association test can reduce the impact induced by genotyping error. 3) In chapter 4, we described simulation software, SimuGeno, which is used to simulate large scale genomic data for case-control association studies.
3
SHENG, XIAOHUA. "HUMAN POPULATION STRATIFICATION AND GENETIC ASSOCIATION STUDIES." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196096932.
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Fraine, Shawn M. "Sexual Victimization of the Transgender Population." Thesis, Southern Illinois University at Edwardsville, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10750694.
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This study examined sexual victimization, resilience, and revictimization in the transgender community. Participants were recruited nationally through targeted Facebook advertising. This study observed that transgender participants were more likely to experience victimization and revictimization when compared to cisgender participants. It was also observed that transgender participants had more positive attitudes toward help-seeking but scored lower on a resilience scale than cisgender and sexual minorities. Implications will be discussed.
5
Spillards, D. M. "Studies of plant competition." Thesis, University of East Anglia, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.232927.
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May, Celia A. "VNTR studies of birds of prey." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358003.
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Rosalie, Michel Wilvene. "Population processes in the Seychelles." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313123.
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Schmidt, Alex Andre. "Stellar population studies in galaxy nuclei : a practical approach to the population synthesis problem." Thesis, University of Sussex, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334676.
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Swenson, Lennart. "Population studies on genetic diseases in the dog /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-5822-6.pdf.
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Weir, William. "Genomic and population genetic studies on Theileria annulata." Thesis, University of Glasgow, 2006. http://theses.gla.ac.uk/3584/.
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Tropical theileriosis, caused by the tick-transmitted protozoan Theileria annulata, is a major disease of cattle in many regions of the developing world. Current research is directed towards developing a sub-unit vaccine, and it is therefore important that genetic diversity in field populations of the parasite is investigated and quantified. The recently completed genome sequence provided an opportunity to develop a panel of genetic markers for population studies and also enabled the identification of novel antigen genes. The genome was bioinformatically screened to identify micro- and mini-satellite loci, several of which were PCR amplified from a series of diverse parasite stocks in order to characterise their polymorphism and to determine their species-specificity. A panel of ten markers were selected for population genetic studies and were used to genotype laboratorymaintained cell lines and clonal stocks of T. annulata isolated from different countries. Cell lines comprised a multiplicity of genotypes, while clonal stocks showed evidence of a single haploid genome. Preliminary population genetic analysis revealed a large amount of genotypic diversity both between and within countries and indicated that the parasite population is geographically sub-structured. Comparison of a limited number of stocks isolated in different countries demonstrated that genetic differentiation between populations positively correlates with intervening physical distance. A low standard index of association (IS A) suggested that the population in Tunisia is in linkage equilibrium, indicating that the parasite possesses a panmictic (randomly mating) population structure. To confirm these findings, a large number of field isolates from Tunisia and Turkey were analysed (n = 305). This supported the earlier finding that geographical sub-structuring separates panmictic populations and an almost identical amount of genetic differentiation between countries was evident (FST = 0.05). Limited linkage disequilibrium was observed in some populations and this was attributed to several factors including inbreeding and the Wahlund effect, caused by putatively immigrant sub-populations. A similar multiplicity of infection was demonstrated in vaccinated and unvaccinated animals and the immunising genotype did not appear to establish in the field population. Multiplicity of infection was instead shown to positively correlate with the host age in several sampling locations. The genome of T. annulata was compared with that of T. parva to identify gene families under the influence of positive selection using mean family inter-genomic nonsynonymous to synonymous substitution rates (dNdS). Codon usage between the species and between several life-cycle stages within T. annulata was shown to be virtually invariant and independent of the dNdS distribution. In addition to a subset of merozoite genes, which were predicted to be antigens on the basis of their motif signature, a subtelomeric gene family (SVSP) and a family of parasite-encoded host nuclear genes (TashATs) showed evidence of positive selection between the species. An allelesequencing approach was taken to verify these predictions which indicated that, in general, the TashAT genes are under the effect of purifying selection while two SVSP genes were shown to be highly variable, however there was no firm evidence of positive selection. One of the merozoite antigen candidates showed evidence of both positive immune selection and balancing selection. Consequently, further studies are indicated to assess whether this gene has value as a vaccine candidate.
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Marsden, Amy. "Population studies of falcons using microsatellite DNA profiling." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395595.
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Wynne, Ian R. "Population studies on farmland insects using genetic markers." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387677.
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Richardson, Katherine. "Studies on the population dynamics of Teladorsagia circumcincta." Thesis, University of Glasgow, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366339.
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Oxtoby, E. P. "Genetic studies in the Greek population of Cyprus." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355478.
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Wright, James Graham. "Population pharmacokinetic & pharmacodynamic studies of chemotherapeutic agents." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403581.
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Venkataraman, Archana Ph D. Massachusetts Institute of Technology. "Generative models of brain connectivity for population studies." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78534.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 131-139).
Connectivity analysis focuses on the interaction between brain regions. Such relationships inform us about patterns of neural communication and may enhance our understanding of neurological disorders. This thesis proposes a generative framework that uses anatomical and functional connectivity information to find impairments within a clinical population. Anatomical connectivity is measured via Diffusion Weighted Imaging (DWI), and functional connectivity is assessed using resting-state functional Magnetic Resonance Imaging (fMRI). We first develop a probabilistic model to merge information from DWI tractography and resting-state fMRI correlations. Our formulation captures the interaction between hidden templates of anatomical and functional connectivity within the brain. We also present an intuitive extension to population studies and demonstrate that our model learns predictive differences between a control and a schizophrenia population. Furthermore, combining the two modalities yields better results than considering each one in isolation. Although our joint model identifies widespread connectivity patterns influenced by a neurological disorder, the results are difficult to interpret and integrate with our regioncentric knowledge of the brain. To alleviate this problem, we present a novel approach to identify regions associated with the disorder based on connectivity information. Specifically, we assume that impairments of the disorder localize to a small subset of brain regions, which we call disease foci, and affect neural communication to/from these regions. This allows us to aggregate pairwise connectivity changes into a region-based representation of the disease. Once again, we use a probabilistic formulation: latent variables specify a template organization of the brain, which we indirectly observe through resting-state fMRI correlations and DWI tractography. Our inference algorithm simultaneously identifies both the afflicted regions and the network of aberrant functional connectivity. Finally, we extend the region-based model to include multiple collections of foci, which we call disease clusters. Preliminary results suggest that as the number of clusters increases, the refined model explains progressively more of the functional differences between the populations.
by Archana Venkataraman.
Ph.D.
17
Olsson, Sven Johan Gustav. "Studies of physical activity in the Swedish population." Doctoral thesis, Gymnastik- och idrottshögskolan, GIH, Björn Ekbloms och Mats Börjessons forskningsgrupp, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-4309.
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Background: Cheap and effective tools for measuring patients’ physical activity (PA) level are needed. The first aim in this thesis was therefore to assess the validity of two PA -questions, and their three associated answer modes, that are used within the Swedish health care system. Sitting, light intensity PA (LIPA), and moderate and vigorous intensity PA (MVPA), are associated with health and longevity, but detailed population data assessed with objective methods is needed. The second aim was thus to assess the above with motion sensor technology, in a middle-aged Swedish sample. Low self-perceived health is a strong predictor of morbidity and mortality, but this association may vary over time with changes in the society and our lifestyle. The third aim was to assess secular trends in the interrelations between self-perceived health, physical fitness, and selected covariates. The effects of PA on prescription (PAP) on health-related quality of life (HRQoL) in overweight adults are unclear, thus the fourth aim was to explore this. Methods: All data was collected in the Swedish population. Data from the PA -questions and accelerometers, aerobic fitness, counter movement jump, and balance tests, blood samples, and self-rated general health were collected in 365 participants, 21–66 yrs. The PA pattern was assessed in 948 individuals, 50‒64 yrs, from the SCAPIS pilot study. Self-perceived physical health, and measured aerobic fitness, counter movement jump height, and balance, and demographic and lifestyle data, was assessed in three independent samples from 1990, 2000 and 2013, including 3564 adults, 20‒65 yrs. The effects of Swedish PAP on HRQoL was assessed in a randomized controlled trial including 101 men and women, 67‒68 yrs, that were inactive, overweight (BMI>25 kg/m2), and had a waist circumference ≥102 cm (men) or ≥88 cm (women), who were randomized to an intervention group or a control group. The 36-item Short Form Health Survey (SF-36) was used to assess HRQoL. Results: The multiple choice answer mode of the two PA -questions was found to have the strongest validity, compared with the two other (an open mode, and one where PA minutes is specified per weekday). The validity is in line with many other established PA-questionnaires, but the open mode has limitations. The assessment of PA pattern showed that 61% of motion sensor wear time represented sitting, 35% LIPA, and 4% MVPA. Only 7% of the sample met the PA recommendations. The odds for describing perceived health as good was found to increase by 5% per each increment of 1 ml/kg/min in VO2max. This was stable across genders and all three LIV-samples (i.e. over time). Waist circumference, chronic disease, sleep problems, and level of satisfaction with one’s life, were also important correlates. The Swedish PAP group improved significantly more, and more participants displayed clinically relevant improvements (OR 2.43), in mental aspects of HRQoL, compared to the controls. Physical aspects of HRQoL improved in the PAP group, but not in the control group. Conclusions: The multiple choice answer mode has the strongest validity and Open mode the weakest. The PA -questions may be used in populations, or in individuals to determine appropriateness for treatment. The questions’ advantages and limitations must be considered and further reliability and validity studies are needed. The results regarding sitting, LIPA, MVPA and fulfillment of PA recommendations, are of high clinical relevance. A great challenge remains to further implement methods to increase the level of PA in the Swedish population. Physical fitness is related to self-perceived health independently of changes in society and lifestyle over time, and simple questions may be useful for the clinical assessment of physical fitness. Swedish PAP has a positive effect on mental aspects of HRQoL, measured by the SF-36. This finding supports the clinical use of the Swedish PAP model.LIV 2013
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Abadi, Fariborz Jafari Rahmat. "Population genetic and epidemiological studies of Neisseria meningitidis." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU089864.
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The population structure of Neisseria meningitidis was investigated by MLEE and REA. Using MLEE 107 strains were characterised studying 6 loci. Clones were defined as 5 loci were identical in the strains studied. Seventy two strains fell into twenty six multimember clones. The clones identified contained between 2 and 6 members. The remaining (n=35) strains were regarded as unique. The genetic diversity of the population was estimated as 0.700. This high degree of diversity seems to be because the majority of the strains were isolated from sporadic cases. Isolates within multimember clones contain isolates of outbreaks and sporadic cases. Clones were also identified in a collection of serogroup C. Neisseria meningtidis (n=34) strains by REA using endonuclease StuI. Eleven multimember clones were recognised containing between 2 and 15 members. Seven strains were regarded as unique. The largest multimember clone (n=15) contained 6 rifampicin resistant meningococci and also strains sensitive to rifampicin. This finding seems to be in the favour of this hypothesis that the resistant phenotype arose once and spread through the United Kingdom. Similarly matrices between 11 serogroup C and 5 serogroup B meningococcal strains were determined. The extensive Dice similarity coefficient between strains of serogroup C and B and also close genetic distance between these two serogroups, on the one hand, and very low Dice similarity coefficient (>50%) and distant genetic relations between serogroups C meningococcal isolates, on the other, demonstrated serogrouping cannot be regarded as a reflection of overall genetic similarity; although its practicality in epidemics and its convenience renders it useful as a first step in hierarchical typing system.
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Andersson, H. Ingemar. "Chronic pain epidemiological studies in a general population /." Lund : Dept. of Community Health Services, Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/40178010.html.
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Bolton, Damien Michael. "Whole-of-population based studies In urologic cancer." Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17066.
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Since Prostate Specific Antigen testing became commercially available prostate cancer has transformed from a clinically diagnosed often advanced disease usually in elderly men, to a biochemically detected usually organ confined condition which more often affects younger males. This resulted in a major shift in the patterns of care of prostate cancer from an observant, pharmaceutical therapy dominated algorithm, to surgically directed management via radical prostatectomy. This transition initially was undertaken on the basis of logic but with little conclusive evidence to support this change. It was this major adjustment in practice that was the impetus for this thesis. Few prospectively established whole-of–population registries of patients undergoing radical prostatectomy had been established at the time this project was conceived. The aim of this project was to follow sequentially for a 10 year period the progress of all men treated by radical prostatectomy in the state of Victoria, with a view to determining the likelihood of progression to objective biochemical and clinical benchmarks in the future. Multiple publications were derived from this registry, and from projects that have arisen as a consequence of the existence of the central database. Outcomes identified include the very low risk of prostate cancer specific mortality (PCSM) even after biochemical recurrence, especially in men with lower risk prostate cancer at diagnosis, and that predictors of PCSM independent of tumour stage and grade included rural residency of patients (p=.003), involvement of a trainee surgeon in the operation (p=.014), presentation with voiding symptoms rather than on the basis of an elevated PSA level, and the primary surgeon contributing less than 40 cases (low volume) to the VRPR (p=.024). As a consequence of the existence of our whole of population based registry of radical prostatectomy for prostate cancer the implications became apparent for patients of having a strong family history of breast cancer and of being a carrier of one or more variants of the BRCA gene. Extension of this concept resulted in a series of all men treated by High Intensity Focused Ultrasound (HIFU) upon its introduction in the state of Victoria, and a patterns of practice study of all patients in this state undergoing surgery for renal cell carcinoma.
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Channon, David. "Behavioural and population studies of sewer rats (Rattus norvegicus)." Thesis, University of Surrey, 2008. http://epubs.surrey.ac.uk/842995/.
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This study aimed to: (1) Establish if rodent populations in sewers are separate from surface ones (Sewer Interceptor study) (2) Investigate the numbers and distribution of rats in sewers (Preferred Location study/Long term study/Hot spot study) (3) Identify Rat behaviours that might affect numbers and control measures (Bait trial / Preferred Location study). To achieve these aims sewer rat populations were monitored in the London sewer systems over a 20-year period. More detailed studies on rat behaviour were carried out in sequestered sewer systems. The Interceptor study showed that rats are not confined in the system by water traps and cannot be viewed as a separate population from surface rats. They can, especially during periods of low flow, swim underwater, upstream, in the dark, to access or exit the system. The Preferred Location study showed that rats like to find and use dry locations within the sewer network. There are distinct sets of behaviours, which occur in dry locations and not in wet ones and vice versa. The Bait trial confirmed other studies showing that sewer rats are neophobic and this factor needs to be taken into account when dealing with them. The more rats there were, the shorter the avoidance period. In the experiment here, the mean time until consumption decreased from 8.5 for one rat to 5.5 days for three rats. The Long Term study found that the trend in rat numbers has been in decline over the whole twenty-year period of the study in the location studied. In the first thirteen years of the study, the proportion of bait takes decreased significantly from approximately 0.17 in 1986/87 to 0.03 in 1998/99 (F=17.75, P < 0.001: df 1,11). Since then, the decline has continued with an exponential curve best fitting the data. The Hot Spot study showed that Rats are not evenly distributed throughout the sewer network but occur, year on year in "Hotspots". These were locations, which showed up to 17 times more than the statistically significant level of rodent activity. This activity occurred in the same location year after year although not throughout the entire study period. These locations were statistically significant (p < 0.0001 after using the Bonferroni correction).
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Wang, Yean. "Molecular polymorphisms for phylogeny, pedigree and population structure studies." University of Sydney, 2007. http://hdl.handle.net/2123/1541.
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Doctor of PhilosophyA number of types of molecular polymorphisms can be used for studying genetic relationship and evolutionary history. Microsatellites are hypervariable and can be very useful tools to determine population structure, distinguish sibling species, as well as verifying parental relationships and pedigrees. However, while microsatellite polymorphisms are useful for solving relationships between populations within a species, relations among species or genera will probably be obscured due to a high degree of homoplasy —identity arising from evolutionary convergence not by descent. For long range evolutionary history, such as phylogeny from old world monkey to human, mtDNA markers may be better candidates. The aim of this thesis is to assess molecular polymorphisms of different types and their optimal use in different situations. Two widely separated taxa were used for testing –the green monkey Chlorocebus sabaeus, and the sibling dipteran flies Bactrocera tryoni and B. neohumeralis, known collectively as the Queensland fruit fly. In the present study a complete 16,550 bp mtDNA sequence of the green monkey Chlorocebus sabaeus is reported for the fist time and has been annotated (Chapter 2). Knowledge of the mtDNA genome contributes not only to identification of large scale single nucleotide polymorphisms (SNPs) (Chapter 4) or other mtDNA polymorphisms development, but also to primate phylogenetic and evolutionary study (Chapter 3). Microsatellites used for the green monkey paternity and pedigree studies were developed by cross-amplification using human primers (Chapter 5). For studies of population structure and species discrimination in Queensland fruit fly (Chapter 7), microsatellites were isolated from a genomic library of Bactrocera tryoni (Chapter 6) The total length of 16550 bp of complete mtDNA of the green monkey C. sabaeus, which has been sequenced and annotated here, adds a new node to the primate phylogenetic tree, and creates great opportunity for SNP marker development. The heteroplasmic region was cloned and five different sequences from a single individual were obtained; the implication of this are discussed. The phylogenetic tree reconstructed using the complete mtDNA sequence of C. sabaeus and other primates was used to solve controversial taxonomic status of C. sabaeus. Phylogenies of primate evolution using different genes from mtDNA are discussed. Primate evolutionary trees using different substitution types are compared and the phylogenetic trees constructed using transversions for the complete mtDNA were found close to preconceived expectations than those with transversions + transitions. The sequence of C. sabaeus 12SrRNA reported here agrees with the one published by ven der Kuyl et al. (1996), but additional SNPs were identified. SNPs for other regions of mtDNA were explored using dHPLC. Twenty two PCR segments for 96 individuals were tested by dHPLC. Fifty five SNPs were found and 10 haplogroups were established. Microsatellite markers were used to construct a genealogy for a colony of green monkeys (C. sabaeus) in the UCLA Vervet Monkey Research Colony. Sixteen microsatellites cross-amplified from human primers were used to conduct paternity analysis and pedigree construction. Seventy-eight out of 417 offspring were assigned paternity successfully. The low success rate is attributed to a certain proportion of mismatches between mothers and offspring; the fact that not all candidate fathers were sampled, the limitations of microsatellite polymorphisms; and weakness of the exclusion method for paternity assessment. Due to the low success rate, the pedigree is split into a few small ones. In a complicated pedigree composed of 75 animals and up to four generations with multiple links a power male mated with 8 females and contributed 10 offspring to the pedigree. Close inbreeding was avoided. Population structure within two species of Queensland fruit fly Bactrocera tryoni and Bactrocera neohumeralis (Tephritidae: Diptera) is examined using microsatellite polymorphisms. Queensland fruit flies B. tryoni and B. neohumeralis are sympatric sibling species that have similar morphological and ecological features. They even share polymorphism at the molecular level. Mating time difference is the main mechanism by which they maintain separate species. In the present study, 22 polymorphic and scorable microsatellites were isolated from B. tryoni and tested in the two species sampled from sympatric distribution areas. Pairwise genetic distance analysis showed explicit differentiation in allele frequencies between the two species, but very weak differences between conspecific populations. Gene flow is higher within B. tryoni than within B. neohumeralis, and gene exchange between the two species exists. An averaging linkage clustering tree constructed by UPGMA showed two major clusters distinguishing the two species, and it appears that population structure is highly correlated with geographic distance. The relationship between molecular markers, evolution, and selection are discussed using comparative studies within two large taxa: primate and insect. The degree of conservation and polymorphism in microsatellites varies between taxa, over evolutionary time.
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Berry, Dean B. "Case studies of emergent literacy in a special population." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0001/NQ38776.pdf.
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Hume, Jennifer C. C. "Transmission studies and population structure in human malaria parasites." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409801.
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Jenner, D. A. "Population studies of variation in catecholamine and corticosteroid excretion." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371675.
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Astle, William John. "Population Structure and Cryptic Relatedness in Genetic Association Studies." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505314.
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Skidmore, Paula Marie Louise. "Diet and cardiovascular risk : population studies in Northern Ireland." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342981.
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Greipsson, Sigurdur. "Population studies on the dune-building grass Leymus arenarius." Thesis, University of East Anglia, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303369.
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Hubbard, C. E. "Population studies of Spartina angelica in the Dee Estuary." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381195.
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Sweetman, Stephen John. "Population balance modelling and experimental studies of emulsion polymerisation." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/7430.
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Emulsion polymerisation is a process of considerable technological and industrial significance. The process presents many challenges in respect to design, optimisation and multi-objective distribution control. The quality of latex is determined by the final product properties, Le. viscosity, mechanical strength and film-forming ability, which are in turn a function of the latex attributes of PSD and MWD. This motivates an inferential control scheme utilising these distributions. This research addresses model development and controllability analysis towards model-based control. A population balance model for PSD and MWD is developed. The PSD information is incorporated via a one-dimensional population distribution of the polymer particles with respect to their size, in conjunction with a population distribution of the total live polymer radicals/particle. MWD information is incorporated via one-dimensional population distributions of the live radicals and dead polymer chains with respect to their length (in different sized particles). The model solution is facilitated by a number of algorithmic developments, including a decomposition algorithm coupled with a multi-level discretisation for PSD and the application of the method of moments for MWD. This model is compared to extensive experimental data for its validation. Improvements in the form of a twodimensional version of this model enable better prediction of compartmentalisation and hence the growth rates, thereby improving model match with experiments. This work presents a study into the simultaneous controllability of PSD and MWD, assessed through an experimental sensitivity analysis on the main process manipulations: initiator, eTA, monomer and surfactant. The work analyses the practical limitations on the attainability of PSD and MWD. The range of experiments carried out clearly indicates the operation of individual mechanisms in the simultaneous formation of PSD and MWD.
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Sousa, Valderês Aparecida de. "Population genetic studies in Araucaria angustifolia (Bert.) O. Ktze. /." Göttingen : Cuvillier, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=012909852&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Parker, Heidi Gayle. "Advancing canine genomics : from map building to population studies /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5004.
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Wang, Yean. "Molecular polymorphisms for phylogeny, pedigree and population structure studies." Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/1541.
Full textAbstract:
A number of types of molecular polymorphisms can be used for studying genetic relationship and evolutionary history. Microsatellites are hypervariable and can be very useful tools to determine population structure, distinguish sibling species, as well as verifying parental relationships and pedigrees. However, while microsatellite polymorphisms are useful for solving relationships between populations within a species, relations among species or genera will probably be obscured due to a high degree of homoplasy —identity arising from evolutionary convergence not by descent. For long range evolutionary history, such as phylogeny from old world monkey to human, mtDNA markers may be better candidates. The aim of this thesis is to assess molecular polymorphisms of different types and their optimal use in different situations. Two widely separated taxa were used for testing –the green monkey Chlorocebus sabaeus, and the sibling dipteran flies Bactrocera tryoni and B. neohumeralis, known collectively as the Queensland fruit fly. In the present study a complete 16,550 bp mtDNA sequence of the green monkey Chlorocebus sabaeus is reported for the fist time and has been annotated (Chapter 2). Knowledge of the mtDNA genome contributes not only to identification of large scale single nucleotide polymorphisms (SNPs) (Chapter 4) or other mtDNA polymorphisms development, but also to primate phylogenetic and evolutionary study (Chapter 3). Microsatellites used for the green monkey paternity and pedigree studies were developed by cross-amplification using human primers (Chapter 5). For studies of population structure and species discrimination in Queensland fruit fly (Chapter 7), microsatellites were isolated from a genomic library of Bactrocera tryoni (Chapter 6) The total length of 16550 bp of complete mtDNA of the green monkey C. sabaeus, which has been sequenced and annotated here, adds a new node to the primate phylogenetic tree, and creates great opportunity for SNP marker development. The heteroplasmic region was cloned and five different sequences from a single individual were obtained; the implication of this are discussed. The phylogenetic tree reconstructed using the complete mtDNA sequence of C. sabaeus and other primates was used to solve controversial taxonomic status of C. sabaeus. Phylogenies of primate evolution using different genes from mtDNA are discussed. Primate evolutionary trees using different substitution types are compared and the phylogenetic trees constructed using transversions for the complete mtDNA were found close to preconceived expectations than those with transversions + transitions. The sequence of C. sabaeus 12SrRNA reported here agrees with the one published by ven der Kuyl et al. (1996), but additional SNPs were identified. SNPs for other regions of mtDNA were explored using dHPLC. Twenty two PCR segments for 96 individuals were tested by dHPLC. Fifty five SNPs were found and 10 haplogroups were established. Microsatellite markers were used to construct a genealogy for a colony of green monkeys (C. sabaeus) in the UCLA Vervet Monkey Research Colony. Sixteen microsatellites cross-amplified from human primers were used to conduct paternity analysis and pedigree construction. Seventy-eight out of 417 offspring were assigned paternity successfully. The low success rate is attributed to a certain proportion of mismatches between mothers and offspring; the fact that not all candidate fathers were sampled, the limitations of microsatellite polymorphisms; and weakness of the exclusion method for paternity assessment. Due to the low success rate, the pedigree is split into a few small ones. In a complicated pedigree composed of 75 animals and up to four generations with multiple links a power male mated with 8 females and contributed 10 offspring to the pedigree. Close inbreeding was avoided. Population structure within two species of Queensland fruit fly Bactrocera tryoni and Bactrocera neohumeralis (Tephritidae: Diptera) is examined using microsatellite polymorphisms. Queensland fruit flies B. tryoni and B. neohumeralis are sympatric sibling species that have similar morphological and ecological features. They even share polymorphism at the molecular level. Mating time difference is the main mechanism by which they maintain separate species. In the present study, 22 polymorphic and scorable microsatellites were isolated from B. tryoni and tested in the two species sampled from sympatric distribution areas. Pairwise genetic distance analysis showed explicit differentiation in allele frequencies between the two species, but very weak differences between conspecific populations. Gene flow is higher within B. tryoni than within B. neohumeralis, and gene exchange between the two species exists. An averaging linkage clustering tree constructed by UPGMA showed two major clusters distinguishing the two species, and it appears that population structure is highly correlated with geographic distance. The relationship between molecular markers, evolution, and selection are discussed using comparative studies within two large taxa: primate and insect. The degree of conservation and polymorphism in microsatellites varies between taxa, over evolutionary time.
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Morgan, Lee W. "Allozyme Analysis of Billfish Population Structure." W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539617645.
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Kline, Lisa L. "Population dynamics of young-of-the-year striped bass, Morone saxatilis, populations, based on daily otolith increments." W&M ScholarWorks, 1990. https://scholarworks.wm.edu/etd/1539616719.
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Validation of daily increment deposition in otoliths of juvenile striped bass up to 80 days of age was provided through sequential sacrifice of known age hatchery-reared fish in 1987 and 1989, and through tetracycline marking of otoliths of cage-cultured striped bass in 1989. Ages of fish between 80-110 days old were consistently underestimated by 1-3 growth increments. Known age juvenile striped bass were raised in the laboratory in 1989 under controlled environmental conditions. These experiments provided evidence of an endogenous circadian rhythm controlling daily increment deposition in juvenile striped bass otoliths. Juvenile striped bass were collected in the 4 Virginia river systems in 1986 and 1987. A total of 542 otoliths were aged using daily growth increments. Comparisons of back-calculated birthdate distributions between populations showed consistency between rivers within years, but not between years. Variations in cohort growth rates appeared to be related to the relative cohort size of fish surviving to the juvenile stage. A comparison of mortality for 14-day cohorts showed no trends between early and late hatched fish, and no relationship was found mortality and average growth rates for these cohorts. Population growth rates for the period June-September were linearly modelled, and ranged from 0.301-0.597 mm/day and 0.027-0.124 g/day. Mortality estimates for 60-90 day old striped bass ranged from 1.88-3.98% loss/day. Catch-per-unit-effort, as measured as the number of fish per seine haul, ranged from 4.0-29.6. Growth rates in both length and weight were positively correlated with condition factor and stomach fullness, suggesting food availability may play an important role in regulating juvenile striped bass growth. There was no apparent relationship between growth and CPUE. The relationships between growth and mortality, and mortality and CPUE, are ambiguous, and more estimates are needed to determine whether a density-dependent effect is controlling year-class strength and recruitment into the juvenile stage.
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Bamford, Margaret. "Aspects of health among an employed population." Thesis, Aston University, 1993. http://publications.aston.ac.uk/10867/.
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This survey collected information on aspects of health amongst an employed population, employees in 14 different organisations in the West Midlands Regional Health Authority; and was a stratified sample of senior managers, middle managers and operatives. Nine hundred and sixty questionnaires were distributed asking for both quantitative and qualitative information on 58 questions covering health, work, family, leisure activities and life-style. A response rate of 48% (459 returned questionnaires) came from 290 men (63%), 165 women (36%) and four people (1%) who did not answer the gender question. The initial findings from this study are unique in that there has not been a specific review of the health of people at work. In answer to the main research questions, 92% felt they were healthy. Compared to others of a similar age, 34% felt their health was `above average', 58% `average', and 7&37 `below average'. Thirty two percent of respondents had visited their GP in the past 1-2 months; the highest reason given was disorders of the respiratory system, 20%. People's perceptions on the effects of work on their health were: good effect, 13% fair effect, 20% no effect, 27% poor effect, 27% and bad effect, 7%. The effects of leisure activities on health were thought to be more positive: good effect, 46% fair effect, 20% no effect, 21% poor effect, 3% and bad effect, 2%. The perceptions of effects of life-style on health were considered to be: good effect, 32% fair effect, 32% no effect, 20% poor effect, 9% and bad effect, 1%. In this survey, leisure and life-style were seen by employees to have more beneficial effects on health than work. Future implications include a review of occupational health as a major policy development area within primary care. There is a need to influence the education and training of health care practitioners in order to affect their ability to practise effectively in this new and challenging area of work.
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Li, Neville. "Securitisation of population dynamics in the People's Republic of China." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760944.
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As Kingsley Davis stated, ‘the study of population offers one of the unique and indispensable approaches to an understanding of world affairs’ (Davis 1954, p.vii). In the discipline of International Relations, valuable security and political implications have been yielded by examining how population growth constitutes violent conflicts in traditional security studies (e.g. Choucri 1974; North and Choucri 1971). Non-traditional security (NTS) also develops its own problem-solving approach, e.g. human security, to solve demographic-related issues encountered by humankind such as famine and unemployment (UNDP 1994). Despite both traditional and NTS studies having established their material approaches, the ideational relationship between security and population dynamics has yet to be studied in detail. Specifically, this dissertation examines how ideational relationship is/can be established by ‘securitising’ population dynamics, i.e. how to rhetorically make population dynamics a security threat. The thesis adopted a combined analytical framework of the Copenhagen School and the Paris School in the case of the People’s Republic of China (PRC) to identify how the ideational relationship between security and population dynamics was established. It first adopts the securitisation framework to examine how the PRC rhetorically constructed population growth as a security threat and introduced its emergency measure, i.e. the one-child policy. The dissertation then reveals the politics of the prolonged securitisation by evaluating the one-child policy as a technique for governmentality of unease and demonstrates how this constitutes the shift from securitising population growth to population decline. This dissertation argues that population dynamics can be constructed as (the cause of) numerous security threats through a successful securitisation. With the case of the PRC, the thesis demonstrates the de facto politicisation of population growth before the late 70s, and how the de jure securitisation was adopted in a Communist manner to legitimise the world’s strictest population policy, i.e. the one-child policy, as its emergency measure to solve various existential threats posed by population dynamics. In addition, the study of politics of securitisation in the case of the PRC further unfolds the struggles of priorities among different actors, which brings us political, practical and relational implications about this governmentality of unease that lasted for almost 4 decades. A deeper understanding of how our ideas of demography shape what we call ‘security threats’ sheds lights on how states formulate comprehensive security agendas by taking population dynamics into account due to its immense importance to threat construction. Other security actors such as international organisations, private sectors, and even individuals can more easily convince relevant audiences to legitimise the securitisation of the specific demographic-related threats they are facing. As Sciubba put it, ‘population dynamics could be a challenge or an opportunity’ (Sciubba 2011, p.3). Accumulating knowledge of the ideational connections between security and population dynamics increases the ability of various security actors to confront these challenges through a successful securitisation, which contribute to preventing numerous demographic-related threats from happening or at least easing these pains of humankind.
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Kitsikis, Agis. "Theoretical AGB and post-AGB Models for Synthetic Population Studies." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-84271.
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Coggins, Ronald Paul. "DNA mismatch repair in population-based studies of colorectal cancer." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418723.
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Rai, Sharan Kimberly. "Population-based epidemiologic studies of gout in British Columbia, Canada." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59088.
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Introduction: This thesis contains original analyses aimed at better understanding the burden of gout, an excruciatingly painful form of inflammatory arthritis, in the Canadian context. While gout is increasingly recognized as the most common form of inflammatory arthritis worldwide (e.g., reported prevalence of 3.9% and 2.5% in the United States and United Kingdom, respectively), no Canadian trend data are available. Objectives: 1) To evaluate the contemporary prevalence and incidence of gout over the past decade, as well as gout treatment patterns and comorbidity burden. 2) To evaluate the burden of hospitalized gout and corresponding inpatient costs as compared to rheumatoid arthritis (RA), another inflammatory joint disease known to incur substantial resource use. Methods: To address both objectives, I used PopulationData BC, a large administrative database spanning the province of British Columbia (BC). For Objective 1, I used physician and hospital visits to identify gout cases and estimate the annual trends in prevalence and incidence among the general population. I additionally used data from PharmaNet, BC’s prescription drug database, to examine gout treatment patterns (i.e., urate-lowering therapy, colchicine, glucocorticoids, and non-steroidal anti-inflammatory drugs) over the same time period. For Objective 2, I used hospital diagnoses and procedure codes to assess annual trends in hospitalizations and joint surgeries as well as inpatient costs for both gout and RA. Results: 1) Both the prevalence and incidence of gout have increased over the past decade (i.e., a 59% and 48% increase, respectively), while the prescription of gout treatment remains low. 2) The hospitalization rates for gout have doubled over the past decade, while those for RA have declined by 49%. The inpatient costs also reflected the hospitalization trends, with a 40% decrease in RA hospital costs, while gout costs more than doubled over the study period. Conclusion: Altogether, this thesis provides evidence that the burden of gout in Canada is substantial and increasing. These findings are further contrasted against the hospitalization burden of RA, which has decreased considerably over the same period. This thesis highlights the critical need to improve gout prevention and care to mitigate its rising disease burden in Canada and beyond.Medicine, Faculty of
Experimental Medicine, Division of
Medicine, Department of
Graduate
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Mina, Kym Deanne. "Measurement of fish consumption in population-based studies of cancer." University of Western Australia. School of Population Health, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0093.
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[Truncated abstract] The role of fish consumption and omega-3 polyunsaturated fatty acids (PUFAs) in the prevention of disease has been the subject of much investigation in recent years. A clue that these factors might be of importance was the observation that populations consuming high levels of marine omega-3 PUFAs had lower rates of morbidity and mortality from cardiovascular disease. From there, research in this area has expanded to include a range of chronic diseases and their prevention. An area of particular interest is the role of fish consumption in the prevention of various cancers. In Australia, one in three men and one in four women are expected to be diagnosed with cancer by the age of 75. Identifying preventive factors that can be translated into constructive health promotional messages is of great importance in addressing this group of diseases that has such a large impact on the health and wellbeing of the population. ... Results and conclusions Analysis of the data from the population-based case-control study suggests a protective effect of preserved fish consumption, possibly due to the high oil content of these fish. The developed questionnaire is a valid and reliable tool for measuring fish and seafood consumption as determined by regression analysis with an independent biomarker and reliability analysis using intra-class correlation. Importantly, reliability can be maintained despite asking a high level of detail from participants. For ranking according to overall fish consumption, detailed questioning is probably not necessary, however inclusion of variables representing multiple categories of fish and seafood consumption in a regression model enables us to better account for variation in blood omega-3 PUFA levels than a single variable representing overall consumption. For the purpose of questionnaire validation, plasma phospholipid and erythrocyte membrane levels of EPA and DHA are equivalent biomarkers of fish and seafood consumption. The choice between them by future investigators will be based on more practical aspects such as convenience and the fasting state of subjects. The tangible product of this thesis is additional evidence to support a protective association between fish consumption and prostate and breast cancers, and a valid and reliable questionnaire v for measuring habitual consumption of fish and seafood in a West Australian population, that could also be applied to other populations after minor adjustment for local fish and seafood consumption patterns.
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Okori, Patrick. "Population studies of Cercospora zeae-maydis and related Cercospora fungi /." Uppsala : Plant Biology and Forest Genetics, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a468.pdf.
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Kitsikis, Agis. "Theoretical AGB and post-AGB models for synthetic population studies." kostenfrei, 2007. http://edoc.ub.uni-muenchen.de/8427/.
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Wang, Yean. "Phylogeny, pedigree, and population structure studies application of molecular polymorphisms." Saarbrücken VDM Verlag Dr. Müller, 2007. http://d-nb.info/98875634X/04.
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Powers, James Murray. "Population-averaged models for diagnostic accuracy studies and meta-analysis." Thesis, The University of North Carolina at Chapel Hill, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3562789.
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Modern medical decision making often involves one or more diagnostic tools (such as laboratory tests and/or radiographic images) that must be evaluated for their discriminatory ability to detect presence (or absence) of current health state. The first paper of this dissertation extends regression model diagnostics to the Receiver Operating Characteristic (ROC) curve generalized linear model (ROC-GLM) in the setting of individual-level data from a single study through application of generalized estimating equations (GEE) within a correlated binary data framework (Alonzo and Pepe, 2002). Motivated by the need for model diagnostics for the ROC-GLM model (Krzanowski and Hand, 2009), GEE cluster-deletion diagnostics (Preisser and Qaqish, 1996) are applied in an example data set to identify cases that have undue influence on the model parameters describing the ROC curve. In addition, deletion diagnostics are applied in an earlier stage in the estimation of the ROC-GLM, when a linear model is chosen to represent the relationship between the test measurement and covariates in the control subjects. The second paper presents a new model for diagnostic test accuracy meta-analysis. The common analysis framework for the meta-analysis of diagnostic studies is the generalized linear mixed model, in particular, the bivariate logistic-normal random effects model. Considering that such cluster-specific models are most appropriately used if the model for a given cluster (i.e. study) is of interest, a population-average (PA) model may be appropriate in diagnostic test meta-analysis settings where mean estimates of sensitivity and specificity are desired. A PA model for correlated binomial outcomes is estimated with GEE in the meta-analysis of two data sets. It is compared to an indirect method of estimation of PA parameters based on transformations of bivariate random effects model parameters. The third paper presents an analysis guide for a new SAS macro, PAMETA (Population-averaged meta-analysis), for fitting population-averaged (PA) diagnostic accuracy models with GEE as described in the second paper. The impact of covariates, influential clusters and observations is investigated in the analysis of two example data sets.
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Reid, Tracey J. S. "Obsessions and compulsions : electrophysiological studies in a non-clinical population." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282300.
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Bain, Stephen Charles. "The genetics of type 1 diabetes : family and population studies." Thesis, University of Birmingham, 1994. http://etheses.bham.ac.uk//id/eprint/35/.
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Type 1 (insulin-dependent) diabetes mellitus is caused by autoimmune destruction of insulin-producing pancreatic ß-cells. Genetic susceptibility is necessary for the development of type 1 diabetes but inheritance does not follow simple Mendelian rules and environmental factors are also involved. Identification of the genes which mediate disease susceptibility should allow recognition of individuals at high risk of disease; this will facilitate the study of environmental factors and possibly the development of strategies for prevention. Further, the characterisation of susceptibility genes will allow a greater understanding of the aetiopathogenesis of type 1 diabetes and may lead to new therapeutic approaches. A major limiting factor, hindering the genetic dissection of type 1 diabetes, has been the lack of a large well-characterised clinical resource for study. This thesis describes how I have established a Repository of immortalised cell lines from large numbers of ethnically matched controls, sporadic type 1 diabetics and type 1 diabetic multiply affected families. The family resource is now the largest single collection of it's kind and is used by research groups throughout the world. Using this resource, I have further characterised HLA-mediated susceptibility to Type 1 diabetes, particularly with regard to age-related heterogeneity and inherited susceptibility. In addition, I have confirmed the existence of linkage of type 1 diabetes to a gene (or genes) within the insulin gene region on chromosome 11p. I have also performed association studies using other candidate genes. These studies have led to a significant advance in the field of the genetics of type 1 diabetes and bequeath a permanent resource for future research.
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Blanchet, Peggy D. C. "Mercury in hair : method development and application to population studies." Thesis, Sheffield Hallam University, 1996. http://shura.shu.ac.uk/19358/.
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As part of the Avon Longitudinal Study of Pregnancy And Childhood, the toxic metal, mercury, is studied in order to assess whether it presents a danger to the development of children in the UK.The development and optimisation of a digestion procedure for the determination of total mercury in hair is described. The procedure chosen consists of the microwave digestion of 0.2-0.5g hair with 2 ml HNO3 and 1 ml H2O2 . The effect of washing and drying of the samples is investigated, and found not to influence analytical results when hair samples are collected after shampooing. However, freeze-drying of the samples results in the loss of 30% of mercury. The distribution of mercury along the length of a strand of hair is studied. It is shown to vary in adults (up to a factor of 7) but not in children (less than 20%). In the applications of this analytical method to population studies, the frequency of fish meals, and the age of the subject are positively correlated to the mercury levels in adults' hair (r = 0.539 and 0.513, respectively). Breast-feeding and mercury levels in children's hair are also correlated (r = 0.433). The relationship between number of fillings and mercury levels in adults' hair is not significant. No correlation was found between mercury levels in children's hair and Developmental Quotient (Griffith's scales) (r = -0.24 to 0.18).The optimisation of a coupled High Performance Liquid Chromatography - CV-AFS system for the study of mercury speciation is described. The use of KOH and microwave digestion for the extraction of mercury species was unsuccessful, and thus recommendations for future work are made.
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North, Teri-Louise. "Genetic epidemiological and population genetic studies of complex ageing traits." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.685359.
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The ageing process in humans is affected by lifestyle and by our genetics, the mechanisms of which we understand to varying degrees. Unpicking the phenotypic and genetic architecture of ageing traits will explain why there is such variability in the ageing phenotype. I begin with a study of physical and cognitive capability in middle to older aged individuals (Chapter 2). I use a SNP shown to associate with nicotine dependence in a Mendelian Randomization meta-analysis to explore the causality of the association of smoking with ageing, demonstrating how genetic information can be used to improve our understanding of the causal association of lifestyle and ageing traits. In Chapter 3, I meta-analyse the association of carrier status for four Mendelian diseases and physical capability, cognitive capability and lung function in ageing individuals to understand whether presumed asymptomatic heterozygotes present with a characteristic phenotype in later life. This study generated a novel finding: PI-MZ carrier status for alpha 1-antitrypsin deficiency is associated with increased height and increased respiratory capacity. In Chapter 4, I conduct the first metabochip-wide association scan of objective physical capability and self-reported disability in middle to older aged individuals, with the aim of identifying candidates for ageing genes. Lastly (Chapter 5), I conduct a simulation of evolution to test a pleiotropic model developed by Eyre-Walker (2010) regarding the genetic architecture of complex traits. I find good concordance between simulation and theory, although discrepancies arise due to the assumptions of the diffusion model. I discuss the potential portability of the pleiotropic model to the context of complex ageing traits. This thesis applies contrasting approaches to exploring phenotypic and genetic influences on complex ageing trais, enhancing our current understanding of how lifestyle and genetics shape our ageing phenome. In a world of increasing geriatric morbidity, such progress is of burgeoning importance.
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Whitt, Jeffrey Glen. "The Bobwhite Population Decline: Its History, Genetic Consequences, and Studies on Techniques for Locating and Assessing Current Populations." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1505132/.
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The northern bobwhite (Colinus virginianus) population decline is a severe, rangewide phenomenon beginning >150 years ago and continuing today. In this investigation, I: 1. document the timeline of bobwhite population decline and unintended genetic consequences of attempted remedies, 2) develop a model useful for predicting possible locations of potentially sustainable bobwhite populations in semiarid rangeland in Texas and Oklahoma, and 3) examine the relationship between population monitoring data and meteorological factors. While breeding season call counts of male bobwhite have been used for >70 years to provide estimates of fall populations for hunting, most studies of call counts have focused on mathematics and statistical accuracy of the count, largely overlooking the influence of meteorological factors on call counts. Here, I present the results of >4,400 individual point counts and examine their relationship with meteorological variables recorded at each stop. Humidity was positively correlated with the number of birds recorded (ρ = 0.275, p < 0.001) and temperature was negatively correlated (ρ = -0.252, p < 0.001). The number of birds recorded was significantly higher in wet years than in drought years. There was no significant correlation between wind velocity and number of birds recorded. These results suggest that, while weather does influence call counts and efforts should be made to record meteorological conditions when collecting call count data, the influence of weather may not easily factor into the analysis. These results also provide another line of evidence for decreased breeding behavior during high temperatures. With the increased focus on bobwhite habitat management on a regional scale, there is a need for reliable methods to identify potential bobwhite habitat. To identify bobwhite habitat in semiarid rangeland, I performed classification of LANDSAT scenes of Clay County, Texas from July and December 2015. Stands of mature little bluestem provide excellent bobwhite nesting cover and could be identified using LANDSAT imagery. I scored habitat by type, compared these scores with the results of breeding season call counts from 2014 and 2015 and found significant correlation. When used in combination with other landscape data, this approach can provide a regional context to inform conservation and management decisions.