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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Genetic parameters of production traits in Welsh mountain sheep

Saatchi, Mustafa January 1998 (has links)
No description available.
2

Adaptação de parâmetros em meta-heurísticas com sistemas nebulosos genéticos / Parameter adaptation of metaheuristic with genetic fuzzy systems

Marques, Vitor Hugo Almeida 18 August 2018 (has links)
Orientador: Fernando Antônio Campos Gomide / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-18T11:42:14Z (GMT). No. of bitstreams: 1 Marques_VitorHugoAlmeida_M.pdf: 2517224 bytes, checksum: e0259e1018ac57ec9a5cb95e0d65284b (MD5) Previous issue date: 2011 / Resumo: Esta dissertação introduz um sistema nebuloso genético (SNG) para adaptação de parâmetros em meta-heurísticas. Duas meta-heurísticas entre as mais usadas foram consideradas como exemplos, algoritmo genético e busca tabu. Os parâmetros trabalhados na busca tabu são relacionados às memórias, de curto prazo e de longo prazo. Já os parâmetros do algoritmo genético a sofrer adaptação são as taxas de reprodução e mutação. Sistemas baseados em regras nebulosas oferecem um mecanismo natural para descrever comportamentos globais como combinação de regras de controle. Eles também herdam um meio de gradualmente alternar entre regras que conjuntamente definem uma estratégia de controle. Dessa forma, esses sistemas são candidatos naturais para construir estratégias de controle de parâmetro porque eles proveem um maneira de desenvolver mecanismos baseados na natureza específica de uma região de busca e as transições entre suas fronteiras. Uma aplicação usando o problema clássico de roteamento de veículos com janela de tempo foi incluído para avaliar o desempenho do sistema nebuloso genético. Resultados experimentais mostram que meta-heurísticas com o mecanismo de adaptação com SNG melhoram o comportamento da busca e a qualidade das soluções quando comparado à versões padrões ( sem SNG ) e com parâmetros constantes dos algoritmos genético e busca tabu. Eles também geram boas soluções sub-ótimas mais rápidas que métodos exatos desenvolvidos para o problema e que são reportados na literatura / Abstract: This dissertation introduces a genetic fuzzy system for parameter adaptation of metaheuristics. Two metaheuristics, among the most used ones, have been considered as examples, genetic algorithm and tabu search. The considered parameters of the tabu search are related to the short and long term memories. Parameters of the genetic algorithm under adaptation are the mutation and reproduction rates. Fuzzy rule-based models offer a natural mechanism to describe global behavior as a combination of control rules. They also inherit a means to gradually shift between control rules which jointly defines a control strategy. They are a natural candidate to construct parameter control strategies because they provide a way to develop decision mechanisms based on the specific nature of search regions and transitions between their boundaries. An application using the classic vehicle routing problem with time windows is included to evaluate the genetic fuzzy system performance. Experimental results show that metaheuristics with GFS improve search behavior and solution quality when compared against standard, constant parameters genetic and tabu search approaches. It also provides reasonably good suboptimal solutions faster than specially tailored exact methods reported in the literature / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica
3

An Analysis of Farm-Level Performance of Shallow Loss Products based on Aggregated Farm Yields Case Study of the Stacked Income Protection Plan (STAX)

Yehouenou, Lauriane Senade Massan 12 August 2016 (has links)
The STAX and SCO shallow loss crop insurance products were introduced in the 2014 farm bill. This research investigates the farm-level performance of STAX for cotton growers. Using 10 years of actual farm yield data for the period 1999 to 2008, certainty equivalent gains were evaluated under four treatments in Texas, Mississippi and Louisiana for non-irrigated and irrigated cotton production. Following the current practice for STAX, county yield is estimated using yield data from YP, RP, and RP-HPE policies rather than NASS county level yield data. Findings show that, assuming actuariallyair premiums, certainty equivalent gains for RP tend to be higher than for STAX. But with subsidized premiums, the opposite outcome sometimes occurs. Furthermore, with subsidized premiums the findings indicate that almost all farms would benefit from purchasing STAX as a complement to RP. The use of actual farm yield data highlights the heterogeneity of STAX farm-level impacts.
4

The Effect of Urinary Cadmium on Cardiovascular Fitness as Measured by VO2 Max in White, Black and Mexican Americans

Egwuogu, Heartley 31 July 2007 (has links)
Context: Cadmium is an important predictor of lung function, including forced vital capacity, forced expiratory volume and peak flow. Current evidence supports the notion that cadmium may be an important risk factor for cardiovascular fitness. Objectives: The purpose of this study was to determine the effect of cadmium exposure on cardiovascular fitness in representative sample of US white, blacks and Mexican Americans. The study also sought to determine if the relationship between cadmium and cardiovascular fitness varies by gender and racial/ethnic group. Methods: The data utilized for this study were obtained from National Health and Nutrition Examination Survey (NHANES). One-thousand nine hundred and sixty three subjects with data on cardiovascular fitness were eligible for this investigation. In NHANES, cardiovascular measurements were taken in series consisting of two minutes warm up exercise, two-three minutes exercise testing and two minutes resting period .The goal was to elicit 75% of predetermined age-specific heart rate by the end of the stress test. Cadmium was measured in the laboratory by taking urine sample of participants. Gender and race/ethnic specific multivariate linear regression analyses were performed to determine relationship of urinary cadmium with VO2 max. Results: There were gender and racial/ethnic difference in the relationship between urinary cadmium and VO2 max. In males and females, increased concentration of urinary cadmium was associated with decreased VO2 max across racial/ethnic groups (except in black males. The greatest negative association between cadmium and VO2 max was observed in black females (beta=-0.330) while the lowest value was recorded for white females (Beta=-0.074). The association was statistically significant in white males (Beta=-0.402, P =0.020) and Mexican American females (Beta=-0.290, P=0.026). Conclusion: There was inverse association between urinary cadmium and estimated VO2 max in a US nationally representative sample of White, Black and Mexican Americans. The impact of the gender and racial/ethnic differences in the association between urinary cadmium and VO2 max is not clear and warrants further investigation.
5

The application of Australian-developed performance and genetic technology to the Chinese beef industry

Park, Nigel January 2003 (has links)
In terms of numbers and volume of meat produced, the Chinese beef industry is one of the largest in the world. Development of the industry has only occurred within the last thirty years, and despite extensive cross-breeding programs with imported breeds, performance of Chinese cattle is low, and the industry is still subject to traditional farming methods. This study looks at the Australian-developed genetic evaluation system BREEDPLAN, which is regarded worldwide as one of the best systems for assisting with selection of beef cattle for increased performance by evaluating genetics and identifying superior animals, and asks if BREEDPLAN can be successfully applied to the Chinese beef industry. Issues discussed include the complementarity of BREEDPLAN to existing Chinese breeding programs and the benefits of BREEDPLAN if introduced, as well as opportunities for Australians to provide consultancy services to facilitate introduction. The marketing of Australian genetic material in China, and cross-cultural marketing issues are also considered. Field research was conducted in China using itinerant interviews and observational research, together with unstructured, informal interviews and discussions with Australian beef industry experts. It is found that breed improvement programs in China are controlled by the Ministry of Agriculture, and management practises within the government-run herds make them eminently suitable for the application of BREEDPLAN. The objective measurements of BREEDPLAN would provide observable genetic gain, resulting in increased industry productivity and profitability. In addition, it is found that a need exists within the Chinese beef industry for consultants not only with expertise and knowledge about BREEDPLAN, but also with an understanding of Chinese language and culture, which would be an advantage for dealing with cross-cultural difficulties. Market opportunities for Australian genetic material are considerable, but not unlimited, and further research is required to assess the size of the market. It is recommended that immediate steps be taken to introduce BREEDPLAN to the Chinese beef industry.
6

Diabetic nephropathy in a tertiary clinic in South Africa, a cross-sectional study

Ngassa Piotie, Patrick January 2015 (has links)
Objective: The aim of this study was to determine the prevalence of micro- or macroalbuminuria among type 1 and type 2 diabetic patients and to examine the relationship with diabetes control parameters: haemoglobin A1C (HbA1C), blood pressure (BP) and lipids. Design: Analytical cross-sectional study. Setting and subjects: The study consisted of 754 patients with either type 1 or type 2 diabetes mellitus, attending a diabetic clinic at the Kalafong Hospital in Pretoria, South Africa. Outcome measures: Micro- or macroalbuminuria and estimated glomerular filtration rate (eGFR). Results: Of all patients, 88.9% had HbA1C > 7%, and 81% had low-density lipoprotein (LDL) cholesterol ≥1.8 mmol/l. Overall prevalence of micro- or macroalbuminuria was 33.6%. Logistic regression revealed that HbA1C, duration of diabetes, systolic BP, male sex and triglycerides predicted microalbuminuria. Conclusion: The prevalence of micro- or macroalbuminuria in this study falls within the ranges of what has been previously reported in Africa. In all patients, HbA1C and duration of diabetes were the strongest predictors of microalbuminuria, and age was the strongest predictor of a low eGFR. Diabetes was poorly controlled, making the progression to end-stage renal failure a real concern in these patients. / Dissertation (MPH)--University of Pretoria, 2015. / tm2015 / School of Health Systems and Public Health (SHSPH) / MPH / Unrestricted
7

A Computer Program for Survival Comparisons to a Standard Population

Moon, Steven Y., Woolson, Robert F., Bean, Judy A. 01 January 1979 (has links)
PROPHAZ is a computer program created for the analysis of survival data using the general proportional hazards model. It was designed specifically for the situation in which the underlying hazard function may be estimated from the mortality experience of a large reference population, but may be used for other problems as well. Input for the program includes the variables of interest as well as the information necessary for estimating the hazard function (demographic and mortality data). Regression coefficients for the variables of interest are obtained iteratively using the Newton-Raphson method. Utilizing large sample asymptotic theory, χ2 statistics are derived which may be used to test hypotheses of the form Cβ = 0. Input format is completely flexible for the variables of interest as well as the mortality data.
8

Tax payment-based liquidity effects: using historical evidence of a tax-based January effect to investigate a new seasonal

Cataldo, Anthony J. 10 November 2005 (has links)
This dissertation used the daily Dow Jones Industrial Average (DJIA) for the 1897 through 1928 period to examine the potential existence of any market reactions, which may have resulted from the imposition and expansion of "withholding at the source" and quarterly and estimated tax payments. Providing for a natural laboratory, this period has previously been used to examine and gain insights into tax-loss selling (TLS) as a possible (partial) explanation for year-end changes in stock prices. Drawing from the methodologies and findings from these studies, this period is examined both (1) in its entirety and (2) as partitioned, using two different operational definitions of the pre-/post-tax period. Additional, contemporary period-based analyses were conducted for the 1918 and 1930 through 1994 periods, using both DJIA and Standard & Poor's (S&P) 500 Composite daily indexes, respectively. The focus was on changes in estimated tax payments dates/event windows to determine the contemporary existence of tax-based liquidity effects. Both historical (1897-1928) and contemporary (1930-1989) period evidence is found in support of the existence of a tax payment-based liquidity effect. Evidence developed over the entire period (1897-1994) suggests that this seasonal continues to exist for the April 15 (combined) tax filing and estimated tax payment date. / Ph. D.
9

Fluorescência dental: possível aplicação forense / Fluorescence dental: potential application in forensic science

Silva, Ricarda Duarte da 02 August 2012 (has links)
Nos casos de identificação de ossadas, segmentos do esqueleto ou ossos isolados, buscar o diagnóstico dos dados biotipológicos, como a idade do indivíduo, proporciona a possibilidade de estabelecer uma conexão com suspeitos desaparecidos. Em dentes naturais a fluorescência ocorre em dentina e também em esmalte, embora este apresente menor índice de fluorescência. É sabido que o esmalte, a dentina e polpa sofrem mudanças notáveis durante a vida do indivíduo. O esmalte torna-se mais mineralizado, liso e fino, sofre desgaste fisiológico e patológico o que pode causar áreas de exposição da dentina que altera a expressão cromática do dente natural. A polpa diminui em volume devido à deposição de dentina secundária, assim a dentina torna-se espessa com o tempo. Sendo o esmalte e a dentina responsáveis pelo fenômeno de fluorescência dental e estes elementos dentários sofrem alteração significativa durante a vida, sugere-se avaliar tal fenômeno sob a luz da odontologia legal com vista a desenvolver um método para se estimar a idade de um indivíduo. O presente estudo tem por propósito verificar a existência de correlação entre idade e alteração da fluorescência em dentes in vivo. A amostra foi constituída por 66 brasileiros, de ambos os gêneros, selecionados aleatoriamente. Os sujeitos de pesquisa se encontravam com idades entre 07 e 63 anos e foram divididos em 6 grupos: Grupo 1 07 a 12 anos; Grupo 2 - 13 a 20 anos; Grupo 3 21 a 30 anos; Grupo 4 31 a 40 anos; Grupo 5 41 a 50 anos e Grupo 6 51 a 63 anos. Foram incluídos na amostra os incisivos centrais superiores direito ou esquerdo livres de restaurações ou qualquer outro procedimento reabilitador ou estético nas regiões onde foi mensurada a fluorescência. Foi confeccionado um sistema de captura de imagem. A mensuração da fluorescência do dente foi realizada através da análise computacional das imagens digitais com o auxílio do software ScanWhite DMC / Darwin Systems - Brasil. A fluorescência dental decresce quando comparamos os grupos de faixa etária 21 a 30, 31 a 40, 41 a 50 e 51 a 63 anos, havendo diferença estatisticamente 8 significativa entre os grupos 41 a 50 anos e 21 a 30 anos (p=0,005) e também entre o grupo 51 a 63 anos e os demais grupos (p<0,05)). Pode-se concluir que a fluorescência dental está correlacionada com a idade e apresenta um comportamento semelhante e estável dos 7 aos 20 anos de idade, atinge seu valor máximo esperado na idade de 26,5 anos e a partir de então decresce. Através da análise do conjunto das variáveis estudas sugere-se tabela para auxiliar na identificação humana (Apêndice B). / In cases of identification of bones, some segments of the skeleton or isolated bones fetch the diagnostic data Biotype as an estimated age of the individual providing the possibility of establishing a connection to suspects disappeared. The fluorescence in natural teeth occurs in dentin and enamel as well, although this presents a lower rate of fluorescence. It is known that the enamel, dentin and pulp undergo remarkable changes during the life of the individual. The enamel becomes more mineralized, smooth and thin, wears physiological and pathological which can cause areas of dentine exposure that alters the expression of the natural tooth color. The pulp volume decreases due to deposition of secondary dentin as the dentin becomes thicker with time. Therefore, if the enamel and dentin are responsible for the phenomenon of fluorescence dental and these dental elements suffer significant changes during life, now the phenomenon of fluorescence is investigated appropriately can provide us a method to estimate the age of an individual. The purpose of this study was to verify the correlation between age and change in dental fluorescence in vivo. The sample consists of 66 Brazilians, both gender, randomly selected. Research subjects should be aged between 13 and 63 years and will be divided into five groups: Group 1 - ages 07 - 12 years, Group 2 - ages 13-20 years, Group 3 - ages 21-30 years, Group 4 - ages 31 to 40 years and Group 5 - aged 41- 50 years and Group 6: aged 51-63 years. The upper central incisors right or left will be examined and shall be free of restorations or other rehabilitative or cosmetic procedure, which includes whitening teeth, cheeks where it will be measured fluorescence. Were included in the sample the upper central incisors right or left free of any restoration or rehabilitation or aesthetic procedure in the regions where the fluorescence was measured. A system of image capture was fabricated. The measurement of the fluorescence of the tooth was performed by computer analysis of digital images with the help of software ScanWhite DMC / Darwin Systems - Brazil. 10 The fluorescence decreases when comparing dental age groups 21-30,31-40,41-50 and 51-63 years, statistically significant difference between the groups 41-50 years and 21-30 years (p=0.005) and also between the group 51-63 years and the other groups (p<0.05). It can be concluded that the dental fluorescence correlates with the age and has a similar and stable behavior at the 7 to 20 years of age, reaches its maximum expected value of 26.5 years of age and thereafter decreases. Through the analysis of all variables studied suggest table to assist in human identification (Appendix B).
10

Estimativa de ingestão do corante artificial amarelo crepúsculo e quantificação em alimentos consumidos pela população brasileira

Feitosa, Luana Carolina Alves January 2016 (has links)
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.

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