The Yellow Warbler (Dendroica petechia) is a highly polytypic bird species with a vast breeding range in the Americas. To assess the level of population structuring within the northern part of its range, I surveyed the nucleotide variation present in a 344bp segment of the mitochondrial DNA (mtDNA) control region I (CR-I) from 155 breeding individuals. These birds were caught at seven locations in Canada and Alaska. Fifty-nine haplotypes were observed in this sample, with pairwise distances between haplotypes ranging from 0.29 to 4.35%. The number of nucleotide sites with multiple hits indicates a high rate of evolution in this region. A homologue to the CR-I was also identified and likely originated from a paralogous duplication event, as suggested by the comparison of sequences from the two regions. Significant population structuring in Yellow Warblers across North America was revealed by analyses of nucleotide diversity and molecular variance, which demonstrated the existence of a major subdivision between eastern (Manitoba to Newfoundland) and western (Alaska and British Columbia) warbler populations. This finding provides evidence for very low levels of gene flow between these two groups. Fifteen out of 21 pairs of populations differ significantly in their genetic composition, indicating further structuring at a smaller geographic scale. Within the eastern group of populations, both the high mutation rate of the CR-1 and an isolation-by-distance process seem to be responsible for differences between locations. Phylogenetic analyses indicate that western birds form a monophyletic group whereas eastern birds are paraphyletic with respect to the western ones. However this conclusion remains hypothetical because of a lack of statistical support for the monophyly of western haplotypes. Nevertheless, this situation is consistent with a historical splitting of warbler populations by a vicariant event, possibly of Pleistocene origin, and provides intraspecific support for vicariance as a mechanism leading to isolation and speciation of western warbler taxa, as hypothesized by Mengel (1964). However, other scenarios, such as a founder event in the west from an eastern stock, cannot be excluded, although they are less likely based on mtDNA data. The absence of phylogeographic structure in the East suggests a recent expansion of Yellow Warbler populations from a restricted geographic range. These findings demonstrate that populations of continentally distributed North American passerine species can show high level of population structuring when assayed with an hypervariable molecular marker such as the mtDNA control region I. / Thesis / Master of Science (MSc)

Nine, production-scale, recirculating aquaculture systems were utilized to compare the growth parameters between all-female and mixed sex yellow perch stocks. Each system was stocked with 455 fish m⁻³ and contained one of three different biofilter types: a rotating biological contactor, a trickling filter or a bead filter. The all-female fingerlings (S1) used were originally derived from Lake Mendota, Wisconsin. The mixed-sex fingerlings (S2) used were originally derived from Lake Erie. Temperature and photoperiod (23°C, 16H-L) were maintained at levels for optimal growth. Absolute growth rates ranged from 0.27-0.48 g/day. Mean final density within treatments was 42.8 kg/m³ and ranged from 37.2-50.2 kg/m³. The main effect of stock did not have a significant effect on growth (p > .1). All-female treatments exhibited more uniform growth. The main effect of filter type did have a significant effect on fish growth (p < .01), with fish in tanks containing trickling filters exhibiting significantly higher growth. Total feed conversion averaged 1.61 across all treatments and ranged from 1.38-1.78. S1 treatments consumed a significantly higher percent body weight per day than S2 treatments (p < .05). Analysis of PIT tagged individuals revealed that the mean relative growth rate was significantly higher in S2 individuals (513.9%) compared to S1 individuals (315.3%: p < .01). S2 females (597.8%) grew 1.9 times faster than S1 females (315.3%: p < .01). Within S2 individuals, females (597.8%) grew 1.5 times faster than males (395.2%: p < .05). For all individuals, 33.6% of the variation in final weight was explained by the variation in initial weight. Differences in the geographic strain or culture history of these stocks may have had a larger overall effect on growth than sexual classification (all- female or mixed sex). Dress percentage of skin-on butterfly fillets was examined in 20 individuals per stock and in six groups of 20 individuals per stock. Within S2 individuals, 73.7% were female. Mean fillet yield was significantly greater in S1 individuals (47.6%) compared to S2 individuals (43.0%: p < .01). Mean GSI in S1 individuals (1.01%) was significantly higher than S2 individuals (0.54%: p < .05). Within S2 individuals, mean GSI was significantly higher in females (0.70%) when compared to males (0.08%: p < .05). Fillet yield was significantly greater in S1 groups (47.2%) compared to S2 groups (44.9%: p < .01). Within each stock fillet yield increased with size. The difference in fillet yield demonstrated between these stocks may be a result of differences in strain of origin. The identification of superior yellow perch strains or strain crosses with regard to growth rate and fillet percentage is of considerable importance to the industry. / Master of Science

Para avaliar os possíveis efeitos que os corantes artificiais podem causar à saúde, é de grande importância possuir dados relativos à exposição a estas substâncias. O fato de diversos estudos apontarem problemas de saúde relacionados ao consumo do corante artificial Amarelo Crepúsculo (AC) justifica a necessidade de verificar se a ingestão desta substância, através do consumo de alimentos industrializados, ultrapassa a Ingestão Diária Aceitável (IDA). O objetivo deste trabalho foi estudar e caracterizar a ingestão de AC pela população brasileira. Para isso, primeiramente foram verificados quais os alimentos comercializados por uma das maiores redes de supermercados do país que continham AC na sua formulação. Foi avaliada a ingestão média destes alimentos utilizando as Pesquisas de Orçamento Familiar (POF, 2008-2009) e determinada a Ingestão Diária Máxima Teórica (IDMT) de AC, através dos valores estipulados pela legislação brasileira para a concentração máxima permitida deste corante nos diferentes grupos de alimentos. Posteriormente foram realizadas analises, através de Cromatografia Líquida de Alta Eficiência (CLAE), para avaliar o teor de Amarelo Crepúsculo em refrescos em pó, refrigerantes, bebidas isotônicas, gelatinas e balas, e verificar as faixas de utilização deste corante e a adequação à legislação vigente. Através dos dados obtidos, verificou-se que a IDMT para AC, considerando o consumo médio per capita de alimentos, não supera a IDA para nenhuma das distribuições populacionais estudadas. No entanto, ao considerar a prevalência de consumo alimentar, a IDMT é superior à IDA para adolescentes de 10 a 18 anos (277% da IDA), adultos (181% da IDA) e idosos (140% da IDA) das áreas urbanas e rurais e nas cinco regiões do país Em relação às amostras analisadas, pode-se constatar que, considerando-se as médias obtidas, os produtos que mais contêm AC são na ordem: Refrigerantes (7,91 mg/100 mL); Bebidas Isotônicas (6,22 mg/100 mL); Refrescos em pó (5,96 mg/100 mL); Gelatinas (5,92 mg/100 mL) e Balas (menor que 1,25 mg/100 g). Através da realização deste trabalho, conclui-se que considerando o consumo médio per capita a ingestão diária representa entre 14 e 31% da IDA, não representando risco à saúde. No entanto, verificou-se que alguns indivíduos de todos os grupos populacionais podem estar ingerindo o corante em quantidades superiores às recomendadas. Cabe destacar que a POF (2008-2009), utilizada como fonte de dados nesta pesquisa, entrevistou crianças a partir dos 10 anos de idade. Visto que neste estudo o consumo de AC aumentou ao diminuir a faixa etária, é provável que esta tendência se aplique para crianças com menos de 10 anos. Diante do exposto, torna-se necessário um maior rigor no emprego e na fiscalização do uso de Amarelo Crepúsculo em produtos alimentares, visto que o consumo elevado deste corante pode ocasionar reações adversas aos seus consumidores. / To evaluate the possible effects that artificial dyes can cause health is very important to have data on exposure to these substances. The fact that several studies suggest health problems related to the consumption of artificial dye Sunset Yellow (SY) justifies the need to verify that the ingestion of this substance through consumption of processed foods, exceeds the Acceptable Daily Intake (ADI). The aim of this study was to evaluate and characterize the SY intake by the Brazilian population. For this, they were first checked which foods marketed by one of the country's largest supermarket chains containing SY in its formulation. the average intake of these foods using the Household Budget Surveys were evaluated (HBS 2008-2009) and determined the Theory Maximum Daily Intake (TMDI) SY, through the values set by the Brazilian legislation for the maximum permitted concentration of the dye in the different groups of food. Later analyzes were performed by High Performance Liquid Chromatography (HPLC) to evaluate the Yellow Twilight content in powdered drinks, soft drinks, isotonic drinks, gelatins and candy, and check the use of bands of this dye and the adequacy of legislation current. Through the data, it was found that the TMDI for SY, considering the average per capita consumption of food does not exceed the ADI for any of the studied population distributions. However, when considering the prevalence of food consumption, the TMDI is higher than the ADI for adolescents 10-18 years (277% of ADI), adults (181% of ADI) and the elderly (140% ADI) in urban areas and rural and in five regions of the country. Regarding the samples, it can be seen that, considering the averages, the products that contain SY are in order: Soft drinks (7.91 mg/100 mL); Isotonic drinks (6.22 mg/100 mL); powdered drinks (5.96 mg/100 mL); Gelatins (5.92 mg/100 mL) and candy (below 1,25 mg/100 g) Through this work, it is concluded that considering the average consumption per capita daily intake is between 14 and 31% of ADI and do not represent a health risk. However, it was found that some individuals of all population groups may be ingesting the dye in amounts greater than those recommended. It should be noted that the HBS (2008-2009), used as a data source in this research, interviewed children from 10 years old. Since in this study the use of SY increased by reducing the age, it is likely that this trend will apply to children under 10 years. Given the above, it is necessary a greater rigor in applying and monitoring the use of Sunset Yellow in food products, as the high consumption of this dye can cause adverse reactions to their consumers.

Bibliography: leaves 118-132. This thesis examines the structure and gene expression of barley yellow dwarf viruses (BYDVs)-PAV in order to gain a better understanding of the interaction between the virus and the Yd2 resistance gene. The protein products of open reading frame (ORF)3, ORF4 and ORF5 are expressed in bacterial cells, in order to characterise the BYDV-PAV virion-associated proteins. The effect of the Yd2 resistance gene on the expression of the BYDV-PAV viral proteins in infected cells is also studied.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Dissertation (Ph.D.)--Auburn University, 2009. / Abstract. Includes bibliographic references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Yellow perch Perca flavescens spawning was evaluated in southern Lake Michigan during 2009 to determine the timing, location, and extent of spawning activity. Maturity state (i.e., pre-spawn/post-spawn), gonadosomatic index (GSI), mean length, length frequency distributions, and sex group proportions were also evaluated. No egg skeins were discovered during the study. The GSI decreased during the duration of the spawn. Spent females were larger than pre-spawn females. Following the spawning season another assessment was conducted to determine whether differences existed in the spawning and post-spawning population demographics. Abundance, length frequency distributions, proportions, and relative stock density were evaluated. Abundance of fish in the post-spawning period increased six-fold and paralleled a shift in length frequency distribution to larger median size. An increase in the proportion of females and relative stock density from the spawning period to post-spawning period was discovered. These data infer adult fish were spawning elsewhere, and then migrating to Indiana. / Department of Biology

The Indiana waters of Lake Michigan were sampled weekly from May until August in 2009, 2011, and 2012 to determine the extent of yellow perch reproduction and the role Indiana waters play in yellow perch life history. Experimental gill nets were used to collect fish before, during, and after the spawning season from randomly selected sites along the Indiana shoreline. Yellow perch were then taken to an onshore processing station where they were weighed, measured, and visually examined to determine sex and maturity. Maturity stages of adult yellow perch were used to estimate the timing and duration of yellow perch spawning. Yellow perch population demographics were also compared to determine if different groups of yellow perch were present before and after the spawn. My data suggests that yellow perch spawning is strongly influenced by temperature and that Indiana waters are seasonally used by adult yellow perch for feeding. / Department of Biology

Bibliography: leaves 118-132. / iv, 132 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis examines the structure and gene expression of barley yellow dwarf viruses (BYDVs)-PAV in order to gain a better understanding of the interaction between the virus and the Yd2 resistance gene. The protein products of open reading frame (ORF)3, ORF4 and ORF5 are expressed in bacterial cells, in order to characterise the BYDV-PAV virion-associated proteins. The effect of the Yd2 resistance gene on the expression of the BYDV-PAV viral proteins in infected cells is also studied. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997