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1
Beveridge, Maxine. « Molecular ecology of Dawson's burrowing bee Amegilla dawsoni (Hymenoptera : Anthophorini) ». University of Western Australia. School of Animal Biology, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0091.
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[Truncated abstract] In the last two decades, the use of microsatellites has revolutionized the study of ecology and evolution. Microsatellites, or short tandem repeats (STRs), are stretches of DNA repeats, 1 to 5 nucleotides long, where the number of repeats varies between individuals. They are co-dominant, highly variable, neutral markers, and are inherited in a Mendelian fashion. Microsatellite loci were isolated from Dawson’s burrowing bee, Amegilla dawsoni, a large, fast-flying solitary nesting bee endemic to the arid zone of Western Australia. Twelve polymorphic loci were found with an observed number of alleles ranging from two to 24 and observed heterozygosities between 0.17 and 0.85. These loci were used to examine two aspects of this bee’s molecular ecology; its population structure and mating system ... The molecular data were also used to show that the nesting female is the mother of all her offspring and that brood parasitism is unlikely in this species. The data indicate that females make daughters at the beginning of the season followed by large sons in the middle, and then small sons at the end. Females often place one brood cell directly above another. The distribution of sex and morph in these doublets follows a pattern with most containing a female on the bottom and a minor male on the top, followed by almost equal numbers of female on top of female and minor male on top of major male. This pattern is likely favoured by emergence patterns, with males emerging before females and minor males emerging before major males. I suggest that although minor males have low reproductive success, their production may nonetheless be beneficial in that minor males open up emergence tunnels for their larger and reproductively more valuable siblings. In addition, minor males may represent the ‘best of a bad job’ provisioning tactic arising from changes in the costs to nesting females of gathering brood provisions over the course of the flight season. This thesis demonstrates that microsatellites can be used to answer many questions regarding the molecular ecology of a species from the behaviour of the bees on a population scale to the mating behaviour of individual bees and how they allocate resources for the next generation. Many other aspects of the bee’s ecology could also be examined now that suitable molecular markers exist.
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Pelin, Adrian. « Population Genome-wide Analysis of Geographically Distant Isolates of the Bee Pathogen Nosema Ceranae ». Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32477.
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Microsporidia are a peculiar phylum of ancestral fungal relatives who have remained enigmatic and largely unknown up until the end of last century. Recent research has revealed some clues about their parasitic life style, and provided some answers regarding their basic biology. Research done as part of my Master’s degree has combined next generation genome sequencing and with powerful bioinformatics analyses to make new contributions in the field of microsporidian biology. In this dissertation, I will focus on describing the results of my main project, a population genomic study of an economically important microsporidium, Nosema ceranae. Infections from this species have been associated with recent global declines in the populations of western honeybees (Apis mellifera). Despite the outstanding economic and ecological threat that N. ceranae may represent for honeybees worldwide, many aspects of its biology, including its mode of reproduction, propagation and ploidy, are either very unclear or unknown. In my thesis, I aimed to expand our knowledge of N. ceranae biology by sequencing the genome of 8 isolates (i.e. a population of spores isolated from one single beehive) of this species harvested from 8 geographically distant beehives, and by investigating their level of polymorphism. Consistent with previous analysis performed using single gene sequences, my analyses exposed a very high genetic diversity within each isolate, but also very little hive-specific polymorphism. My investigations on the nature, location and distribution of this variation revealed that that beehives around the globe are infected by a population of N. ceranae cells that are polyploid (4n or more) and clonal. Furthermore, phylogenetic analyses I performed using genome-wide SNP data extracted from these parasites and mitochondrial sequences from their hosts all failed to support the current geographical structure of our isolates, suggesting that the isolates we analyzed have probably spread through human intervention. Altogether, research done as part of my Master’s degree has resulted in essential breakthroughs in our biological understanding of an economically and ecologically important parasite of honeybees.
3
Smith, Alan William. « Population dynamics and chemical ecology of the honey bee tracheal mite, Acarapis woodi (Acari : tarsonemidae), in Ohio / ». The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487677267729617.
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Dellicour, Simon. « Etude de l'histoire évolutive d'insectes phytophages : approche phylogéographique et développements méthodologiques ». Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209374.
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Yeni, Filiz. « Determination Of Polymorphism Of Pgm, Hk, Pgi, And G6pd In Different Developmental Stages Of Honey Bee (apis Mellifera L.) And Its Relation With Pgm Activity And Glycogen Content ». Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611930/index.pdf.
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In this study, three subspecies of Apis mellifera L. (A. m. caucasica, A. m. carnica, and A. m. syriaca) from different climatic regions were evaluated electrophoretically at ontogenetic level by means of four enzymes, namely Phosphoglucomutase (PGM), Hexokinase (HK), Phosphoglucose isomerase (PGI) and Glukose-6-phosphate dehydrogenase (G6PD). It is determined that only Pgm and Hk loci were polymorphic. Allele and genotype frequencies at Pgm locus changes seasonally whereas Hk locus does not exhibit seasonal variation. Within the scope of this study we investigated at which developmental stage shifting to heterozygotes prior to winter occurs.
It is found that there is a seasonal fluctuation throughout the year in Pgm genotype frequencies at each developmental stage studied and correlated with enzyme activity and glycogen content. As the studied enzymes have crucial
v
roles in insect energy metabolism, results of this study provided further information about the relationship between carbohydrate metabolism and enzyme polymorphism of honey bees.
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Radloff, S. E. (Sarah E. ). 1948. « Multivariate analysis of selected honeybee populations in Africa ». Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005420.
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Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus were analysed by multivariate methods to characterise selected honeybee populations along five transects in Africa at a meso-scale level of sampling distance resolution. In some, but not all, areas pheromonal clusters were found to be coincident and concordant with the morphometric clusters, thus indicating that different honeybee traits have dispersed variably among populations. All transects were found to contain areas of significantly high variance. High intracolonial variance was taken to indicate localised genetic variation coupled with out-cross matings. Centroids of high intercolonial variance occured at and between cluster boundaries and were typical of transitions between, and rainfall-temperature discontinuities within, ecological-climatological zones, hence areas of ecological instability. Principal component and stepwise discriminant analysis yielded three morphometric clusters corresponding to A. m. sahariensis and A. m. intermissa in Morocco and to A. m. iberica (with three biometric populations) in Spain, but no pheromone clusters. The combined morphometric and pheromonal variance spectra indicated regions of natural hybridisation along a Sahara-Pyrenees transect. In the Horn of Africa, discrete and statistically homogeneous populations were identified: A. m. jemenitica, A. m. bandasii, A. m. sudanensis in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance were interpreted as zones of hybridisation between the populations. Along a transect in west central Africa, three distinct homogeneous populations and two zones of hybridisation were found. These bees were designated as A. m. adansonii whose area of distribution was intruded by an un-named mountain group of bees and a third group, A. m. jemenitica. The delineation of the hybrid zones was supported by intercolonial variance spectra and these significant asymmetries were found to be coincident with transitions between the ecological-climatological zones. In southwestern Africa, two discrete homogeneous populations and a zone of hybridisation between them were identified: A. m. scutellata in northern South Africa and southern Namibia and A. m. adansonii in northern Namibia. Along a transect in the southeastern woodland savanna of Africa, three discrete populations were classified: A. m. litorea in Mozambique, A. m. scutellata in Zimbabwe and A. m. adansonii in northwestern Zambia. A zone of introgression between the last two subspecies occured in south-central Zambia and in the Zambezi valley.
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Delaney, Deborah A. « Genetic characterization of U.S. honey bee populations ». Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Summer2008/d_delaney_070108.pdf.
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Travassos, Guilherme Fonseca. « Two essays on consumer demand and population aging in Brazil ». Universidade Federal de Viçosa, 2018. http://www.locus.ufv.br/handle/123456789/19423.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Esta tese estuda dois tópicos sobre a demanda do consumidor e o envelhecimento populacional usando dados do Brasil. Mas, em primeiro lugar, apresentamos um capítulo introdutório sobre a situação dos idosos no Brasil abordando aspectos como a transição demográfica, o perfil dos idosos brasileiros, as condições sócias demográficas deste segmento e, finalmente, as consequências e as tendências do envelhecimento da população no Brasil. A intenção deste capítulo é introduzir os problemas de pesquisa relacionados à população idosa que serão apresentados nos próximos capítulos. No primeiro ensaio, analisamos o nível de bem-estar dos idosos. Compreender esse tema é importante para a formulação de políticas públicas e de transferência de renda para os idosos, como o cálculo das taxas de pobreza, do seguro de vida e das pensões por morte. No entanto, este tema é pouco conhecido nos países em desenvolvimento e estimativas de economias ricas podem ter uma validade externa limitada em comparação àqueles países. Assim, essa aplicação torna-se relevante no contexto brasileiro, uma vez que a grande maioria dos idosos sobrevive de programas de transferência de renda, tais como pensões pós morte e aposentadoria. Os resultados indicaram que as preferências dos idosos no Brasil são muito similares por gênero e ambos são mais sensíveis às mudanças nas despesas e nos preços dos bens relacionados à saúde. Os resultados indicaram substanciais economias de escala e a participação do idoso aumentando à medida que as despesas totais cresciam. A escala da OCDE subestima a pobreza entre idosas em casais e superestima a pobreza entre idosos homens em casais. No caso das viúvas e dos viúvos, na maioria dos períodos, a escala da OCDE subestima as taxas de pobreza. Finalmente, encontramos que a queda no bem-estar material após a morte da esposa é bastante substancial para os idosos homens e o oposto foi observado para as idosas. O segundo ensaio compara os padrões de gastos de consumo e a demanda, medida por elasticidades preços e dispêndio, dos domicílios em que o idoso ou o adulto não-idoso são os responsáveis, levando em consideração os fatores socioeconômicos associados ao comportamento do consumidor. Nosso estudo reconhece que as diferenças entre as despesas dos idosos e adultos são importantes para estabelecer políticas públicas adequadas para ajudar os consumidores idosos. No decurso do processo de envelhecimento, os agregados familiares idosos desempenharão um papel crescente, mas o seu comportamento pode diferir substancialmente das pessoas mais jovens. Novamente, pouco se sabe sobre essa questão nos países em desenvolvimento, especialmente na América Latina e principalmente no Brasil. Os resultados sugerem que os domicílios brasileiros chefiados por idosos e adultos não idosos têm diferentes padrões de consumo. Os domicílios chefiados por adultos são mais sensíveis às mudanças nas despesas com produtos alimentares, enquanto os domicílios chefiados pelos idosos apresentavam maior sensibilidade para os cuidados da saúde. Variáveis demográficas, principalmente gênero, nível educacional e transferências governamentais, influenciam a demanda pela maioria dos bens em famílias chefiadas por idosos no Brasil. As transferências governamentais ajudam as famílias idosas a gastar mais em Habitação, Alimentação e Saúde. Em relação às variáveis de composição domiciliar, os domicílios formados apenas pelos idosos demandam menos Alimentos e mais Habitação; os domicílios compostos por idosos com crianças demandam mais produtos relacionados a vestuário e transporte, e menos produtos de higiene e habitação; e os domicílios compostos por idosos com parentes exigem menos produtos de cuidados de saúde. Juntos, os dois ensaios contribuem para uma melhor compreensão sobre o padrão do consumo, a demanda dos consumidores e o bem-estar dos idosos usando dados do Brasil, uma economia em desenvolvimento.
This thesis studies two topics on consumer demand and population aging using Brazilian data. We first present an introductory chapter about the situation of the elderly in Brazil addressing aspects such as the demographic transition, the profile of the Brazilian elderly, the socio-demographic conditions of this segment and, finally, the consequences and trends of population aging in Brazil. The intention of this introductory chapter is to guide the research problems related to the elderly population that will be presented in the next chapters. In the first essay, we analyze the level of well-being of the elderly people. Understanding such theme is important for the design of public policies and income transfer for the elderly, such as the calculation of poverty rates, life insurance and death pensions. However, little is known about this topic in developing countries and estimates from rich economies may have limited external validity to the developing world. Thus, this application becomes relevant in the Brazilian context, since the vast majority of the elderly survive from income transfer programs, such as death pensions and retirement. Results indicate that elderly individual’s consumer preferences in Brazil are very similar by gender and both are more sensitive to changes in expenditure and price for Health care. The results indicate substantial economies of scale and a husband’s share that is increasing in total expenditures. OECD scale underestimates poverty among elderly women in couples and overestimates poverty among elderly men in couples. In the case of widow and widowers, in most of the periods, OECD scale underestimates poverty rates. Finally, we find that the drop in material well-being following the wife’s death is rather substantial for men and the opposite was observed for women. The second essay compares consumption expenditure patterns and demand, measure by price and income elasticities, of the elderly and adult-headed households, taking into account socio- economic factors associated to consumer behavior. Our study recognizes that differences between expenditure of the elderly and the adults are important in order to establish appropriate public policies to help elderly consumers. In the course of the aging process, elderly households will play an increasing role, but their behavior might differ substantially from younger people. Again, little is known about this issue in developing countries, especially those in Latin America, and mainly in Brazil. The findings suggest that Brazilian elderly and adult-headed households have different consumption patterns. Adult-headed households were more sensitive to changes in expenditure for Food products, while households headed by the elderly showed more sensitivity for Health care. Demographic variables, mainly gender, education level and government transfers, influence the demand for most of the goods in Brazilian elderly headed households. Government transfers help elderly households to spend more on Housing and Health care. In relation to household composition variables, those formed only by the elderly demand less Food and more Housing; those households composed by the elderly with children demand more Clothing and Transportation products and less Habitation and Health care products; and those households composed by the elderly with relatives demand less Health care products. Together, the two essays contribute to a better understanding about consumer pattern, consumer demand and well-being of elderly using data from Brazil, a developing economy.
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Wood, Thomas James. « The effect of agri-environment schemes on farmland bee populations ». Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/66427/.
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Over the past century there have been substantial declines in farmland biodiversity as a result of the intensification of agricultural practice. Concerns over these declines have led to the development of agri-environment schemes designed to mitigate the effects of intensive agriculture and to benefit biodiversity. Prior to commencing this thesis it was not clear if flower-rich, pollinator-focused agri-environment schemes had a population level impact on wild bees on farmland. Whilst previous work has shown that the creation of flower-rich habitat can provide suitable foraging resources for bumblebees, little was known about the impact of this management on bumblebee population sizes and even less on whether these resources were used by and benefited solitary bees. This thesis compares bee populations between farms with and without flower-rich, pollinator focused agri-environment schemes in Hampshire and West Sussex, UK. Using genetic techniques to estimate colony density, and hence population size, farms implementing targeted schemes had a significantly higher density of bumblebee nests for the four species studied (212 nests/km2 against 112 nests/km2). However, there was no difference in the species richness of bees between these different farm types. When assessing pollen use by solitary bees, flowering plants sown as part of pollinator-focused agri-environment schemes were not widely used, representing 27% of pollen foraging observations and 23% of pollen collected by volume. Only 35% of solitary bee species were found to use sown plants for pollen to a meaningful extent, with most pollen collected from plants persisting in the wider environment. The creation of flower-rich habitat significantly increased resource availability, but did not increase resource diversity. These results indicate that if diverse bee populations are to be maintained on farmland then agri-environment schemes must be developed that effectively increase the number of flowering plant species present at the farm scale.
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Melka, Hailu Dadi. « Genetic parameter estimates for weaning traits in a multibreed beef cattle population ». Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52285.
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Thesis (MScAgric)--University Stellenbosch, 2001.ENGLISH ABSTRACT: The aim of this study was to estimate genetic parameters as well as to evaluate the influence of some genetic factors on preweaning growth traits in a multi breed beef cattle population. These preweaning growth traits were birth weight (BW), weaning weight (WW) and average daily gain (ADG). Three aspects were addressed in this particular study; namely the Estimation of (co)variance components and genetic parameters, the effect of sire breeds and dam genotypes and the contribution of Charolais and Angus breeding levels on weaning traits in a multibreed beef cattle herd. Variance components and resulting genetic parameters of BW, WW and ADG in the population were estimated by Restricted Maximum Likelihood (REML) procedures. Four different unitrait and multitrait animal models were fitted ranging from a simple model with the animal direct effects as the only random effect to the model allowing for both genetic and permanent maternal environmental effects. The model that included directgenetic and permanent maternal environmental effects generally best described the data analysed. The simple model ignoring maternal effects most likely inflated direct heritability estimates. Direct heritability estimates were 0.11, 0.19, and 0.15 for BW, WW and ADG, respectively, fitting a multitrait model that comprised of both the genetic and maternal environmental effects. Under this comprehensive model, maternal heritabilties were low under both analyses, ranging from 0.02 to 0.10. Permanent maternal environmental effects were more important than maternal additive genetic effects for WW and ADG. Direct and maternal genetic correlations range from 0.42 to 0.44 for BW, -0.22 to -0.25 for WW and -0.17 to -0.23 for ADG, while the corresponding estimates ofunitrait analysis varied from 0.58 to 0.61 for BW, -0.43 to-0.53 for WW and -0.49 to -0.79 for ADG. The effect of Charolais and Hereford sires and dam breed genotypes on BW and WW in calves of Hereford, F I, two and three breed rotational as well as terminal crosses among the Charolais, Hereford, Angus and Bonsmara breeds were investigated. BW and WW of the Charolais sired calves were significantly (P
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Jabbarifarhoud, Houman. « Morphometric, Mtdna And Microsatellite Analysis In Honeybee Populations (apis Mellifera L.) Of North And Northwest Iran ». Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605463/index.pdf.
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ABSTRACT
MORPHOMETRIC, MtDNA AND MICROSATELLITE ANALYSIS IN HONEYBEE POPULATIONS (Apis mellifera L.) OF
NORTH AND NORTHWEST IRAN
Morphometric measurements, mitochondrial DNA analyses and 5 microsatellite loci were used to investigate variation in the honeybee populations of Iran and comparing it with the Turkish populations. Five honeybee populations were sampled from North and west north of Iran.
In morphometric aspect of the study 23 characters were measured from left forewings and hindlegs of honey bee samples. The data were analysed by multivariate statistical analyses.
By using mtDNA analyses length polymorphism of the intergenic region COI-COII of mitochondrial DNA was studied. After amplification of this region by the polymerase chain reaction, DraI enzyme was used for restriction of amplified region. Results of mtDNA studies show no diversity between four populations and all of them exhibit the same C1 pattern.
Five microsatellite loci (A7, A24, A28, A43 and A113) were used in this studies.A high level of average heterozygosity changing between 0.611 and 0.709 was detected in Iranian honey bee populations, and a significant degree of polymorphism was observed. Although Urmia, Sarein and Viladereg populations are similar, Amol population which has located in northern Iran shows a significant difference from other populations. Result obtained form morphometric studies are supporting microsatellite analyses. By comparing data obtained form Iranian honey bee populations with Turkish population (Hakkari), western populations (Urmia, Sarein and Viladereg) are more similar to Hakkari population. It is found Amol is significantly different form other populations and better represents Iranian honeybee.
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Koch, Jonathan Berenguer. « Biogeography, Population Genetics, and Community Structure of North American Bumble Bees ». DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4577.
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In 2011, several wild North American bumble bee pollinator species were reported to have declined by up to 96% in relative abundance in comparison to historic estimates, and one species was speculated to be extinct. None of these species have yet been documented to have recovered from these declines and additional species are now suggested to be at risk. Imperiled species in particular show increased specificity to narrow climatic envelopes, as opposed to putatively stable species. My dissertation describes patterns of population genetic diversity, structure, and gene flow pathways associated with climate variation and historical biogeography of bumble bees distributed in western North America. The results of my dissertation research suggests that (1) historic climate variability predicts contemporary patterns of population genetic structure and divergence in an economically important species, (2) color variability in bumble bees is likely associated with lineage diversification and phylogeography, (3) bumble bee community structure across evolutionary time is likely driven by Müllerian mimicry at narrow spatial scales, and (4) bumble bees inhabiting specialized ecological niches are associated with high levels of genetic fixation at regional spatial scales in the Pacific Northwest. The results of my research directly contribute to current efforts to effectively manage, conserve, and advocate for wild bumble bee pollinators in the context of global change.
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Pennington, David. « Studies of aspects of predation on the Manx scallop, Pecten maximus (L.) populations ». Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366391.
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Husman, Stephen H., Wililam B. McCloskey et Kyrene White. « Twin-Line Per Bed Plant Population and Variety Evaluation ». College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/197708.
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Two experiments were conducted at the University of Arizona Maricopa Agricultural Center in 2002 designed to evaluate cotton yield and fiber quality at various plant populations and to test cotton variety performance in a twinline per bed cotton production system. The plant population experiment consisted of four target populations which included 60, 80, 100, and 120,000 plants per acre (PPA) and two varieties, Stoneville 4892BR and AG3601. The resulting plant populations were 52800, 69200, 82800 and 96200 for ST4892BR and 54800, 70800, 90500 and 104500 for AG3601. The two lowest plant populations resulted in the highest lint yields for both varieties and were similar but there was a significant linear of decreasing yield with increasing plant population. The highest lint yields in the twin line variety experiment were DP449BR (1743 lb/acre) and DP5415R (1702 lb/acre) which were not statistically different.
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Karem, Joseph E. « Dynamics of Bee and Wasp Populations in Maine Lowbush Blueberry (Vaccinium angustifolium) ». Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/KaremJE2005.pdf.
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Cairns, Christine Elizabeth. « Effects of invasive Africanized honey bees (Apis Mellifera Scutellata) on native stingless bee populations (Meliponinae) and traditional Mayan beekeeping in Central Quintana Roo, Mexico ». FIU Digital Commons, 2002. http://digitalcommons.fiu.edu/etd/1970.
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The Maya of the Yucatan region have a long history of keeping the native stingless bees (subfamily Meliponinae). However, market forces in the last two decades have driven the Maya to favor the use of invasive Africanized honey bees (Apis mellifera scutellata) for producing large quantities of high quality honey which has an international market. Furthermore, the native bees traditionally used by the Maya are now disappearing, along with the practice of keeping them.
An interdisciplinary approach was taken in order to determine the social factors behind the decrease in stingless beekeeping and the ecological driving forces behind their disappearance from the wild. Social research methods included participant observation with stingless beekeepers, Apis beekeepers, and marketing intermediaries. Ecological research methods included point observations of commonly known melliferous and polliniferous plants along transects in three communities with different degrees of human induced ecosystem disturbance.
The stingless bee species most important to the Maya, Melipona beecheii, has become extremely rare, and this has caused a breakdown of stingless beekeeping tradition, compounded with the pressure of the market economy, which fuels Apis beekeeping and has lessened the influence of traditional practices. The community with the heaviest amount of human induced ecosystem disturbance also had the lowest degree of bee diversity, while the area with the most intact ecosystem had the highest diversity of stingless bees, though Apis mellifera was still the dominant species. Aggressive competitive behavior involving physical attacks by Apis mellifera against stingless bees was observed on several occasions, and this is a new observation previously unreported by science. Human induced disturbance of the ecosystem and competition with the Africanized honey bee are affecting the diversity and abundance of various bee species.
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Ledbetter, Trevor Anthony, et Trevor Anthony Ledbetter. « Anthropogenic Change, Effects on Bee Populations, and Consequences for a Sub-Alpine Plant Community ». Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/625032.
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Declines in pollinator populations due to anthropogenic influences have been well documented in recent years. However, the effects that these declines have had on floral visitors that utilize floral resources in exploitative manners have received little to no attention. Not all floral visitors are pollinators. Some rob nectar, which may impose fitness effects that range from negative to positive. Some plant-pollinator systems have seen dramatic declines not only in pollinators, but in nectar robbers, in recent years. What are the consequences to plants of these declines? I studied consequences of such a decline in Aquilegia caerulea, the Colorado Columbine.
During the 1970s, the floral visitor community and nectar robbing rate of A. caerulea were documented by Miller (1978). Bombus occidentalis, the Western Bumblebee, acted at that time as both the major floral visitor and an active nectar robber. In the subsequent 45 years, many studies have reported declines in B. occidentalis, earning it an IUCN Vulnerable Red List classification. Building from this information, I quantified fitness effects of nectar robbing as well as differences in the floral visitor community to A. caerulea compared to past studies. I determined the effects and consequences of these changes, particularly in relation to nectar robbing, on the floral community. I also quantified the presence and ability of flies (Diptera), whose abundance has recently been exceptionally high, to act as pollinators in the absence of effective pollinators (bumble bees).
I found that the floral visitor community has changed drastically since the studies of Miller (1978). Bombus occidentalis was nearly absent from the system in 2016, resulting in severely reduced nectar robbing rates. Nectar robbing was found to have no significant effect on fruit set, while Diptera floral visitors, which dominated the system in 2016, significantly reduced fruit set below the self-pollination rate for the flower in the absence of bumble bees. As a whole, the absence of a nectar robber for this system is insignificant as nectar robbing has no influence on the reproductive success of the plant, however, in the absence of all bumble bees, Diptera, now a primary floral visitor, does have a significant, negative influence on reproductive success.
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Liao, Renyuan. « Fermion Pairing and BEC-BCS Crossover in Novel Systems ». Kent State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883.
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Oliveira, Diego Moure. « Diversidade e estrutura genética de populações urbanas de abelhas Centridini (Hymenoptera : Apidae) visitantes florais de Tecoma stans (L) Kunth (Bignoniaceae) ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-03122013-114958/.
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Em abelhas, como nos demais himenópteros, a haplodiploidia e o mecanismo de determinação do sexo restringem o tamanho efetivo da população. Ademais, a nidificação próxima ao sítio natal pelas fêmeas das espécies solitárias restringe o fluxo gênico materno e causa alta viscosidade populacional. Centris é um gênero de abelhas solitárias da tribo Centridini, encontradas em distintos locais, como matas contínuas ou fragmentos florestais, bem como em ambientes urbanos; as espécies C. analis e C. tarsata se destacam no gênero pela abundância com que são encontradas nestas localidades. São abelhas poliléticas ou generalistas na coleta de pólen e nidificam em cavidades pré-existentes. Em razão de seu porte médio, presume-se que não apresentem alta capacidade de dispersão. Fêmeas de algumas espécies do gênero apresentam comportamento filopátrico. Estes dados nos levam a supor que espécies com traços biológicos similares tenham suas populações naturalmente estruturadas (subdivididas). Para testar esta hipótese, foram analisadas algumas regiões do genoma mitocondrial (DNAmt) de abelhas Centridini residentes em áreas urbanas. As duas subunidades da citocromo c oxidase (COI e COII), bem como o RNA transportador de leucina (RNAtLeu), apresentaram baixo nível de variação intra-específica, e a dificuldade em amplificar estas regiões para uma das espécies impediu a utilização destas regiões para análises populacionais. Desta forma, foram selecionadas duas regiões gênicas com taxas de variação intra-específicas distintas, o gene citocromo b (cytb) e a subunidade maior do DNA ribossômico (16S). Por ser uma molécula de herança materna, a análise destas regiões gênicas nos permitiu obter informações a respeito de colonização e o número de linhagens maternas. Os resultados deste trabalho sugerem que as populações de Centris tarsata e Centris trigonoides apresentam baixa e moderada estruturação, respectivamente. Para C. analis, a espécie mais bem amostrada, o excesso de picos duplos apresentados nos eletroferogramas dificultou a interpretação dos resultados. Foi possível ainda verificar diferenças na distribuição haplotípica de machos e fêmeas de C. tarsata, sugerindo a ocorrência de uma dispersão enviesada para machos, caracterizando uma dispersão sexo-assimétrica.In bees, as in other hymenopterans, the haplodiploidy and mechanism of sex determination constrain the effective population size. Moreover, the nesting close to home site by the females of solitary species restricts maternal gene flow and causes high population viscosity. Centris is a genus of solitary bees of the tribe Centridini found in different locations, such as continuous forests or forest fragments, as well as in urban environments; the species C. analis and C. tarsata stand out in the genre for the abundance that are found in these locations. They are polyletics bees, or generalists in collecting pollen, and nest in cavities pre-existing. In reason of its medium size, it is presumed that do not present high dispersal capacity. How some species of the genus are phylopatric, we presume that other also presenting similar behavior. These data lead us to suppose that species with similar traits have their populations naturally structured (subdivided). To test this hypothesis, we analyzed urban populations of four species of Centris for some regions of mitochondrial genome (mtDNA). The two subunits of cytochrome c oxidase (COI and COII) and the tRNA leucine (tRNALeu) showed a low level of intraspecific variation, and the difficulty to amplify those regions for one species prevented the use of these regions to population analysis. Thus, we selected two gene regions with distinct rates of intra-specific variation, the gene cytochrome b (cytb) and the large subunit ribosomal DNA (16S). As a molecule maternally inherited, the analysis of the mitochondrial genes enabled us to obtain informations about colonization through the number of maternal lineages. Our results suggest that Centris tarsata and Centris trigonoides populations exhibit low and moderate genetic structuring, respectively. In C. analis, the species most well sampled, the excess of double peaks showed in the electropherograms difficults the interpretation of results. Also, for the species C. tarsata was possible to verify differences between males and females, suggesting the occurrence of a male skewed dispersion and an asymmetrical dispersion.
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Liu, Huolong. « Modeling and control of batch pulsed top-spray fluidized bed granulation ». Thesis, De Montfort University, 2014. http://hdl.handle.net/2086/11006.
Texte intégralRésumé :
In this thesis, a thorough study of the batch top-spray fluidized bed granulation was carried out including experimental study, population balance model (PBM), computational fluid dynamic (CFD) study and control strategy development. For the experimental study, the influence variables of pulsed frequency, binder spray rate and atomization pressure of a batch top-spray fluidized bed granulation process were studied using the Box-Behnken experimental design method. Different mathematical models were developed to predict the mean size of granules, yield, relative width of granule distribution, Hausner ratio and final granule moisture content. Validation experiments have shown the reliability and effectiveness of using the Box-Behnken experimental design method to study a fluidized bed granulation process. The one-dimensional population balance models (ODPBMs) have been developed to model a pulsed top-spray fluidized bed granulation, linking the operating factors of the pulsed frequency, the binder spray rate, and atomization air pressure with the granule properties to predict granule growth behavior at different operating conditions. A multi-stage open optimal control strategy based on the developed ODPBMs was proposed to reduce the model and process mismatch through adjusting the trajectory of the evolution of the granule size distribution at predefined sample intervals. The effectiveness of the proposed modeling and multi-stage open optimal control strategy has been validated by experimental and simulation tests. In addition, an Eulerian-Eulerian two-fluid model (EETFM) was developed to describe the gas-particle two-phase flow in the fluidized bed granulator. By computational fluid dynamic analysis, it has been proven that the fluidized bed granulation system is not homogeneous, based on which a two-compartmental population balance model (TCPBM) was developed to describe the particle growth in the fluidized bed granulation. Validation experiments have shown the effectiveness and superior accuracy of the TCPBM comparing with the ODPBM in predicting the final particle size distribution.
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Nadarajah, Kanagasabai. « Evaluation of phenotypic and genetic trends in weaning weight in Angus and Hereford populations in Virginia ». Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/74717.
Texte intégralRésumé :
Total weaning weight records of 29,832 Angus and 15,765 Hereford calves born during 1953 through 1983 in Virginia were used to evaluate phenotypic and genetic trends for adjusted weaning weight (AWWT), weaning weight ratio (WWR) and deviation of AWWT from the mean AWWT of the contemporaries (DEVN). Two approaches, namely the regression techniques and maximum likelihood (ML) procedure were taken to estimate the above trends.
The estimates of annual phenotypic trend for AWWT in the Angus and Hereford breeds were .96 and .82 kg/yr, respectively. The sire and dam genetic trends obtained from both approaches for the traits of interest were positive and significant; however, the estimates from the regression analyses were slightly higher than those- from the ML procedure. The estimates of one-half of the sire genetic trends obtained from ML procedure for WWR and DEVN were .40 ± .04 ratio units/yr and .72 ± .07 kg/yr in the Angus breed and the corresponding values for the Hereford breed were .25 ± .06 ratio units/yr and .45 ± .12 kg/yr. The estimates of one-half of the darn trends for the corresponding traits were .32 ± .02 ratio units/yr and .55 ± .04 kg/yr for Angus and .21 ± .03 ratio units/yr and .30 ± .07 kg/yr for Herefords. The application of adjustment factors (to eliminate the bias due to non-random mating and culling levels) to estimates of sire genetic trends in the regression analyses produced estimates more similar to the estimates obtained from the ML procedure. The average annual genetic trends over the study period from the ML procedure for AWWT were 1.27 kg/yr for Angus and .75 kg/yr for Herefords.Ph. D.
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Ben, Bahria-Sediki Islem. « Recherche de biomarqueurs pronostiques dans le cancer de la vessie dans la population Tunisienne ». Thesis, Paris, EPHE, 2016. http://www.theses.fr/2016EPHE3032/document.
Texte intégralRésumé :
Le cancer de la vessie représente un vrai problème de santé publique, avec une surveillance et suivi clinique à long terme en raison de l’importance des fréquences de récidives. La chimiothérapie reste souvent inefficace. L’objectif de cette thèse est donc la recherche de marqueurs sérologiques et moléculaires à valeur pronostique dans le cancer de la vessie qui peuvent servir à prédire la maladie. D’abord, nous avons étudié trois facteurs de transcriptions des lymphocytes T activées qui sont T-bet, GATA-3 et Bcl-6. Nous avons montré une surexpression de T-bet chez les malades à stade invasif et de haut grade, cependant, la surexpression de GATA-3 et Bcl-6 a été corrélée au stade superficiel et de bas grade. La survie a été corrélée avec le groupe des malades sans histoires de récidive ou progression et avec la surexpression de Bcl-6 et GATA-3. Cependant les malades qui expriment fortement T-bet répondent mieux au BCG. Ensuite, nous avons visé la détection de FasL et TRAIL solubles dans le sérum des malades atteints du cancer vésicale. Nous avons montré une surexpression de sFasL et sTRAIL chez les malades à stade superficiel et de bas grade. Le rôle anti-tumoral de ces cytokines a été confirmé sur deux lignées du cancer de la vessie montrant que le traitement avec le sérum riche en sFasL ou en sTRAIL diminue la viabilité cellulaire in vitro. A la fin de cette thèse, nous avons testé l’activation p-Akt dans la tumeur vésicale. Nous avons montré une surexpression de p-Akt au sein des tumeurs comparées au tissu sain adjacent, et au sein des malades à stade invasif et de haut grade. Akt semble être un marqueur de progression tumorale dans le cancer de la vessieBladder cancer is the first most common urogenital cancer in men in Tunisia, with a high recurrence rate. Patients with muscle-invasive disease develop metastasis. The need for expensive continuous surveillance. In this thesis we try to search some candidate biomarkers. Their use for cancer staging and personalization of therapy at the time of diagnosis in order to identify a better treatment could improve patient care. The aim of this first part of our study was to investigate the clinical significance of three immune cell-related transcription factors, T-bet, GATA-3 and Bcl-6 in Tunisian patients with bladder cancer. We found that T-bet level was significantly higher in invasive carcinoma with high- grade. However, T-bet is predictive of response to BCG. On the contrary, the expression of GATA-3 and Bcl-6 was significantly higher in non-invasive carcinoma with low grade. We furthermore studied the effect of activation of soluble FasL and TRAIL molecule in bladder cancer. We demonstrate that the mean serum level of sFasL was higher in patients than in normal donors. sFasL was only higher than in sera of healthy donors where patients had superficial stage and low- and medium-grade cancer. sTRAIL was significantly lower in sera from patients with invasive and high-grade bladder carcinoma than in controls. Finally, we demonstrate that p-Akt levels in patients with invasive carcinoma and high-grade bladder cancer were significantly elevated compared to patients with non-invasive and low grade bladder cancer. Altogether, our results suggest that Akt activation can provide useful prognostic information
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Alhamlan, Fatimah S. « Evidence for genetic differences in the Africanized honey bee populations of South and North America ». Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Summer2007/f_alhamlan_052207.pdf.
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Scriven, Jessica J. « The ecology and population genetics of a complex of cryptic bumblebee species ». Thesis, University of Stirling, 2016. http://hdl.handle.net/1893/24771.
Texte intégralRésumé :
Bumblebees are ecologically and economically important as pollinators, but some species are suffering severe declines and range contractions. In this thesis, three cryptic bumblebee species are studied to elucidate differences in their distribution, ecology and population genetics. As a result of their high morphological similarity, very little is known about the lucorum complex species: B. lucorum, B, cryptarum and B. magnus. In this study, their distributions across Great Britain were assessed using molecular methods, revealing that B. lucorum was the most abundant and most generalist of the three species, whereas B. magnus was the rarest and most specialised, occurring almost exclusively on heathland. Additionally, both B. magnus and B. cryptarum were more likely to be present at sites with cooler summer temperatures. Cryptic species represent interesting models to investigate the levels of niche differentiation required to avoid competitive exclusion. Characterising the niches of these species at a single site across the flight season revealed differences along three niche dimensions: temporal activity, weather sensitivity and forage-resource use. These species exhibited asymmetric niche overlap; a combination of ecological divergence and spatio-temporal heterogeneity may contribute to maintaining them in sympatry. Population genetic studies can be highly informative for understanding species ecology and for conservation management. The differences in habitat specialisation exhibited by these bumblebee species provide the opportunity to test conflicting hypotheses about links between dispersal and ecological specialisation: are habitat specialists selected to have low or high dispersal ability? Based on microsatellite analysis, the generalist B. lucorum had high levels of genetic diversity and little population structure across large spatial scales. The habitat specialist B. magnus had the lowest genetic diversity but similar levels of population differentiation to the moderate generalist, B. cryptarum. However, unlike B. cryptarum, B. magnus population differentiation was not affected by geographic distance, suggesting that this specialist species may maintain effective dispersal across large scales despite being restricted to a fragmented habitat. Bergmann’s rule is a well-known ecogeographic rule describing geographical patterns of body size variation, whereby larger endothermic species are found more commonly at higher latitudes. Ectotherms, including insects, have been suggested to follow converse Bergmann’s gradients, but the facultatively endothermic nature of bumblebees makes it unclear which pattern they should adhere to. This thesis reports caste-specific differences in body size between the three lucorum complex species in agreement with Bergmann’s rule: queens and males of B. cryptarum and B. magnus, which were found more commonly at higher latitudes and at sites with cooler temperatures, were larger than those of B. lucorum. Population genetic studies of invertebrates generally require the destruction of large numbers of individuals, which is often undesirable. Testing a variety of faecal collection and DNA extraction methods demonstrated that it is possible to obtain DNA of sufficient quality for genotyping from bumblebee faeces, without harming the individuals. This method would be valuable for studies of rare or declining bee species, for queens in reintroduction projects, and may be applicable to other arthropods. Overall this thesis contributes substantially to our knowledge of the ecology and population genetics of three important pollinator species. It provides data to inform species conservation, as well as understanding of ecosystem functioning and population dynamics. Furthermore, it successfully uses these cryptic species as a model to test several fundamental ecological theories.
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Cureton, Andrew N. « Gene flow within and between sea beet (Beta vulgaris ssp.maritima) populations ». Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403467.
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Stelzer, Claus-Peter. « Ressourcenlimitation bei Individuen und Populationen planktische Rotatorien als Modellorganismen / ». [S.l. : s.n.], 1999. http://e-diss.uni-kiel.de/diss,/d321.pdf.
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Acuff, Jennifer Claire. « Evaluation of individual and combined antimicrobial spray treatments on chilled beef subprimal cuts to reduce Shiga toxin-producing Escherichia coli populations ». Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35504.
Texte intégralRésumé :
Master of ScienceFood Science Institute
Randall K. Phebus
Due to the potential of Shiga toxin-producing Escherichia coli (STEC) contamination, beef processors use various antimicrobial interventions throughout the slaughter and fabrication processes to reduce risks of contaminating the food supply. Certain antimicrobials are approved and marketed for spraying onto chilled subprimal cuts; however, administering these treatments through commercial-scale equipment against foodborne pathogens is not fully validated. This study evaluated the efficacy of three common antimicrobial sprays, individually (Study 1) and combined (Study 2), against a rifampicin-resistant STEC cocktail (O26, O45, O103, O111, O121, O145, and O157:H7) using a commercial style subprimal spray cabinet. For Study 1, beef subprimals (n=16) were mist-inoculated with the cocktail (ca. 5 log CFU/cm²), followed by spray-treatment with individual antimicrobials [200 ppm peracetic acid (PAA), 2% Centron™ (sulfuric acid, sodium sulfate anhydrous and water mixture; CEN), 4.5% lactic acid (LA), or water (W)]. Study 1 was designed as randomized generalized block. After each treatment phase, STEC population reductions were quantified. As individual antimicrobial treatments, LA and PAA provided greater (P ≤ 0.05) STEC reductions (0.5 and 0.6 ± 0.08 log CFU/cm², respectively) compared to water (0.2 ± 0.08 log CFU/cm²), but the CEN reduction (0.4 ± 0.10 log CFU/cm²) was statistically similar to W. To test the efficacy of combined treatments on subprimal cuts in Study 2, a split-plot design was used using three replications. The inoculated subprimals (n=4) were first treated with PAA, LA, CEN, or W; vacuum packaged; and stored for 72 hours at 4°C. Each subprimal was then divided (n=16) and treated with each of the four antimicrobials as a second treatment. Cumulative reductions from the two treatments and storage ranged from 0.5 to 1.5 log CFU/cm² (± 0.3 log CFU/cm²); the greatest reduction was observed when subprimals were treated with LA followed by vacuum packaged storage and another LA application. Nevertheless, there was no statistical significance among treatments for a particular combination of treatments in Study 2. These studies indicate that the individual antimicrobial treatments evaluated are marginally effective for reducing STEC populations on chilled beef subprimal cuts during fabrication. Although there does not seem to be a specific combination of treatment that is more effective than another, the overall bacterial reduction may be improved by combining treatments when the beef is stored under vacuum packaged conditions and retreated upon bag opening, as typical of mechanical tenderization operations.
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Barrera, Carvajal Alejandro [UNESP]. « Estrutura populacional e estimação de parâmetros genéticos para características associadas ao desempenho reprodutivo em bovinos da raça Caracu ». Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151868.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O conhecimento da estrutura de uma população é importante quando se deseja manter a variabilidade genética em programas de melhoramento genético. As estimativas dos parâmetros genéticos permitem identificar as características de interesse econômico que podem responder a seleção direta ou indireta. Neste trabalho, objetivou-se avaliar a estrutura genética populacional e estimar os parâmetros genéticos para as características peso corporal da fêmea na entrada (PEP) e na saída (PSP) da primeira estação de monta, idade ao primeiro parto (IPP), peso corporal da vaca ao primeiro parto (PPP), peso corporal da vaca ao primeiro desmame (PPD) e perímetro escrotal aos 378 dias (PE378) em bovinos da raça Caracu, para avaliar critérios de seleção e os procedimentos de acasalamento para manter a variabilidade genética da população. A estrutura genética da população foi avaliada pelo tamanho efetivo (Ne), número efetivo de fundadores (fe), número efetivo de ancestrais (fa), intervalos de geração, coeficiente de endogamia (F), coeficiente de parentesco médio (AR) e integridade do pedigree. Os parâmetros genéticos foram estimados pelo método de máxima verossimilhança restrita (REML) por meio de modelo animal multi-característica. Os resultados obtidos para Ne na geração máxima, completa e equivalente, foram 180,90; 57,39; e 92,38, respectivamente. O valor para fe foi de 199 e para fa de 27. O coeficiente de endogamia médio e o parentesco médio foram 2,14% e 5,72%, respectivamente. Na avaliação da integridade do pedigree foram identificados 94,83% das mães e 93,82% dos pais com registros de origem. As estimativas de herdabilidade para as características de peso corporal variaram de 0,37 ± 0,09 (PPP) a 0,46 ± 0,08 (PPD). Para as características reprodutivas, as estimativas de herdabilidade foram 0,31 ± 0,10 para PE378 e 0,10 ± 0,06 para IPP. As correlações genéticas variaram de -0,37 ± 0,30 (PE378 e IPP) a 0,94 ± 0,06 (PSP e PPP). As correlações genéticas entre os pesos corporais medidos durante o primeiro ciclo reprodutivo e IPP indicaram que a seleção visando controlar o peso corporal nesse período não irá afetar a idade ao primeiro parto. A correlação genética favorável obtida entre PE378 e IPP (-0,37±0,30) indicou que a seleção para PE378 nos machos poderá favorecer a redução de idade ao primeiro parto das fêmeas. A partir dos parâmetros populacionais, concluiu-se que a variabilidade genética da população tem sido mantida, assim como os níveis de endogâmia, em decorrência do controle dos acasalamentos no decorrer das gerações.
The knowledge of the structure of the population is important to desired to maintain genetic variability in breeding programs. The genetic parameters estimates allow identifying economic interest traits that can respond to direct or indirect selection. The goal of this study was to evaluate the population genetic structure and to estimate the genetic parameters for the body weight of the cow at the beginning (WBF) and at the end (WEF) of the first breeding season, age at first calving (AFC), body weight of cow at first calving (WFC), body weight of cow at first weaning (WFW) and scrotal circumference measured at 378 days (SC378) in Caracu beef cattle, to assess the selection criteria and to indicate mating procedures to maintain the genetic diversity of the population. The genetic structure of the population was verified of the effective population size (Ne), the effective number of the founders (fe), the effective number of the ancestors (fa), the generational intervals, the inbreeding coefficient (F), the average relatedness (AR) and of the pedigree integrity. The restricted maximum likelihood method (REML) was used to estimate the genetic parameters under multitrait animal model. The maximum, complete and equivalent generation for Ne was 180.90; 57.39 and 92.38, respectively. For the fe were 199 and for fa 27. The average of the inbreeding coefficient and the AR were 2.14% and 5.72%, respectively. The integrity of the pedigree identified was 94.83% of the dam and 93.82% of the sire with known initial records Estimates of heritability for body weight traits ranged from 0.37 ± 0.09 (WFC) to 0.46 ± 0.08 (WFW). For the reproductive traits, the heritability estimates were 0.31 ± 0.10 for SC378 and 0.10 ± 0.06 for AFC. Genetic correlations ranged from -0.37 ± 0.30 (SC378 and AFC) to 0.94 ± 0.06 (WEF and WFC). Genetic correlations between body weights measured during the first reproductive cycle and the AFC indicated that selection to control body weight in this period will not affect age at first calving. The favorable genetic correlation obtained between SC378 and AFC (-0.37 ± 0.30) indicated that selection for SC378 of males may reduce the age at first calving of females. The population parameters showed that the genetic variability of the population has been maintained, as well as the levels of the inbreeding due to the control of mating during the generations.
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Abin, Samuel Atanasio Mustafa. « Animal recording as a tool for improved genetic management in African beef cattle breeds ». Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/46030.
Texte intégralRésumé :
Population structure in five African beef cattle breeds in South Africa was investigated, to assess the effect of animal recording in management of genetic diversity and genetic improvement. Pedigree records of 247,173 Afrikaner, 57,561 Boran, 198,557 Drakensberger, 256,692 Nguni and 55,309 Tuli breed were analysed using the online POPREP software system. Pedigree completeness over six generations varied with the lowest completeness in the Boran and the highest in the Afrikaner.The average generation interval ranged between 6.0 to 6.4 years. The rates of inbreeding per year were 0.03%, 0.04%, 0.06%, 0.07% and 0.08% in Boran, Nguni, Afrikaner, Drakensberger and Tuli respectively. Effective population sizes were 89, 107, 122, 191 and 364 in Tuli, Afrikaner, Drakensberger, Nguni and Boran respectively. Inbreeding and effective population size for the Boran was not a true reflection due to poor pedigree recording. These results indicate that none of the breeds are in critical limits of endangerment. Breeding values were regressed on birth year of each breed for weight traits; Kleiber ratio and scrotal circumference from 1986 to 2012. Genetic trends were stable for birth weights except the Afrikaner and Tuli. Genetic progress has been made in weaning and post weaning weights for all the breeds except for limited progress in the Nguni. Kleiber ratio and scrotal circumference in all measured breeds have shown good progress. The results of this study confirmed that recording of pedigree and performance records are effective in maintenance of genetic diversity and genetic improvement through selection based on EBVs of recorded traits.Dissertation (MScAgric)--University of Pretoria, 2014.
tm2015
Animal and Wildlife Sciences
MScAgric
Unrestricted
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Bizotto, Lucas de Almeida. « Avaliação populacional, sanitária e recursos armazenados em colmeias de Apis mellifera Linnaeus, 1758 (Hymenoptera : Apidae) utilizadas em serviços de polinização em pomares de macieiras (Malus domestica Borkh.) ». Universidade do Estado de Santa Catarina, 2016. http://tede.udesc.br/handle/handle/2385.
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Capes
This study aimed to evaluate the behavior and health of hives of honeybees (Apis mellifera) used in pollination services in apple orchards in the municipality of Vacaria, RS. Conducted under the conventional production system. For that were evaluated during two consecutive seasons (2014/15 and 2015/16), the behavior of bees in the collection of flowers resources during the pollination period (09/23/14 to 10/20/14 – crop season 2014 / 15, 09.02.15 and 15.10.15 and between 2015/16 crop season), the occurrence of parasitism by Varroa destructor mites and infections caused by Nosema sp. areas of stored features, and areas of immature hives and A. mellifera used in the pollination of apple orchards. In the course of experiments, the hives had activities during evaluations with an average of 27.5 to 40.8’ bees observed in five minutes. Regardless of the place of origin of the hives or evaluation harvest, the nectar was the preferred feature by bees. It was found that 95% of the bees have sought nectar while only 5% of the search effected pollen. In both crops, beehives used had average ranging from 3.0 to 6.7% of parasitism by V. destructor. There was an increase in parasitism levels in the period of pollination, in high population hives, since hives with smaller populations have not followed the same behavior. The presence of spores Nosema sp. It was noted only in hives used in the harvest of 2014/15, and did not occur in the harvest of 2015/16. There are significant variations in the internal areas of stored resources and areas of immature of hives used for pollination of apple trees services, these related to places of origin, before the entry of the swarms in the orchards. It is that coming from places with large supply of resources are the most affected by the stay in the orchard. which they suffered decreases in the internal space of the hives by the withdrawal of nests in preparation for the stay in the orchards. This fact led to numerous swarming bees reflecting in food reserves and population status.
O presente estudo objetivou avaliar o comportamento e a sanidade de colmeias da abelha melífera (Apis mellifera) utilizadas em serviços de polinização em pomares de macieiras no município de Vacaria, RS. Conduzidos sob o sistema convencional de produção. Foram avaliados, no decorrer de duas safras consecutivas (2014/15 e 2015/16), o comportamento das abelhas na coleta de recursos florais no decorrer do período de polinização (23/09/14 a 20/10/14 - safra 2014/15, e entre 02/09/15 e 15/10/15 - safra 2015/16), a ocorrência de parasitismo pelo ácaro Varoa destructor e infecções causadas por Nosema sp., áreas de recursos armazenados, e áreas de imaturos em colmeias e de A. mellifera utilizadas na polinização de pomares macieiras. No decorrer do presente experimento as colmeias apresentavam atividades durante as avaliações com média de 27.5 a 40.8 abelhas observadas em cinco minutos. Independentemente do local de origem das colmeias ou safra de avaliação, o néctar foi o recurso preferido pelas abelhas. Foi verificado que 95% das abelhas buscaram o néctar enquanto apenas 5% efetuaram a busca de pólen. Em ambas as safras, as colmeias utilizadas apresentaram médias que variam de 8 3,0 a 6,7 % de parasitismo por V. destructor. Houve aumento nos níveis de parasitismo no período da polinização, em colmeias com alta população, já colmeias com populações menores não seguiram o mesmo comportamento. A presença de esporos de Nosema sp. foi constata apenas em colmeias utilizadas na safra de 2014/15, e não ocorreu na safra de 2015/16. Há variações significativas nas áreas internas de recursos armazenados e áreas de imaturos das colmeias utilizadas em serviços de polinização de macieiras, estas ligadas aos locais de origem, antes da entrada dos enxames nos pomares. Sendo que os vindos de locais com grande oferta de recursos são os mais prejudicados pela estada no pomar, os quais sofreram pelas diminuições no espaço internos das colmeias pela retirada de sobre ninhos em preparação para a estadia nos pomares. Fato que levou a inúmeras enxameações, refletindo nas reservas de alimentos e estado populacional
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田代, 喬., Takashi TASHIRO, 真介 加賀, Shinsuke KAGA, 哲郎 辻本 et Tetsuro TSUJIMOTO. « 個体群動態モデルの生息場評価手法への導入に関する基礎的研究 ». 土木学会, 2003. http://hdl.handle.net/2237/8578.
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Mahari, Saâdia. « Etude synécologique des niveaux de peuplement arthropodien de l'écosystème chêne-liège dans les suberaies de la Mamora et de Ben Slimane (Maroc) ». Aix-Marseille 3, 1992. http://www.theses.fr/1992AIX3A004.
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Carden, Kerilynn M. « Macrophytes as fish habitat : the role of macrophyte morphology and bed complexity in fish species distributions / ». Link to abstract, 2002. http://epapers.uwsp.edu/abstracts/2002/Carden.pdf.
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Fernandez, Moguel Leticia. « Modélisation par CFD de la précipation du carbonate de baryum en réacteur à lit fluidisé ». Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL074N/document.
Texte intégralRésumé :
La mécanique des fluides numérique (CFD) est utilisée pour modéliser la précipitation du carbonate de baryum dans un réacteur à lit fluidisé. L’étude est divisée en deux parties : la modélisation de l’hydrodynamique du réacteur et la modélisation de la précipitation du carbonate de baryum. Pour ces deux parties, les modèles sont validés par l’expérience. Dans la première partie de l’étude, des réactions instantanées de neutralisation en absence et en présence de particules solides inertes sont mises en œuvre dans le réacteur à lit fluidisé. Pour représenter la réaction chimique dans la phase liquide, plusieurs modèles son testés : le modèle Eddy Dissipation (EDM), le modèle Eddy Dissipation Concept (EDC) et le modèle modifié Eddy Dissipation- Multiple Time Scale turbulent mixer (EDM-MTS). Le modèle qui donne la meilleure prédiction de la réaction chimique est choisi : il s’agit du modèle EDM-MTS, qui demande aussi le moins de temps de calcul. Dans la deuxième partie, l’équation de bilan de population est incorporée au code de calcul pour prédire la distribution de taille des particules (PSD). La méthode des classes est implémentée couplée avec le modèle des écoulements multiphasiques Eulérien-Eulérien, le modèle de turbulence k-e et le modèle EDM-MTS. Les cinétiques de précipitation de BaCO3 sont incluses dans le modèle. Des expériences de précipitation du BaCO3 en réacteur à lit fluidisé permettent de valider le modèle de CFD développé. La PSD donnée par le modèle de CFD est en bonne concordance avec les résultats expérimentauxComputational Fluid Dynamics (CFD) techniques are used to model the precipitation of Barium Carbonate in a solid-liquid fluidized bed reactor. The study is divided in two sections: The hydrodynamic behavior and the barium carbonate precipitation. The CFD model is validated with experimental results for both cases. In the first part, a neutralization reaction in the fluidized bed column with and without solids is carried out. In order to simulate the liquid phase reaction, the Eddy Dissipation Model (EDM), the Eddy Dissipation - Multiple Time Scale turbulent mixer model (EDM-MTS) and the Eddy Dissipation Concept (EDC) reaction models are tested. The model EDM-MTS is chosen for giving the best approach and for being the less computationally expensive. In the second part, the population balance equation is added to the model in order to calculate the Particle Size Distribution (PSD) in the fluidized bed reactor. The discrete method is chosen to solve the population balance equation coupled with the multi-phase Eulerian-Eulerian model, the k-e turbulence model and the EDM-MST model. The nucleation, growth and aggregation kinetics of BaCO3 are included in the precipitation model. The experimental BaCO3 precipitations realized in a fluidized bed reactor allowed the CFD precipitation model validation. The PSD obtained by CFD are in good agreement with the experimental PSD
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Gonzalez, John Michael. « Effect of ractopamine-hydrochloride on muscle fiber morphometrics, satellite cell population, and shelf-life properties of beef cattle ». [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0022824.
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Vimont, Michael. « The anthropological construction of Czech identity : academic and popular discourses of identity in 20th century Bohemia ». Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:bb316968-60a1-472c-bee4-b8de3af5ebbd.
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Through close textual analysis of 20th century Czech anthropological texts from the Revivalist and Socialist periods and contemporary social research conducted after the Velvet Revolution, I demonstrate certain prominent discourses of identity developed in early Bohemian anthropology and their continuities in present day popular discourses. In each period, identity is deeply intertwined with teleological theories of history with Czech populations at the apex of cultural evolutionary development. In the Revivalist period this apex was believed to be the democratic nation state, transitioning to a Marxist nation state in the Socialist period, and in the contemporary period is conceived of as a neoliberal nation state. A major function of anthropology in the Revivalist and Socialist periods was to legitimate either period’s respective teleological theory and Czech possession of relevant values as 'objective' and 'natural' fact, a general mode of discourse which continued in the contemporary period in numerous editorials in the 1990s on the advantages of capitalism. The contemporary manifestation has particularly noteworthy consequences for the Roma minority, which I argue has provided Czech discourses with an ethnic category 'anti-thetical' to their own identity, providing a 'repository' for negative Czech self-stereotypes emerging from collaboration in the Socialist period.
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田代, 喬., Takashi TASHIRO, 慎多郎 渡邉, Shintaro WATANABE, 哲郎 辻本 et Tetsuro TSUJIMOTO. « 低攪乱な礫床河川に優占する造網型トビケラの固体群動態とそれに伴う河床固化に関する解析 ». 土木学会, 2005. http://hdl.handle.net/2237/8594.
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Fuller, Robert A. « The interactions of toluic acid with indigenous microbial populations in a model Gravel Bed Hydroponic system ». Thesis, University of Portsmouth, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310419.
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Aldosari, Saleh 1964. « Measurement of and selection for insecticide resistance in various populations of beet armyworm Spodoptera Exigua (Hubner) ». Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/278716.
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A comparative study was performed to investigate the tolerance levels of beet armyworm to three insecticides, cyfluthrin, profenofos, and methomyl. The field strains were collected from Yuma and Marana, AZ whereas the susceptible laboratory strain was obtained from California. Dosage-mortality data were obtained by topical application on third instar larvae. Compared to the susceptible strain, both Yuma and Marana strains exhibited an increase in the LD50 to cyfluthrin by 15.65 and 5.45-fold, respectively. Both strains also exhibited an increase in the LD50 to profenofos and methomyl by 14.10, 17.77 and 2.95, 8.07-fold, respectively. The cyfluthrin-selected strain (Marana strain) tested for cross resistance to profenofos and methomyl and exhibited an increase in LD50 by 24.68 and 3.32-fold,respectively.
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Gössler, Birte [Verfasser]. « Häufigkeit und klinischer Verlauf von HPV-Infektionen bei Kopf-Hals-Tumoren in einer Population in Nordrhein-Westfalen / Birte Gössler ». Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1125658150/34.
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Ivgin, Tunca Rahsan. « Determination And Comparison Of Genetic Variation In Honey Bee (apis Mellifera L.)populations Of Turkey By Random Amplified Polymorphic Dna And Microsatellite Analyses ». Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610443/index.pdf.
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We analyzed a total of 760 worker bees, two samples per colony, 390 colonies in 26
provinces in Turkey to determine and compare the genetic variation of Turkish
honey bee (Apis mellifera L.) populations using 10 primers for RAPD and 6
microsatellite loci. Mean gene diversity levels ranged from 0.035 (Sanliurfa) to 0.175
(Antalya) for RAPD and 0.449 (Mugla) to 0.739 (Artvin) for microsatellite markers.
Private band patterns and alleles, pairwise FST values support that the Anatolian
honey bees belong to C lineage except for Hatay and Sanliurfa populations illustrated
from previous findings of mitochondrial DNA studies. Genetic differentiation (GST)
from RAPD data ranged from 0.060 (Bilecik and Mugla) to 0.395 (Gökç
eada and Sanliurfa). The genetic diversity (FST) for microsatellites ranged from -0.068 (Gö
kç
eada and &
#272
zmir) to 0.347 (Konya and Mugla). The results of the present research are in agreement to that of previous study in Turkish honey bee populations which used different microsatellite loci. That is the genetic variation was the highest in African, the lowest in European and intermediate in the Mediterranean honey bee populations. The data presented here indicate that in spite of extensive migratory beekeeping, there is still a large genetic differentiation among honey bee populations. These results should be considered in establishment of conservation plans particularly in moving of colonies between regions. The most importantly introduction of bees with foreign origin and distribution queen bees from one center to all over the country which will homogenize the gene pool of the populations should be prevented
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Piontek, Daniela. « Tabakkonsum bei Jugendlichen und erwachsenen Risikopopulationen. Einflussfaktoren und Ansätze zu Prävention und Intervention ». Doctoral thesis, Universitätsbibliothek Chemnitz, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200800888.
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Tabakkonsum bei Jugendlichen und erwachsenen Risikopopulationen. Einflussfaktoren und Ansätze zu Prävention und Intervention Die vorliegende Arbeit beschäftigt sich mit den Einflussfaktoren des Tabakkonsums bei verschiedenen Zielgruppen sowie möglichen Ansätzen zur nachhaltigen Beeinflussung des Rauchverhaltens. Die Arbeit besteht aus insgesamt sechs Manuskripten, die in nationalen und internationalen Fachzeitschriften publiziert oder zur Publikation angenommen sind. Diese sechs Beiträge lassen sich zwei Schwerpunkten zuordnen, die inhaltlich die zwei wichtigsten Möglichkeiten zur Reduktion des Tabakkonsums in der Bevölkerung widerspiegeln: die Verhinderung des Neueinstiegs in das Rauchen bei Kindern und Jugendlichen (Prävention) sowie die Förderung des Ausstiegs aus dem Rauchen (Intervention). Im ersten Teil wird im Rahmen eines Reviews sowie zweier Studien untersucht, ob sich verhältnispräventive Maßnahmen an Schulen auf das Rauchverhalten der Schüler auswirken. Im zweiten Teil untersuchen drei Studien die Motivation zur Verhaltensänderung, die Inanspruchnahme von Hilfsangeboten bzw. die Effektivität von Tabakentwöhnung bei Rauchern mit einer Alkoholabhängigkeit, Müttern in der Mutter-Kind-Rehabilitation sowie Patienten mit tabakassoziierten körperlichen Erkrankungen„Smoking in adolescents and adult risk populations. Factors of influence and approaches concerning prevention and intervention” This dissertation is concerned with factors influencing the smoking behaviour of different target groups and potential approaches for lasting changes of these behaviours. The dissertation consists of six manuscripts that are published or accepted for publication in national and international peer-reviewed journals. These six papers refer to two main emphases that reflect the two most important possibilities to reduce tobacco consumption in the population: Prevention of smoking initiation in children and adolescents (prevention), and support for smoking cessation (intervention). In the first part of the dissertation, a literature review and two empirical studies assess the influence of school tobacco policies on the smoking behaviour of students. In the second part, three empirical papers examine motivation to change, utilisation and effectiveness of smoking cessation in smokers with an alcohol dependence, mothers in mother-child rehabilitation and patients with smoking-related physical diseases
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Lazer, Ludmilla Verfasser], et Dieter [Akademischer Betreuer] [Hanelt. « Struktur und Funktion mikrobieller Populationen bei der Aufbereitung von Industrieabwasser / Ludmilla Lazer ; Betreuer : Dieter Hanelt ». Hamburg : Staats- und Universitätsbibliothek Hamburg, 2017. http://d-nb.info/1144485541/34.
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Kerbiriou, Christian. « Impact des changements d'usage sur la viabilité d'une population menacée dans un espace multi-protégé : le Crave à bec rouge (Pyrrhocorax pyrrhocorax) sur l'île d'Ouessant ». Phd thesis, Museum national d'histoire naturelle - MNHN PARIS, 2006. http://tel.archives-ouvertes.fr/tel-00177416.
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L'objectif de cette étude a été d'évaluer la viabilité d'une population de Crave à bec rouge (Pyrrhocorax pyrrhocorax), dans un contexte d'espaces protégés confrontés à de profonds changements d'usages des sols. Cet oiseau, espèce emblématique, est en effet susceptible d'être affecté par les modifications des relations société-nature, telles l'abandon des pratiques agricoles et le développement touristique.L'étude s'est dans un premier temps focalisée sur l'identification des facteurs susceptibles d'influencer les paramètres démographiques de cette espèce. Le nombre de sites de reproduction apparaît comme un facteur très probablement limitant. Le succès reproducteur est quant à lui influencé par la superficie d'habitats favorables à proximité des sites de reproduction ainsi que par l'abondance des ressources alimentaires au printemps. Enfin la limitation de l'accès aux zones d'alimentation et la réduction du temps d'alimentation des oiseaux, occasionnées par la fréquentation touristique estivale du littoral, affectent la survie des jeunes Craves.
Dans un second temps, la viabilité démographique de cette population a été évaluée à l'aide de différents modèles et au travers de comparaisons de différents scénarios plausibles d'évolution et d'impacts des activités humaines. Dans l'éventualité d'une stabilisation de la fréquentation touristique et du processus d'enfrichement aux niveaux actuels, la population semble viable. Mais comparativement au contexte passé particulièrement favorable, la population semble désormais sur "le fil du rasoir", une diminution même légère d'un des paramètres démographiques conduirait à une extinction inéluctable. Compte-tenu des dynamiques actuelles, le dérangement touristique estival semble impacter le plus la population à court terme. Différents scénarios de gestion ont donc été envisagés, via notamment un modèle démographique spatialement explicite, développé au sein d'un Système Multi-Agents.
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Bertrand, Bénédicte. « Analyse de la diversité moléculaire de populations d'abeilles de la lignée ouest-méditerranéenne (Apis mellifera mellifera) dans le but de la conservation ». Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00951288.
Texte intégralRésumé :
L'abeille mellifère (Apis mellifera, L.) est divisée en quatre lignées évolutives (M : Ouest-Méditerranéenne, A : Africaine, C : Nord-Méditerranéenne et O : Orientale), elles-mêmes divisées en au moins 26 sous-espèces. Ces lignées et sous-espèces Sont caractérisées par une très forte structuration géographique. Cette structure est le fruit de milliers d'années d'évolution (depuis les dernières glaciations jusqu'à nos jours).Parmi les différentes sous-espèces, on distingue notamment Apis mellifera mellifera (A. m. mellifera), également connue sous le nom de " Abeille noire ". Cette sous-espèce est naturellement présente en France et en Europe du Nord.Pour diverses raisons, des sous-espèces non locales, appartenant en particulier à la lignée C sont importées depuis les années 60 en France.Ces importations, souvent massives, ont tendance à déstructurer la répartition géographique de l'espèce et pourraient mener à une perte de la sous-espèce locale et de ses caractéristiques spécifiques.Des conservatoires d'A. m. mellifera, gérés par des associations d'apiculteurs, ont progressivement vu le jour en Europe, pour limiter les effets des importations. Toutefois, aucun " cahier des charges ", couplant l'aspect scientifique de la conservation avec l'apiculture, n'a encore été émis.La présente thèse a donc permis, par l'étude de congrégation de mâles d'abeilles, de caractériser et valider des conservatoires Européens.Un protocole, quant à la mise en place et au suivi scientifique ainsi qu'apicole de ces conservatoires a été proposé.Enfin, une étude préliminaire du fonctionnement reproducteur d'une population d'abeilles a été menée en Ile-de-France. Cette étude a été entreprise dans le but d'apporter de nouvelles informations pour les programmes de conservation de l'espèce et de l'Abeille noire.Il ressort de cette thèse que la majorité des conservatoires étudiés présentent un niveau d'introgression (par la lignée Nord-Méditerranéenne) suffisamment faible et une diversité génétique suffisante pour être acceptés comme conservatoires. Il faut cependant maintenir le faible niveau d'introgression, d'une part, et, d'autre part, la diversité génétique suffisante, ces critères étant indispensable pour tout conservatoire d'A. m. mellifera.Il apparait également que l'isolement géographique n'est pas obligatoire, voire même non recommandé, pour l'établissement d'un conservatoire. Mais, il est important de caractériser l'ensemble des populations situées autour des zones conservatoires. Cette caractérisation a, en effet, pour but d'estimer et de limiter les risques d'introgression par des colonies non locales.Plusieurs hypothèses émises au cours de cette analyse réfuteraient les conclusions proposées dans des études précédemment réalisées sur l'espèce A. mellifera.En effet, il semblerait que les " faux bourdons " ne se rendent pas à la congrégation de mâles la plus proche. Toutefois, une étude plus approfondie du comportement reproducteur doit être réalisée afin de valider ou d'infirmer cette hypothèse.Enfin, des essaims naturels pourraient être présents dans la région Ile-de-France. Ces essaims étaient considérer comme complètement disparus, à cause de l'invasion du parasite Varroa destructor en Europe. Cette nouvelle hypothèse doit cependant être confirmée par d'autres analyses plus approfondie. La présence de ces essaims naturels serait très encourageante pour la conservation d'A. m. mellifera, mais également de l'espèce en générale.
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Carvalho, Maristela Ferreira Catão. « A polifarmácia em idosos no município de São Paulo - Estudo SABE - Saúde, Bem-estar e Envelhecimento ». Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/6/6132/tde-05122007-083756/.
Texte intégralRésumé :
Introdução: O crescente aumento da população idosa faz aumentar a necessidade de recursos de saúde, entre eles o uso de medicamentos.Objetivo: Estudar os riscos de polifarmácia em idosos no município de São Paulo, Brasil. Métodos: Este estudo faz parte do projeto SABE Saúde,Bem-estar e Envelhecimento através de questionários por amostra em domicílios de 2143 idosos com 60 anos e mais composta por sorteio. Os dados finais foram ponderados e expandidos de modo que representem a população idosa no ano de 2000. A polifarmácia foi definida como o uso de quatro ou mais medicamentos, e utilizado o estudo de regressão logística por passos (IC 95%). Resultados: A média do número de medicamentos foi de 2,72 e a prevalência de polifarmácia de 31,5%. A polifarmácia foi mais prevalente em mulheres com 75 anos e mais (52,1%), religião espírita(51,2%), que declaram estado de saúde ruim (40,2%) e escolaridade acima de 12 anos (46,9%). Verificou-se que 71,1% adquirem medicamentos do próprio bolso, 15,95% se automedicam e a não adesão é devida ao custo (9,1%). Os riscos para polifarmácia foram mulheres (OR 2,2), idade acima de 75 anos (OR 1,5), consulta e internação em quatro meses (OR de 1,9 e 3,8) e problemas cardíacos (OR 3,8). Quanto ao medicamento impróprio a prevalência foi de 15,6%. Conclusão: Os riscos identificados na polifarmácia mostram uma necessidade de políticas públicas que visem promover o uso racional de medicamentos.Introduction: The continuous growth of the elderly population increases the need for further health resources; amongst them is the use of drugs.Object: Study the risks Polypharmacy in the population of elderly people within the city of São Paulo, Brasil. Method: This study is part of the SABE project Health, Well-being and aging. This survey is carried out by using a sample questionnaire in the residence of 2143 people aged 60 and over. The final data are pondered and expanded to represent the population of elderly people in the year 2000. In order to analyze, polypharmacy was defined as four or more drugs, using the study of stepwise logistical regression (IC95%). Results: The average number of drug stays at 2,72, with a prevalence of polyfarmacy of 31,5%. Polyfarmacy is more prevalent amongst women aged 75 and over (52,1%); spiritualists (51,2%); those who claim poor self perceived health status (40,2%); those whose level of education is at least 12 years (46,9%). It has been observed that 71,1% use their own money to buy drugs; 15,9% practice self-medication; the cost of treatment being the cause of nonadherence (9,1%). Women are more at risk (OR 2,2), aged 75 and over (OR 1,5), visit to the physician and hospitalization within four months(OR from 1,9 to 3,8), cardiovascular conditions (OR 3,8). As for inappropriate use of medications, the prevalence is 15,6%. Conclusion: The identified risks in polypharmacy show a need for public policies that would promote a more rational use of medications.
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Cardoso, Pedro Filipe Menezes. « Colonização e dispersão nos sítios de ocorrência, a genética das populações e história natural de Partamona ailyae Camargo, 1980 (Hymenoptera : Apidae : Meliponini) ». Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8500.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Particular biological features of different bee groups can affect how a certain area will be occupied by them and this can affect directly the genetics of their populations over the long term. In Brazil, there are few studies about gene variation and genetic structure of bee natural populations, as well as on the genetic differentiation levels between eusocial bee populations. The Partamona genus comprises 33 species, distributed from Southern Mexico to Southern Brazil. Partamona ailyae, the model species of this study, occurs in rainforests of Southwestern Amazonia, Central Brazil and xeric regions of Piauí. Its wide distribution, as well as the ability to occupy such heterogeneous environments, piqued our interest to take P. ailyae as a study model. This work aimed to analyze the occupation process at the P. ailyae occurrence sites, population genetics and interpopulational gene flow, and the natural history of this species. Eight expeditions were carried out, and 41 localities of 10 states of Brazil were visited. Among them, active colonies of P. ailyae were found only in 17 localities, being collected specimens of 75 nests. To identify the mitochondrial lineages present in the sampled colonies, five gene regions were used (COI, CytB, 12S, 16S and COI-COII). Estimates of polymorphism levels showed COI and CytB as the most variable regions (11 and seven haplotypes, respectively). For the ribosomal genes, only a few samples were analyzed, because few differences were identified among the sequences. All the 31 samples analyzed for the 12S showed a five bases insertion starting from the position 25 of the sequence, a result not observed in other Partamona species. The most informative genes (COI and CytB) had their sequences concatenated (1114pb). For these regions, 13 haplotypes were observed, two of them were shared and 11 characterized as exclusive of localities. The AMOVA showed that 94.3% of the gene variation is due to interpopulacional differences, revealing a high differentiation among the populations (ΦST = 0.9426; P = 0.000). In addition, one individual from each colony was analyzed for eight heterologous microsatellite loci designed from Melipona bicolor and Partamona helleri. A moderate and statistically significant XIV interpopulational genetic differentiation (ΦST = 0.1491; P = 0.000) was found. The cluster analysis identified four groups by ΔK as the ideal model, and STRUCTURE software showed that all individuals could belong to more than one group, corroborating the “Assignment test”, which indicated that only 50% of the samples were correctly assigned to their original population. Phenotypic segregation analysis was realized in some offsprings, revealing a monoginic/monandric familial structure. From the mitochondrial data, the Mantel test showed a significant correlation between genetic distance and geographic distance (r = 0.2589; P = 0.0231), whereas on basis of the nuclear data, the Mantel test did not indicate significant correlation between genetic distance and geographic distance (r = 0.2090; P = 0.0610). Fu’s Fs and R2 tests did not show significant values. The Bayesian Skyline Plot analysis (BSP) did not show significant fluctuations in the effective size populations of P. ailyae, indicating population stability over time. The values of ΦST estimated for mitochondrial genes and microsatellites were compared, being detected evidence of sex-asymmetric dispersal, in which females are responsible for the areas occupation, and males constitute the disperser sex. In addition, some relevant aspects of the natural history of P. ailyae are shown.
Características inerentes à biologia dos diferentes grupos de abelhas podem afetar como uma determinada área será ocupada e isso pode influenciar diretamente a genética de suas populações no longo prazo. No Brasil, poucos são os estudos que tratam da variabilidade e estrutura genéticas das populações naturais de abelhas, assim como os níveis de diferenciação entre as populações de abelhas eussociais. O gênero Partamona compreende 33 espécies descritas, distribuídas do sul do México ao sul do Brasil. Partamona ailyae ocorre nas matas úmidas do sudoeste da Amazônia, região central do Brasil e regiões xéricas do Piauí. A sua grande distribuição, bem como a capacidade de ocupar ambientes tão heterogêneos, despertou nosso interesse em utilizar P. ailyae como modelo de estudo. O objetivo deste trabalho foi analisar o processo de ocupação nos diversos sítios de ocorrência de P. ailyae, a genética de suas populações e o fluxo gênico interpopulacional; adicionalmente, conhecer um pouco da história natural da espécie. Foram realizadas oito expedições, sendo visitadas 41 localidades de 10 estados brasileiros. Dentre estas localidades, em apenas 17 foram encontradas colônias ativas de P. ailyae, sendo coletados espécimes de 75 ninhos. Para identificar as linhagens mitocondriais presentes nas localidades amostradas, cinco regiões gênicas foram utilizadas (COI, CytB, 12S, 16S e COI-COII). Os níveis de polimorfismo estimados neste estudo mostraram COI como a região mais variável (11 haplótipos), seguido de CytB (sete haplótipos). Para os genes ribossomais, apenas algumas amostras foram analisadas, pois foram identificadas poucas diferenças entre as sequências. Todas as 31 amostras analisadas para o gene 12S apresentaram repetição/inserção de cinco bases a partir da posição 25 da sequência, resultado não observado nas demais espécies de Partamona analisadas. Os genes que forneceram maiores informações (COI e CytB) tiveram suas sequências concatenadas (1114pb) e para estas regiões, foram observados 13 haplótipos; destes, dois foram compartilhados e 11 caracterizados como exclusivos de localidades. A AMOVA demonstrou que 94,3% da variação genética é resultado de diferenças interpopulacionais, revelando uma XII elevada diferenciação entre as populações analisadas (ΦST = 0.9426; P = 0,000). Além disso, um indivíduo de cada colônia foi analisado para oito locos microssatélites, delineados para Melipona bicolor e Partamona helleri. As populações apresentaram moderada diferenciação interpopulacional (ΦST = 0,1491; P = 0,000). A análise de agrupamento identificou quatro grupos por meio do ΔK como sendo o modelo ideal, e através do STRUCTURE, foi verificado que todos os indivíduos das respectivas populações têm probabilidade de pertencer a mais de um grupo, corroborando o “Assignment test”, o qual indicou que apenas 50% das amostras foram corretamente identificadas à sua população de origem. Foi realizada análise da segregação fenotípica nas progênies de vários ninhos, revelando uma estrutura familial monogínica/monândrica. Para os dados mitocondriais, o teste de Mantel mostrou uma correlação significativa entre distância genética e distância geográfica (r = 0,2589; P = 0,0231). Já para os dados nucleares, esse teste não indicou correlação significativa entre as distâncias genéticas e geográficas (r = 0,2090; P = 0,0610). Os testes de Fs de Fu e R2 não apresentaram valores significativos. Na análise do Bayesian Skyline Plot (BSP), não foram observadas oscilações marcantes no tamanho efetivo das populações de P. ailyae, indicando estabilidade populacional ao longo do tempo considerado. Os valores do ΦST estimados para genes mitocondriais e para os microssatélites foram comparados, sendo detectadas evidências de dispersão sexo-assimétrica, em que as fêmeas são as responsáveis pela ocupação de áreas, e os machos constituem o sexo dispersor. Além disso, são apresentados alguns aspectos relevantes da história natural de P. ailyae.
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Natividade, Yuri Pereira Efrem. « Seleção genômica multirracial em bovinos de corte ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-12122017-101524/.
Texte intégralRésumé :
A seleção genômica é a mais moderna tecnologia no que tange a utilização de marcadores genéticos para a seleção e melhoramento genético de animais domésticos. Em síntese a metodologia consiste em uma seleção assistida por marcadores em uma escala ampla do Genoma e foi proposta por Meuwissen et al. (2001). O desequilíbrio de ligação (DL) entre os marcadores e loci de características quantitativas (QTL) e a composição da população referência são pontos chave para a confiabilidade da seleção genômica. À medida que os indivíduos se distanciam geneticamente, o DL entre marcadores e QTL diminui, o que dificulta a aplicação da seleção genômica em populações de animais multirraciais e explica o fato de até hoje a maior parte das pesquisas se concentrarem na estimação de valores genômicos apenas para animais de raças puras. A aplicação dessa metodologia em populações multirraciais de bovinos constitui uma possibilidade real de grandes avanços no melhoramento genético do rebanho brasileiro de bovinos de corte.Genomic Selection is the newest technology into the use of genetic markers at the animal breeding. In sinthesys the metodology consists in a marker assisted selection in a genome wide scale, it was pourpused by Mewissent et al. (2001). The linkage disequilibrium between the marker and quantitative trait loci (QTL) and the composition of the reference population are key points to the reablility of the genomic selection. Once the individuals get genetically distants, the DL between markers and QTLs decays, what turns hard the aplication of genomic selection in multirracial populations of animals and explains the fact of untill today the major part of researchs are dedicated to the estimation of genomic breeding values only to purebreed animals. The aplication of this methodology in multibreed cattle populations consists in a real possibility to reach greats advances in genetic improvement of the brazilian beef cattle heard.
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Pacoureau, Nathan. « Influence de la variabilité climatique, de l’abondance de proies, de la densité-dépendance et de l'hétérogénéité individuelle chez des prédateurs supérieurs longévifs : de l’individu à la population ». Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS026/document.
Texte intégralRésumé :
Une question fondamentale en écologie des populations est l’identification des facteurs influençant la dynamique d’une population. L’objectif principal de cette thèse est de déterminer quelles sont les réponses démographiques et populationnelles de prédateurs marins supérieurs face aux fluctuations d’abondance de leurs proies, aux variations climatiques, à la densité-dépendance tout en tenant compte de l’hétérogénéité inter et intra-individuelle (âge, expérience, sexe, qualité ou stratégie). Pour ce faire, nous nous baserons sur l’analyse de suivis à long-terme individuels et populationnels d’oiseaux marins longévifs et prédateurs apicaux phylogénétiquement très proches dans deux biomes contrastés : le labbe de McCormick Catharacta maccormicki sur l’archipel de Pointe Géologie en Antarctique et le labbe subantarctique Catharacta lonnbergi sur l’archipel des Kerguelen en milieu subantarctique. Nous tirerons parti d’estimations d’abondances de leurs proies respectives : le manchot Adélie Pygoscelis adeliae et le manchot empereur Aptenodytes forsteri en Antarctique, et le pétrel bleu Halobaena caerulea et le prion de Belcher Pachyptila belcheri à Kerguelen. Ces jeux de données offrent une opportunité unique de pouvoir déterminer et quantifier simultanément les différentes sources de variabilité dans les changements de taille de populations naturelles occupant l’un des niveaux trophiques les plus élevés des réseaux alimentaires antarctiques et subantarctiques. Nous avons mis en évidence de la variation dans plusieurs traits vitaux des deux populations influencées par les performances des individus et de l’hétérogénéité individuelle latente. Nous discutons des mécanismes par lesquels la variabilité climatique, l’abondance de proie et la densité de population peuvent affecter différentiellement les différentes classes d’âges de chaque trait vital, et les conséquences potentielles de futurs changements environnementauxA fundamental endeavor in population ecology is to identify the drivers of population dynamics. The main objective of this thesis is to determine what are the demographic and population responses of superior marine predators to the fluctuations of their prey abundance, to climatic variations, to density-dependence while taking into account inter and intra individual heterogeneity (age, experience, sex, quality or strategy). To do this, we analysed long-term individual and population-based monitoring of long-lived seabirds and phylogenetically close apical predators in two contrasting biomes: the south polar skua Catharacta maccormicki at Pointe Géologie archipelago, Antarctica, and the brown skua Catharacta lonnbergi on the sub-Antarctic Kerguelen Archipelago. We will use direct abundance of their respective prey: Adélie penguin Pygoscelis adeliae and emperor penguin Aptenodytes forsteri in Antarctica, and the blue petrel Halobaena caerulea and the thin-billed prion Pachyptila belcheri prion in Kerguelen islands. These datasets provide a unique opportunity to simultaneously disentangle and quantify the different sources of variability driving variation in natural populations occupying one of the highest trophic levels of the Antarctic and sub-Antarctic food webs. We found variation in several vital traits of both populations influenced by individual performance and latent individual heterogeneity. We discuss the mechanisms by which climatic variability, prey abundance, and population density can differentially affect the different age classes of each age class, and the potential consequences of future environmental changes
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Moulton, J. K., D. A. Pepper et T. J. Dennehy. « Studies of Resistance of Beet Armyworm (Spodoptera exigua) to Spinosad in Field Populations from the Southern USA and Southeast Asia ». College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/219978.
Texte intégralRésumé :
Susceptibility to spinosad (Success®/Tracer®) of beet armyworm (Spodoptera exigua) from the southern U.S.A. and Southeast Asia was determined through exposure of third instar larvae to dipped cotton leaves. LC₅₀ values of field populations ranged from 0.6 to 14 μg spinosad/ml. Field populations were 3.0 to 70-fold less susceptible to spinosad than was a susceptible reference population. The least susceptible population was collected from Thailand. We hypothesized that this population was resistant to spinosad because: (1) it was significantly less susceptible to spinosad than all other populations evaluated and than any other reports in the literature; (2) it regained susceptibility while in culture; (3) it was collected from a region of very intensive insecticide use and severe insect resistance problems; and (4) it exhibited significant survivorship on field-treated cabbage leaves. Piperonyl butoxide (PBO), diethyl maleate (DEM), and S,S,S tributyl-phosphorothiolate (DEF) failed to synergize spinosad in this resistant Thailand population, and PBO failed to do so in the least susceptible domestic population evaluated, the Parker, AZ, field strain. However, the synergist and field residue studies were conducted using a Thailand population that had levels of resistance that declined while in laboratory culture.