In plants, adenine nucleotides are essential for nucleic acid synthesis, as cofactors for biochemical reactions, and as precursors for the biosynthesis of the phytohormone cytokinin. Adenine nucleotides, such as AMP, are synthesized by the de novo synthesis pathway involving 10 sequential enzymatic reactions and 7 ATP/GTP molecules, and by the less energy-demanding salvage reactions. The enzymes catalyzing the latter route collectively make up the purine salvage pathway. The predominant enzyme in purine salvage is adenine phosphoribosyltransferase (APT), which catalyzes the one-step conversion of adenine to AMP. Plant APTs are also thought to contribute to the metabolism of cytokinins by interconverting the physiologically active base forms into their inactive nucleotide forms. In Arabidopsis thaliana APT is encoded by a five-member gene family, where APT1 contributes 99% of the APT activity. The APT1 gene has a six-exon gene structure that is present in APT genes of other organisms. Recently, expressed sequence tag (EST) collections have shown that the APT1 locus gives rise to a second, longer transcript variant that contains an additional 5?? terminal exon. For the purposes of this research the longer isoform has been designated APT1.1 and the shorter version, APT1.2. The aim of the first part of my thesis research was to determine the functional significance of these two transcript variants. Semi-quantitative RT-PCR showed that APT1.1 and APT1.2 transcripts are equally abundant in leaf and floral organs. However, immunoblot analysis revealed that APT1.2 is constitutively expressed, while APT1.1 is subject to post-transcriptional regulation in both organs. Using recombinant APT1.1 protein, preliminary enzymatic assays showed this protein to be very active on adenine substrates. Transgenic lines were constructed that either constitutively expressed the APT1.1 ORF fused to GFP protein, or that only expressed an Exon 1-GFP fusion protein from the native APT1 promoter. In both plant lines GFP localization was observed in stationary punctate bodies in mesophyll cells, whereas constitutive expression of the APT1.1 ORF also showed co-localization of GFP with chlorophyll autofluorescence. Although the identity of these punctate-bodies is currently inconclusive, preliminary data using transmission electron microscopy show that these bodies may be localized in areas of the chloroplast devoid of chlorophyll. Finally, bioinformatic analysis of available plant ESTs predicts that many other plants species may contain a similar gene structure to APT1 of Arabidopsis that gives rise to a cytosolic APT, and a chloroplast-localized APT. Interestingly, the only phenotype previously identified as arising from APT1-deficiency was aborted pollen development in a point mutant annotated as apt1-3. Recently, a novel APT1-deficient mutant was recovered during a screen for mutants that were tolerant to chemically induced oxidative stress. The mutant, oxt1, contains a T-DNA insertion element between the first and second exon of APT1 and surprisingly is as fertile as WT. Thus, the second part of this research was to determine the basis of fertility in the oxt1 mutant. A genetic cross between these two mutants resulted in an F1 plant that is a developmental chimera of both mutants. The initial siliques on the plant were fertile like oxt1, whereas the later siliques on the plant were sterile like apt1-3. Measurements of adenine and cytokinin levels showed substantial alterations in these metabolite levels. Thus, these metabolites may be potential contributors to the diverse phenotypes observed in each mutant. The discovery and characterization of the unusual phenotype of oxt1apt1-3 hybrids will lead the way in providing a model system to study changes in metabolite levels that contribute to the shift from fertility to sterility.

Thesis--University of Pennsylvania. / "Reprint from the Journal of the Society of Oriental Research, vol. XIV, no. 4."

Asset pricing models have been of interest since their origin in modern finance. The Capital Asset Pricing Model is a widely used tool and is one of the early developed asset pricing models in modern finance. There are continual improvements of this model with the evident multifactor models of Fama and French (2015), Carhart (1997) and the South African two – factor arbitrage pricing models of Van Rensburg (2002) and Laird-Smith et al. (2016). This research empirically investigates the performance of eight-different multi-factor asset pricing models in describing average portfolio returns in the South African Johannesburg Stock Exchange. We find that the Carhart (1997) four factor model comprising of the market factor, size factor, value factor and the momentum factor is the most parsimonious model and thus better explains the average portfolio returns in the South African JSE. This model is an improvement of the Fama and French (1992) three factor model. Additionally, we investigate the performance of the two factor Asset Pricing Theory (APT) model of Laird-Smith et al. (2016) and Van Rensburg (2002) that consists of the South African Financial Index (SAFI) and the South African Resources Index (SARI). We observe that the model performs better than the traditional CAPM that is widely used in industry. Adding the SAFI and the SARI to the six-factor model results in an eight-factor model that has a significant improvement in explaining average returns. The results indicate that the market factor, the South African Financial Index and the South African Resources Index (SARI) poorly explain each other but their linear combination improves the eight-factor asset pricing model in explaining average portfolio returns in the South African market. The eight – factor model comprises of the market, size, value, investment, profitability, momentum factors and the two South African indices namely, the South African Financials Index (SAFI) and the South African Resources Index (SARI).

The project elaborated in frame of engineering studies, solves the problem of restoration of the damaged hinge groove blades, and the surfacing of cylindrical faces of the SAW method, using additional material TOPCORE 838 B. The turbine rotor is made from steel with high resistance temperature 30CrMoNiV5-11. Based on literature studies and issues surfacing calculation, it was established that will preheat the material. The issue was solved by using simulation program SYSWELD.

As técnicas utilizadas pelas empresas atualmente para a avaliação econômica dos projetos de investimento em condições de risco, com destaque para a análise de cenários, apresentam três importantes limitações: não fornecem o capital no risco, utilizam uma taxa mínima da atratividade (TMA) única para a empresa em seu todo, desprezando as particularidades de cada caso, e tratam o risco isoladamente, fora do contexto amplo da diversificação eficiente. Diante desse contexto, o presente estudo propôs a aplicação de três modelos originários do mercado de capitais: o valor no risco (VAR), o modelo de precificação dos ativos de capital (CAPM) e a teoria de precificação por arbitragem (APT). Os resultados obtidos mostram que tais modelos são capazes de: fornecer o capital no risco dos projetos de investimento (VAR), utilizar uma TMA própria, segundo as particularidades de cada projeto de investimento (CAPM e APT), e tratar o risco em projetos de investimento no contexto amplo da diversificação eficiente (VAR, CAPM e APT). / The techniques used now by the companies for the economic evaluation of the investment projects in risk conditions, with prominence for the analysis of sceneries, present three important limitations: they don\'t supply the capital in the risk, they use an attractiveness of minimum rate (TMA) only for the company in its whole, despising the particularities of each case, and they treat the risk separately, out of the wide context of the efficient diversification. Before of that context, the present study proposed the application of three original models of the market of capitais: the value at risk (VAR), the capital asset pricing model (CAPM) and the arbitrage pricing theory (APT). The obtained results showed that such models are capable of: to supply the capital in the risk of the investment projects (VAR), to use an own TMA, according to the particularities of each investment project (CAPM and APT), and to treat the risk in investment projects in the wide context of the efficient diversification (VAR, CAPM and APT).

<p>I denna uppsats<strong> </strong>undersöker jag huruvida CAPM eller APT modellerna ger resultat på den svenska aktiemarknaden mellan 1998 och 2007. Jag undersöker om någon av dessa modeller passar in i den svenska aktiemarknaden och hurdan är resultatet. Det som gör uppsatsen intressant är att jag använder båda modellerna i en och samma studie och jämför resultatet av uppskattningar av modellerna. Som markandsindex har jag använt OMXS30 index och som makroekonomiska variabler i APT-modellen har jag använt inflation, oljepris, industriproduktionsindex och ränta. Resultatet av studien är att med de makroekonomiska variablerna, som jag har använt, ger både CAPM och APT likvärdiga resultat. Slutsatsen av min studie är att APT med de rätta variablerna är en bättre modell att skatta priset på aktier än CAPM.</p> / <p>In this essay, I examine whether CAPM or APT models give results on the Swedish stock market between 1998 and 2007. I examine if either CAMP or APT or both of these models fits in on the Swedish stock market and what the result is. What makes this essay interesting is that I use both models in one and the same study and compare the result of my estimates with these two models. As market index, I have used the OMXS30 index and as macroeconomic variables in APT model, I have used inflation, oil price, industry production index and interest. The result of the study is that with the macroeconomic variables, that I have used with APT and CAPM, gives CAPM and APT equivalent results. The conclusion of the study is that APT, with the correct variables, is better model for estimating the stock prices than CAPM.</p>

I denna uppsats undersöker jag huruvida CAPM eller APT modellerna ger resultat på den svenska aktiemarknaden mellan 1998 och 2007. Jag undersöker om någon av dessa modeller passar in i den svenska aktiemarknaden och hurdan är resultatet. Det som gör uppsatsen intressant är att jag använder båda modellerna i en och samma studie och jämför resultatet av uppskattningar av modellerna. Som markandsindex har jag använt OMXS30 index och som makroekonomiska variabler i APT-modellen har jag använt inflation, oljepris, industriproduktionsindex och ränta. Resultatet av studien är att med de makroekonomiska variablerna, som jag har använt, ger både CAPM och APT likvärdiga resultat. Slutsatsen av min studie är att APT med de rätta variablerna är en bättre modell att skatta priset på aktier än CAPM. / In this essay, I examine whether CAPM or APT models give results on the Swedish stock market between 1998 and 2007. I examine if either CAMP or APT or both of these models fits in on the Swedish stock market and what the result is. What makes this essay interesting is that I use both models in one and the same study and compare the result of my estimates with these two models. As market index, I have used the OMXS30 index and as macroeconomic variables in APT model, I have used inflation, oil price, industry production index and interest. The result of the study is that with the macroeconomic variables, that I have used with APT and CAPM, gives CAPM and APT equivalent results. The conclusion of the study is that APT, with the correct variables, is better model for estimating the stock prices than CAPM.

[pt] Este trabalho objetivou realizar um estudo de caso para analisar a performance da ação da Lojas Americanas (LAME 4), negociada na BMeFBOVESPA, utilizando quatro modelos de previsão de retornos esperados. Os modelos escolhidos foram: CAPM (Capital Asset Pricing Model) de Sharpe (1964), Lintner (1965) e Mossin (1966), modelo de 3 fatores de Fama e French (1992), modelo de 4 fatores de Fama, French e Carhart (1997) e o modelo APT (Arbitrage Pricing Theory) de Ross (1996). A metodologia foi estruturada em duas partes: utilização de regressões múltiplas para verificar a significância dos fatores em cada modelo e comparação dos resultados para indicar aquele que se mostrou mais adequado para explicar o comportamento do ativo. Por fim, o modelo de três fatores de Fama, French revelou-se mais apropriado. / [en] The objective of this study was to conduct a case study to analyze the performance of the Lojas Americanas stock (LAME 4), traded on the BMeFBOVESPA, using four expected returns prediction models. The chosen models were CAPM (Capital Asset Pricing Model) of Sharpe (1964), Lintner (1965) and Mossin (1966), model of 3 factors of Fama and French (1992), model of 4 factors of Fama, French and Carhart (1997) and the APT (Arbitrage Pricing Theory) model of Ross (1996). The methodology was structured in two parts: the use of multiple regressions to verify the significance of the factors in each model and the comparison of the results to indicate the one that was more adequate to explain the behavior of the asset. Finally, the three-factor model of Fama, French was found to be more appropriate.

As técnicas utilizadas pelas empresas atualmente para a avaliação econômica dos projetos de investimento em condições de risco, com destaque para a análise de cenários, apresentam três importantes limitações: não fornecem o capital no risco, utilizam uma taxa mínima da atratividade (TMA) única para a empresa em seu todo, desprezando as particularidades de cada caso, e tratam o risco isoladamente, fora do contexto amplo da diversificação eficiente. Diante desse contexto, o presente estudo propôs a aplicação de três modelos originários do mercado de capitais: o valor no risco (VAR), o modelo de precificação dos ativos de capital (CAPM) e a teoria de precificação por arbitragem (APT). Os resultados obtidos mostram que tais modelos são capazes de: fornecer o capital no risco dos projetos de investimento (VAR), utilizar uma TMA própria, segundo as particularidades de cada projeto de investimento (CAPM e APT), e tratar o risco em projetos de investimento no contexto amplo da diversificação eficiente (VAR, CAPM e APT). / The techniques used now by the companies for the economic evaluation of the investment projects in risk conditions, with prominence for the analysis of sceneries, present three important limitations: they don\'t supply the capital in the risk, they use an attractiveness of minimum rate (TMA) only for the company in its whole, despising the particularities of each case, and they treat the risk separately, out of the wide context of the efficient diversification. Before of that context, the present study proposed the application of three original models of the market of capitais: the value at risk (VAR), the capital asset pricing model (CAPM) and the arbitrage pricing theory (APT). The obtained results showed that such models are capable of: to supply the capital in the risk of the investment projects (VAR), to use an own TMA, according to the particularities of each investment project (CAPM and APT), and to treat the risk in investment projects in the wide context of the efficient diversification (VAR, CAPM and APT).

nÃo hà / Esta pesquisa foi realizada visando avaliar o desempenho de oito empresas do setor de construÃÃo civil, atravÃs da anÃlise do comportamento do retorno do preÃo de suas aÃÃes para o perÃodo de agosto de 2007 a setembro de 2014, considerando o impacto da crise financeira mundial, utilizando as metodologias APT (capital asset pricing model) e o modelo de mÃltiplos de mercado. Os resultados verificados indicaram que o desempenho das empresas refletiram os efeitos da crise financeira de 2008 e que as metodologias selecionadas puderam demonstrar efetivamente estes fatos com evidÃncias em seus resultados. / This research was conducted to evaluate the performance of eight companies in the construction sector, by analyzing the behavior of return on its stock price for the period from August 2007 to September 2014, considering the impact of the global financial crisis, using APT (capital asset pricing model) methodologies and the model of market multiples. The observed results indicate that the performance of businesses reflected the effects of the financial crisis of 2008 and selected methodologies can they effectively demonstrate these facts with evidence in their results.