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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.
41

Determinants of the Economic Growth in Mexico : An Exogenous Growth Model

Castro, José Luis January 2008 (has links)
<p> </p><p> </p><p>This bachelor thesis aims to uncover the determinants of the economic growth in Mexico with an exogenous growth model. The study is based in an Augmented Solow Model em-ployed by Mankiw, Romer and Weil in</p><p><em>"A contribution to the Empirics of the Economic Growth" </em>(1992). The model uses annual data of Mexico from 1960-2007 and the regressions and tests are developed in the econometric package Stata 10 for eight different periods. The thesis not only uses the Effective Labour and Physical Capital as Inputs in the production Function, but also employs the variable of Human Capital as an economic determinant of growth in the production function. The results of the model correspond with the actual scenario in Mexico; more weight to the Effective Labour (76.34%) rather than to Human Capital (2.12%) or Physical Capital (21.54%) as determinants of growth.</p><p> </p><p> </p>
42

Pricing and competition in the Swedish retail market for electricity

Lu, Yuhao January 2015 (has links)
Sweden, together with Norway, Finland and Denmark, have created a multi-national electricity market called NordPool. In this market, producers and retailers of electricity can buy and sell electricity, and the retailers then offers this electricity to end consumers such as households and industries. Previous studies have shown that pricing at the NordPool market is functioning quite well, but no other study has to my knowledge studied if pricing in the retail market to consumers in Sweden is well functioning. If the market is well functioning, with competition and low transaction costs when changing electricity retailer, we would expect that a homogeneous good such as electricity would be sold at the approximately same price, and that price changes would be highly correlated, in this market. Thus, the aim of this study is to test whether the price of Vattenfall, the largest energy firm in the Swedish market, is highly correlated to the price of other firms in the Swedish retail market for electricity. Descriptive statistics indicate that the price offered by Vattenfall is quite similar to the price of other firms in the market. In addition, regression analysis show that the correlation between the price of Vattenfall and other firms is as high as 0.98.
43

Egzogeninės abscizo rūgšties poveikis Setaria viridis (L.) P. Beauv. morfofiziologiniams parametrams / Effect of exogenous abscisic acid on Setaria viridis (L.) P. Beauv. morphophysiological parameters

Galginaitis, Justas 21 June 2013 (has links)
Magistrantūros studijų pateikiami egzogeninės abscizo rūgšties poveikis Setaria viridis (L.) P. Beauv. morfofiziologiniams parametrams tyrimų rezultatai. Darbo objektas – žalioji šerytė (Setaria viridis (L.) P. Beauv.). Darbo metodai: IV organogenezės tarpsnyje žaliosios šerytės augalai nupurkšti abscizo rūgšties tirpalais ir auginti programuojamoje auginimo kameroje esant 20/18 °C (diena/naktis) temperatūrai, 16/8 val. (diena/naktis) fotoperiodui, 50 µmol m-2 s-1 apšviestumui. Fotosintezės pigmentai, augalo žalia masė ir sausos medžiagos kiekis nustatyti praėjus 1, 5, 10 ir 15 dienų po purškimo. Esant 35-40% substrato drėgniui augalai nupurkšti 0,5 µM abscizo rūgšties tirpalu ir toliau auginti programuojamoje auginimo kameroje sausros sąlygomis. Fotosintezės pigmentai, augalo žalia masė ir sausos medžiagos kiekis nustatyti po 3 ir 6 sausros dienų. Darbo rezultatai. Visos tirtos egzogeninės abscizo rūgšties koncentracijos slopino chlorofilo a sintezę žaliosios šerytės augaluose, tuo tarpu chlorofilo b kiekis žaliosios šerytės augaluose priklausė nuo ABR koncentracijos ir auginimo trukmės po purškimo. Karotenoidų kiekis žaliosios šerytės augaluose statistiškai patikimai didėjo egzogeninės absciso rūgšties poveikyje. Egzogeninė abscizo rūgštis esmingai mažino tirtų augalų žalią masę. Statistiškai patikimai didesnis nei kontroliniame variante sausos medžiagos kiekis nustatytas tik nupurškus augalus 1,5 µM ABR koncentracija po 15 auginimo dienų. Egzogeninė abscizo rūgštis mažino... [toliau žr. visą tekstą] / The objective of this study was to investigate the effect of exogenous abscisic acid on morphophysiological parameters of green millet plants. Object of the work – green millet (Setaria viridis (L.) P. Beauv.). Methods of the work: green millet plants were to spray with abscisic acid and growing in growth chamber under 20/18 °C (day/night) temperature, 16/8 h (day/night) photoperiod, 50 µmol m-2 s-1 light intensity. Amount of photosynthetic pigments, fresh mass of plants, dry weight after was evaluated 1, 5, 10 and 15 days after treatment. When substrate humidity was 35-40%, plants were to spray with 0.5 M abscisic acid and growing in growth chamber under moisture deficit. The results of work. All tested concentrations of abscisic acids inhibited chlorophyll a synthesis in green millet plant, while amounts of chlorophyll b were dependent on concentration of abscisic acid. The carotenoids content in green millet plants were significantly increased under treatment of exogenous abscisic acid, while the fresh mass of plants significantly decreased. Significantly higher dry weight in comparison with control has been obtained under influence of 1.5 M ABA after 15 growing days. Exogenous abscisic acid decreased chlorophylls content in plants treated by drought stress. Growing green millet plants under moisture deficit, exogenous ABA didn’t shown any influence on fresh mass and dry weight.
44

The influence of hypotonic carbohydrate electrolyte solutions on muscle metabolism and exercise capacity with regards to intermittent high intensity shuttle running

Foskett, Andrew January 2003 (has links)
Performance and exercise capacity in prolonged continuous exercise has been shown to be enhanced by the ingestion of dilute (-6%) carbohydrate-electrolyte (CHO-E) solutions during exercise. There is a wealth of literature on the effects of CHO-E solutions on prolonged, continuous exercise however this is not the case for highintensity intermittent exercise. One reason for this is the difficulty of replicating the demands of multiple-sprint sports within the laboratory. The development of the Loughborough Intermittent Shuttle Running Test (LIST), a protocol that simulates the physiological demand of multiple-sprint sports, has allowed for further study in this area. Sports drinks contain a variety of different types of carbohydrate, including synthetic polymers of maltodextrins. The rationale for these is two-fold; firstly there is some evidence to suggest that these glucose polymers of low osmolality may empty faster than isoenergetic glucose solutions especially at dilute (-6%) concentrations. Secondly CHO-E solutions formulated from maltodextrins with low dextrose equivalents are less acidogenic and have lower cariogenic potential than simple glucose solutions, thus making them preferable for tooth health. Therefore the purpose of this thesis was to examine the effects of a 6.4% hypotonic synthetic polymer maltodextrin CHO-E solution on muscle metabolism and physiological performance during prolonged high-intensity intermittent running (LIST). This thesis contains four experimental studies. From the results of study 1 it was concluded that the ingestion of a 6.4% hypotonic CHO-E solution provided no ergogenic benefit to running capacity during the LIST despite blood and hormonal data suggesting that the solution was effective at delivering glucose. As isotonic CHO-E solutions have shown to have ergogenic properties during LIST running the purpose of study 2 was to compare isoenergetic hypotonic and isotonic CHO-E solutions during LIST running. The results from this study suggested that performance, as measured by exercise capacity and sprint speed, was not affected by either treatment. In study 3 the protocol was modified to extend the exercise duration so that a greater demand was placed on the subjects' glycogen reserves. The results from this study further confirmed that exercise capacity in LIST running was not influenced by CHO provision during exercise however the habitual CHO intake of the subjects may have masked any ergogenic properties of the CHO-E solution and led to increased performance in the control trials. In the final study the subjects' pre-trial exercise and dietary CHO intake was manipulated to increase endogenous glycogen concentrations. The results showed that in these subjects the ingestion of a 6.4% hypotonic CHO-E solution increased exercise capacity during the LIST by 21%. Muscle biopsy analyses revealed a lower net muscle glycogen utilisation in the CHO trial post-90 min (p=0.07). There is evidence in the literature to suggest that there is an ergogenic effect of CHO ingestion during the LIST. However the results presented in this thesis suggest that when endogenous glycogen stores are moderate the ingestion of a CHO-E solution may suppress lipid oxidation without a concomitant increase in CHO oxidation and thus LIST capacity is not enhanced. In contrast, when endogenous glycogen concentrations are elevated through dietary manipulation there is an ergogenic benefit from the ingestion of hypotonic CHO-E solutions during LIST exercise.
45

Farinha de penas e protease em dietas para codornas de corte

Diana, Thiago Ferreira 26 July 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-04-06T18:56:26Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thiago_ferreira_diana.pdf: 858858 bytes, checksum: 5152a8b8e2af6ccba2e79bc8c5a4599b (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-04-09T19:15:56Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thiago_ferreira_diana.pdf: 858858 bytes, checksum: 5152a8b8e2af6ccba2e79bc8c5a4599b (MD5) / Made available in DSpace on 2018-04-09T19:15:56Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thiago_ferreira_diana.pdf: 858858 bytes, checksum: 5152a8b8e2af6ccba2e79bc8c5a4599b (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Objetivou-se com este trabalho avaliar o desempenho de codornas de corte alimentadas com farinha de penas e protease nas dietas durante as fases de oito a 21 e de oito a 35 dias de idade. A an?lise dos dados seguiram a seguinte forma: primeiro utilizou-se 360 codornas distribuidas em delineamento inteiramente casualizado (DIC), totalizando em nove tratamentos, quatro repeti??es de 10 aves por parcela. Os tratamentos experimentais foram: T1: Controle positivo (CP) + 0% farinha de penas (FP); T2: CP + 5% FP; T3: CP + 10% FP; T4: Controle negativo (CN), com redu??o de 8% proteina bruta (PB) e amino?cidos em rela??o ao CP + 0% FP; T5: CN + 5% FP; T6: CN + 10% FP; T7: CN + 0% FP + protease; T8: CN + 5% FP + protease e T9: CN + 10% FP + protease. Para o segundo utilizou-se 240 codornas distribu?das em DIC, em esquema fatorial 2 x 3 (duas dietas (CP e CN) x tr?s n?veis de farinha de penas (FP)), totalizando em seis tratamentos, quatro repeti??es de 10 aves por parcela. Os tratamentos experimentais foram: T1: CP + 0% FP; T2: CP + 5% FP; T3: CP + 10% FP; T4: CN + 0% FP; T5: CN + 5% FP e T6: CN + 10% FP. E para o terceiro utilizou-se 240 codornas distribu?das em DIC, em esquema fatorial 2 x 3 (duas inclus?es da enzima (com e sem) x 3 n?veis de FP), totalizando em seis tratamentos, quatro repeti??es de 10 aves por parcela. Os tratamentos experimentais foram: T1: Ra??o reduzida (RD) em 8% da exig?ncia de PB e amino?cidos + 0% FP; T2: RD + 5% FP; T3: RD + 10% FP; T4: RD + 0% FP + protease; T5: RD + 5% FP + protease e T6: RD + 10% FP + protease. As vari?veis de desempenho avaliadas foram: o consumo de ra??o, o ganho de peso e a convers?o alimentar. Aos 35 dias de idade avaliou-se o peso vivo e o rendimento de carca?a, de cortes nobres (peito e coxa+sobrecoxa) e an?lise de rentabilidade econ?mica. As inclus?es crescentes da FP nas ra??es ocasiona redu??o do desempenho das codornas nas duas fases em estudo, entretanto, pode ser utilizada nas ra??es em 5% sem preju?zo ao desempenho. A utiliza??o da enzima protease (caracter?stica de serina) n?o proporciona melhoria no desempenho das aves e n?o contrubui para melhor digest?o da FP, havendo necessidade de estudos utilizando a enzima queratinase. A protease adicionada em ra??es com redu??o de PB e amino?cidos, contendo FP n?o melhora o desempenho das aves. Ra??es reduzidas em PB e amino?cidos n?o apresenta-se como boa estrat?gia para melhorar o desempenho das codornas. A an?lise de rentabilidade econ?mica revela que ra??es controle positivo com 0 e 5% de FP apresentam melhor ?ndice. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The objective of this study was to evaluate the performance of meat-type quail fed with feather meal and protease in the diets during the phases of the eight to 21 days and eight to 35 days of age. Data were analyzed as follows: firstly, 360 quails distributed in a completely randomized design (CRD) were used with a total of nine treatments, four replicates of 10 birds per plot. The experimental treatments were: T1: Positive control (PC) + 0% feather meal (FM); T2: PC + 5% FM; T3: PC + 10% FM; T4: Negative control (NC), with reduction of 8% crude protein (CP) and amino acids in relation to PC + 0% FM; T5: NC + 5% FM; T6: NC + 10% FM; T7: CN + 0% FM + protease; T8: NC + 5% FM + protease and T9: NC + 10% FM + protease. For the second, 240 quails distributed in CRD were used, in a 2 x 3 factorial scheme (two diets (CP and NC) x three levels of feather meal (FM)) with a total of six treatments, four replicates of 10 birds per plot. The experimental treatments were: T1: CP + 0% FM; T2: CP + 5% FM; T3: CP + 10% FM; T4: CN + 0% FM; T5: CN + 5% FM and T6: CN + 10% FM. Finally, for the third experiment, 240 quails distributed in CRD were used, in a 2 x 3 factorial scheme (two enzyme inclusions (with and without) x three FM levels) with a total of six treatments, four replicates of 10 birds per plot. The experimental treatments were: T1: Reduced ration (RD) in 8% of the requirement of CP and amino acids + 0% FM; T2: RD + 5% FM; T3: RD + 10% FM; T4: RD + 0% FM + protease; T5: RD + 5% FM + protease and T6: RD + 10% FM + protease. The performance variables evaluated were: feed intake, weight gain and feed conversion. At 35 days of age, live weight and carcass yield were evaluated, from noble cuts (breast and thigh + drumstick), and analysis of economic profitability. Increasing inclusion of FM in feed causes a reduction in the performance of quails in the two phases under study, however, it can be used in rations in 5% without compromising performance. The use of the protease enzyme (serine characteristic) does not improve the performance of the birds and does not contribute to a better digestion of FM, requiring studies using the enzyme keratinase. Protease added in diets with reduced CP and amino acids, containing FM does not improve poultry performance. Reduced CP and amino acid rations do not present as a good strategy to improve quail performance. The economic profitability analysis reveals that positive control rations with 0 and 5% PF present a better index.
46

Endogenous and Exogenous Instrumentality on Student Motivation and Achievement

January 2016 (has links)
abstract: Instrumentality is an important motivational construct that empathizes the connection between a present task and a future goal. Instrumentality is conceptualized as a task-specific variable. Reflecting context-dependent characteristics, two different types of instrumentality are distinguished: endogenous and exogenous instrumentality. Endogenous instrumentality is the perception that learning in a present task is useful to achieving valued future goals and exogenous instrumentality is the perception that outcome in a present task is instrumental to achieving valued future goals. This study investigated the differential relationships among each instrumentality type, academic achievements, and motivational variables. Three studies were conducted to investigate the relationship between each type of instrumentality and students’ achievement and motivational variables such as achievement goals, situational interests, and pressure and the moderating role of self-efficacy on the relationship. Study 1 investigated how endogenous and exogenous instrumentality was related to students’ achievement respectively. In addition, it was examined whether self-efficacy moderated in the relationship between each instrumentality and achievement. Study 2 was conducted to find that how each instrumentality was related to three different types of achievement goals, which were mastery, performance-approach, and performance-avoidance goals. Interaction between each type of instrumentality and self-efficacy was examined to find a moderating effect by self-efficacy on accounting for the relationship between instrumentality and achievement goals. Study 3 examined the role of each instrumentality on situational interest, pressure and achievement. The results showed that endogenous instrumentality predicted grade positively regardless students’ self-efficacy level, whereas exogenous instrumentality positively predicted grade of students with high self-efficacy and negatively predicted grade of students with low-self-efficacy. In addition, endogenous instrumentality predicted mastery goals positively and performance-avoidance goals negatively, whereas exogenous instrumentality predicted both performance-approach and performance avoidance goals positively. Moreover, students with high self-efficacy were less likely to adopt performance-avoidance goals when they perceived more endogenous instrumentality. It was also found that endogenous instrumentality was a positive predictor of situational interest and a negative predictor of pressure, whereas exogenous instrumentality was a negative predictor of situational interest and as a positive predictor of pressure. There was a mediating effect of pressure on the relationship between each instrumentality and grade. / Dissertation/Thesis / Doctoral Dissertation Educational Psychology 2016
47

Connecting to the Future: A Revised Measure of Exogenous Perceptions of Instrumentality

January 2017 (has links)
abstract: The primary objective of this study was to revise a measure of exogenous instrumentality, part of a larger scale known as the Perceptions of Instrumentality Scale (Husman, Derryberry, Crowson, & Lomax, 2004) used to measure future oriented student value for course content. Study 1 piloted the revised items, explored the factor structure, and provided initial evidence for the reliability and validity of the revised scale. Study 2 provided additional reliability evidence but a factor analysis with the original and revised scale items revealed that the revised scale was measuring a distinct and separate construct that was not exogenous instrumentality. Here this new construct is called extrinsic instrumentality for grade. This study revealed that those that endorse a high utility value for grade report lower levels of connectedness (Husman & Shell, 2008) and significantly less use of knowledge building strategies (Shell, et al., 2005). These findings suggest that there are additional types of future oriented extrinsic motivation that should be considered when constructing interventions for students, specifically non-major students. This study also provided additional evidence that there are types of extrinsic motivation that are adaptive and have positive relationships with knowledge building strategies and connectedness to the future. Implications for the measurement of future time perspective (FTP) and its relationship to these three proximal, future oriented, course specific measures of value are also discussed. / Dissertation/Thesis / Doctoral Dissertation Family and Human Development 2017
48

Altas doses de 6-fitase de origem híbrida para frangos de corte de 1 a 41 dias / High doses of 6 phytase of hybrid origin for broilers from 1 to 41 days

Ana Paula de Oliveira Saccomani 27 September 2018 (has links)
Objetivou-se elaborar uma revisão sistemática da literatura das exigências de cálcio e fósforo com o uso da enzima fitase em ração para frangos de corte e avaliar altas doses de 6-fitase híbrida em rações, com ajuste na matriz nutricional, sobre o desempenho produtivo, aspectos econômicos, qualidade óssea e características de carcaça de frangos de corte. Para a revisão sistemática adotou-se a metodologia proposta por Lovatto et al. (2007), com a localização de artigos relacionados com o tema, coleta de dados, análise crítica dos artigos, interpretação e representação dos resultados encontrados. Para o desempenho, conduziu-se um experimento com 1200 pintos de um dia, Cobb500®, com peso médio de 47,94 &plusmn; 0,54 g, distribuídos em um delineamento em blocos casualizados com cinco tratamentos, com oito repetições de 30 aves cada. Os tratamentos utilizados foram: 1) Controle positivo de acordo com as exigências da Tabela Brasileira para Aves e Suínos; 2) Controle negativo (CN) com redução na matriz nutricional equivalente a dose de fitase de 750 FTU/kg, mas sem a inclusão da enzima; 3) CN com inclusão da fitase em 750 FTU/kg; 4) CN com inclusão da fitase em 1000 FTU/kg; e 5) CN com inclusão da fitase em 1500 FTU/kg. A redução dos nutrientes no controle negativo foi de 0,184% de fósforo disponível, 84,8 kcal/kg de energia metabolizável, 0,36% de proteína bruta, 0,206% de cálcio, 0,002% de sódio, 0,006% de lisina digestível e 0,019% de metionina+cistina digestível. A enzima utilizada foi Natuphos® E 10.000 FTU/g, nova 6-fitase de origem híbrida. Para o desempenho e o rendimento de carcaça foram observadas diferenças entre os tratamentos (p&lt;0,05), sendo que o controle negativo gerou resultados inferiores em relação aos demais tratamentos, enquanto que, para a análise econômica gerou resultados inferiores para as receitas brutas e superiores para os custos de produção (p&lt;0,05). Para a qualidade óssea, a suplementação de fitase nos níveis de 1000 e 1500 FTU/kg geraram resultados semelhantes aos encontrados para o controle o positivo (p&lt;0,05). Dessa maneira, concluiu-se que a suplementação da 6-fitase híbrida em níveis de 1000 e 1500 FTU/kg, com redução de nutrientes na matriz nutricional, melhora o desempenho, as características de carcaça, os aspectos econômicos e os parâmetros de qualidade óssea, conseguindo alcançar a mesma qualidade óssea do controle positivo, porém com um custo reduzido. / The objective of this study was to systematically review the literature on calcium and phosphorus requirements with the use of phytase enzyme in broiler feed and evaluate the levels of hybrid 6-phytase in diets, with an adjustment in the nutritional matrix, on the productive performance, bone quality, and carcass characteristics of broiler chickens. For the systematic review, the methodology proposed by Lovatto et al. (2007), for the localization of articles related to the theme, data collection, critical analysis of the articles, interpretation and representation of the results found. For broilers from 1 to 21 days, the enzyme phytase Natuphos is the most studied and levels above 500 FTU / kg can be used without compromising the performance of the animals, in addition to significantly improving the cost of. An experiment was carried out with 1200 day-old Cobb500® chickens, with a mean weight of 47.94 &plusmn; 0.54 g, distributed in a randomized block design with five treatments, with eight replicates of 30 birds each. The treatments used were: 1) Positive control according to the requirements of the Brazilian Poultry and Pork Table; 2) Negative control (CN) with reduction in nutritional matrix equivalent to phytase dose of 750 FTU / kg, but without inclusion of the enzyme; 3) CN with phytase inclusion at 750 FTU / kg; 4) CN with phytase inclusion at 1000 FTU / kg; and 5) CN with phytase inclusion at 1500 FTU / kg. The nutrient reduction in the negative control was 0.184% of available phosphorus, 84.8 kcal / kg of metabolizable energy, 0.36% crude protein, 0.206% calcium, 0.002% sodium, 0.006% digestible lysine and 0.019 % digestible methionine + cystine. The enzyme used was Natuphos® E 10,000 FTU / g, a novel 6-phytase of hybrid origin. For carcass performance and yield, differences between treatments (p &lt;0.05) were observed, and the negative control generated lower results in relation to the other treatments, whereas, for the economic analysis, lower results were obtained for gross and production costs (p &lt;0.05). For bone quality, phytase supplementation at 1000 and 1500 FTU / kg levels were found to be similar to the positive control results (p &lt;0.05). Thus, it is concluded that supplementation of hybrid 6-phytase at levels of 1000 and 1500 FTU / kg, with nutrient reduction in the nutritional matrix, improves performance, carcass characteristics, economic aspects and parameters of bone quality, achieving the same quality bone of the positive control, but with a reduced cost.
49

Estudos sobre o relacionamento entre estrutura de capital e setor / Essays on the relationship between Capital Structure and Industry

Rossimar Laura Oliveira 05 September 2018 (has links)
Esta tese é composta por três artigos que exploram a relação entre estrutura de capital e o setor. A literatura traz evidências que as firmas consideram as ações e decisões de seus pares competidores para tomar suas próprias decisões e que dentro deste ambiente elas podem ter estruturas de capital homogêneas. O objetivo geral é encontrar evidências que fatores relacionados ao setor são relevantes na determinação da estrutura de capital das firmas brasileiras. A contribuição está na busca pelos motivos que explicam esta influência e se os padrões do setor são importantes para as empresas brasileiras, como têm se mostrado para dados de empresas americanas. Esta tese se justifica por contribuir diretamente com as pesquisas que buscam avançar na compreensão de como os fatores relacionados ao setor vão afetar a estrutura de capital das firmas, sem desconsiderar os fatores internos. O primeiro capítulo é um artigo teórico que revisa os artigos publicados sobre o papel do endividamento nas relações intrasetor, competição e Organização Industrial. A relação da alavancagem com desempenho e sobrevivência é um dos temas principais. Os estudos revisados mostram que muitas vezes a firma endividada vai ter pior desempenho no mercado devido ao comportamento predatório das rivais. Não há consenso sobre o comportamento da firma endividada, existem autores que acreditam no comportamento mais agressivo, outros no comportamento mais conservador, assim como a falência de uma firma no setor pode trazer resultados positivos ou negativos para as demais. O segundo capítulo é um artigo empírico que utiliza as alterações de IPI realizadas pelo governo brasileiro como choques exógenos na relação entre alavancagem da firma e do setor. Foram utilizados dados de empresas brasileiras entre 2007-2015. O modelo econométrico utilizado foi o diff-in-diff-in-diff. Os resultados mostram uma relação positiva entre a alavancagem média do setor e da firma, relação esta que se mantém para o grupo de tratamento após a inclusão do choque exógeno de redução do IPI no modelo. Estes resultados se alinham com trabalhos que colocam o setor no centro dos aspectos influenciadores da estrutura de capital da firma. O terceiro e último capítulo também é um artigo empírico onde, em um modelo de ajustamento parcial, a relação entre oportunidades de crescimento de uma firma, quando maiores que as oportunidades de crescimento do setor, vão representar possíveis choques exógenos idiossincráticos recebidos por ela. Foram utilizados dados de empresas brasileiras entre 1995-2016. Os resultados principais confirmam que existe uma relação negativa, se há aumento da razão das oportunidades de crescimento da firma i em relação às oportunidades de crescimento do seu setor j, seus indicadores de alavancagem serão reduzidos, se houver queda na razão das oportunidades de crescimento, haverá aumento da alavancagem. Estes resultados estão ligados a trabalhos que afirmam que empresas com maiores oportunidades de investimento são mais eficientes, tem maior lucratividade e vão procurar manter níveis mais baixos de alavancagem e à Teoria da Agência quando demonstra que as firmas com baixas oportunidades de investimento usam o aumento da dívida como forma de controle dos gerentes. / This doctoral dissertation is composed of three papers that explore the relationship between capital structure and the Industry. Literature brings evidence that firms consider the actions and decisions of their competing peers to make their own decisions and they may have homogenous capital structures. The primary objective is to find evidence that industry factors are relevant in determining the capital structure of Brazilian firms. The study contribution is clarifying the reasons for this influence and answering if the industry\'s standards are important for the Brazilian companies as they have been as shown for the data of American companies. This dissertation is justified by contributing to the researches that advance in the understanding of how the industry\'s factors will affect the capital structure of the firms, without disregarding the internal factors. The first chapter is a theoretical article that reviews papers about the role of debt in the intraindustry relations, competition and Industrial Organization. The relationship of leverage with performance and survival is one of the main themes. The reviewed studies show that often the indebted firm will poorly perform on the market due to the predatory behavior of rivals. There is no consensus about the behavior of the indebted firm, there are authors who believe in more others in less aggressive behavior, as well as the bankruptcy of one firm in the industry can bring positive or negative results to others. The second chapter is an empirical investigation that uses IPI benefits (tax benefit) offered by the Brazilian government as an exogenous shock in the relationship between firm and industry leverage. We used data from Brazilian companies between 2007 and 2015. The econometric model used was diff-in-diff-in-diff. The results show a direct relationship between the mean industry leverage and the firm\'s leverage. The same remains for the treatment group after inclusion of exogenous shock of IPI reduction in the model. These results are aligned with studies that consider the industry as the principal influencing aspect of the firm\'s capital structure. The third and final chapter is also an empirical investigation using a partial adjustment model. The relationship between a firm\'s growth opportunities, when larger than the industry\'s growth opportunities, will represent possible received idiosyncratic exogenous shock. The Data is from Brazilian companies between 1995 and 2016. The main results confirm that there is an inverse relationship. If the ratio of growth opportunities of firm i compared with the growth opportunities of its industry j increase, than its leverage indicators will be reduced. If there is a decrease in the growth opportunities, than there will be increased leverage. These results are related to papers that show companies with greater investment opportunities are more efficient, have higher profitability and will try to maintain lower levels of leverage. These results are also related to Agency Theory, when it demonstrates that firms with low investment opportunities use the increase debt as a managerial control tool.
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Assessment of a solid-state fermentation product in contemporary and lupin-containing diets for commercial finfish

Bowyer, Peter Hervé A. January 2016 (has links)
This body of research explores the dietary application of a bioactive, solid-state fermentation (SSF) product in contemporary and lupin-containing diets of Nile tilapia (Oreochromis niltoticus) and rainbow trout (Oncorhynchus mykiss). Consequently, the work provides holistic assessment of the influences of SSF products on animal health and performance; depending upon rearing temperature, nutritional physiologies, feed formulations and extrusion conditions; alongside information on the performance of lupins in aquafeeds. The SSF product (at 0.1 % inclusion) improved growth performance of Nile tilapia fed diets containing lupins. Phosphorous retention appeared higher when the SSF product was included in a yellow lupin (Lupinus luteus) diet whilst Mg retention was significantly higher in fish fed narrow-leaf lupin (Lupinus angustifolius). The experimental ingredients did not appear to show any clear effects upon midgut macrostructure. At an ultrastructural level, the fish fed yellow lupin alone, displayed poorest brush border characteristics but those fed yellow lupin and the SSF product showed signs of amelioration since they did not differ significantly from those fed narrow-leaf lupin. Focus was then turned towards a yellow lupin-based diet in rainbow trout, with two inclusion levels of the SSF product. The SSF product significantly improved growth performance and feed efficiency at 0.5 %, with values closer to a fishmeal-based diet than the lupin control. The SSF product increased the digestibility of protein and energy and bioavailability of numerous elements. However, the digestibility and bioavailability of certain nutrients, e.g. fibre and Zn, were only increased with a 0.5 % inclusion. The SSF product influenced vertebral Ca:P ratio but no effect on vertebral morphology was identified. Fish fed yellow lupin kernel meal displayed high Mn concentrations throughout a number of tissues. The intestinal environment was explored in depth, revealing large differences dependent upon SSF product inclusion rate. Fish fed a 0.1 % inclusion exhibited deteriorated brush border characteristics and high diversity of microbes, including increased proportions of key salmonid pathogens. Those fed a 0.5 % inclusion displayed signs of increased surface area at an ultrastructural level, reduced goblet cell numbers and a low microbial diversity; with domination of one particular family, Enterobacteriaceae. Activities of alkaline phosphatase and leucine aminopeptidase within the anterior intestine also appeared to be influenced by SSF product inclusion. Variations in haemato-immunological parameters were also observed between the treatments. In the final experiment, the SSF product was applied, pre-extrusion, to a contemporary rainbow trout formulation, at 0, 0.5, 1.0 and 1.5 %. No significant improvements to performance were identified following SSF product inclusion. However, crude protein digestibility from SSF-supplemented diets was significantly higher than the control and tendencies towards elevated retention of Ca, P, and Mg were apparent. In vitro analysis of free-phosphate release was conducted upon pre- and post-extruded diets, at varying temperatures. This indicated that neither extrusion conditions (105 °C) nor an ambient temperature of 10 °C were sufficient to cease P-liberating capabilities by the SSF product; suggesting that the two conditions combined limited the product’s efficacy in practice. This research evidenced that SSF products can be an effective means of improving the available nutrient profiles of compound diets for both omnivorous, warmwater and carnivorous, temperate finfish. Lupins are a promising alternative protein source but their nutritional value can be substantially improved by SSF product application. Exploration of the effects of SSF products on the intestinal environment revealed that both negative and positive effects on intestinal health can occur, which is highly dependent upon product inclusion rate. The holistic approaches adopted within this series of studies have seldom been performed on monogastric animals and thus provide valuable, transferable information for advancing knowledge in the application of SSF products, exogenous enzymes and lupins to farm animal feeds, in general.

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