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Since the Bretton Woods System collapsed, the volatility of the exchange rate return has been an important and concerned issue in financial domain. The purpose of this paper is to investigate the empirical relevance of stricture breaks for the volatility of the exchange rate return, and we use both in-sample and out-of-sample tests. GARCH(1,1) Model is considered to be the representative quantitative method for analyzing the volatility of asset returns, as a result, we picked GARCH(1,1) as natural benchmarks in this article. In addition, we cogitated the structure breaks in this paper, and used ICSS(Iterated Cumulative Sums of Squares) algorithm to test the points of structural breaks. The results of empirical analysis show that there are significant evidences of structural breaks in the unconditional variance for six of eight US exchange rate return series, which implying unstable GARCH processes for these exchange rates. We also find those competing models that accommodating structural breaks will have higher predictive ability. Pooling forecasts from different models that allow for structural breaks in volatility appears to offer a reliable method for improving volatility forecast accuracy given the uncertainty surrounding the timing and size of the structural breaks.

This dissertation includes two different empirical models about the economic growth and globalization in developed and developing countries from 1970 to 2008. First, we apply the quantile cointegration model provided by Xiao (2009) to examine the non-linear relationship between economic growth and globalization. Our empirical findings provide not only strong evidence that the cointegrating coefficients follow the time-varying process, but also the viewpoint of a long-run approach that overall globalization and their three dimensions act as engines of economic growth. Second, we adopt an advanced panel cointegration method which incorporates multiple structural breaks to examine the growth-globalization relationship. Differing from the weak outcomes of the traditional panel ointegration test without breaks, our findings provide strong evidence that overall globalization and its social dimension are cointegrated with RGDP both in developed and developing samples, and most of the structural break points are discovered in several main events. In addition, in evaluating whether or not the structural breaks affect the RGDP through globalization, we discover that the globalization have a directly positive impact on RGDP but indirectly exhibit negative (positive) impacts on real output via the channel of globalization in developed (developing) samples. Also, Different countries/groups reflect the different outcomes from the common shock of break event under the process of globalization. For the entire performance, the overall globalization brings the most positive effect on the real output in developed samples, and the social globalization is the main factor of promoting the economic development in developing samples.

In the early years of human society, all natural resources such as agriculture, animals, forestry, and fisheries were considered to be public property and the treasure belonged to all people. One branch of these natural resources threatened by over-development is straddling and highly migratory fish species, like tuna, which cannot be protected by a single government. While discussing fishery management, we review the change in tuna catches of thirteen countries in Western and Central Pacific Fisheries Commission (WCPFC), as it represents the impacts from different policies and events during a specific period of time. We reference the method applied in economics science by testing for the existence of stochastic convergence and addressing these break points, which are the important targets due to external shocks or internal influence. The characteristic of the method is in testing both time series and panel data by following the traditional unit root tests methods and unit root tests while considering structural breaks. We are able to conclude in preliminary estimates that some serious historical fishery events happened at the break point time, and if we take these structural breaks into consideration, then the growth of tuna catches will be stationary. In other words, if shocks to relative tuna catches are temporary, then the series stochastically converges, meaning that the manager does not need to intervene in the development of tuna fishery, because temporary shocks do not affect the stationarity of tuna catches¡¦ levels. Once the structural breaks occurred in the past, it is not necessary for these government and international organizations to change fishery policies in order to respond to the breaks. They should realize the meaning of the stationary panel instead of enacting an over-intervening policy based on temporary shocks.

In the literature, it is a common belief that the U.S. stock market is the single most influential market in the world. The U.S. stock market is a global factor, affecting both developed and emerging markets. This dissertation empirically investigates the interactions between equity markets of the Asian four little dragons (Hong Kong, Korea, Singapore, and Taiwan) and the U.S. equity market. In order to assess correctly the effect of the U.S. stock return rates on emerging equity markets, we incorporate the assumption that returns on the U.S. stock market affect the stock returns on emerging markets but not vice versa. In other words, it is assumed that the U.S. stock exchange performance is not affected by one of the four Asian equity market; however, the latter is affected by both its own dynamics and the U.S. stock exchange. This dissertation consists of three essays. In order to estimate the dynamic impulse responses of the emerging markets¡¦ return rates to random shocks in the U.S. return rates, the first essay uses block exogenous VAR models which suggested in the papers of Zha (1996), Cushman and Zha (1997), and Zha (1999), and it finds that return rates on the U.S. positively affect stock return rates of the four Asian markets. By using the method of Rapach and Wohar (2005a, 2006a), and the second essay also finds that return rates on the U.S. have in-sample and out-of-sample predictive ability for return rates of the respective emerging market. The last essay follows the econometric methodology of Bai and Perron (1998, 2003a, 2003b, and 2004) and it points out that there exists at least one structural change in the predictive regression model of the respective empirical equity market. The results suggest that an emerging equity market¡¦s sensitivity to shocks from the U.S. return rates is related to its degree of openness.

Retrovirus gene therapy vectors can deliver therapeutic genes to mammalian cells in a permanent manner by integrating their genome into host chromosomes and therefore provide the potential for long term therapeutic gene expression. Retrovirus integration, however, can be oncogenic. Apart from insertional mutagenesis (IM) genotoxicity may be caused by other factors including DNA damage following infection and integration and epigenetic effects related to incoming viral particles. Thus, using retrovirus and lentivirus infected murine tumour tissue and infected cell lines in vitro this thesis was directed at investigating whether virus infection and integration could cause genotoxicity by alternative route(s) other than IM. Using clonally derived liver tumours that developed in mice, and normal liver and kidney tissues, following EIAV and HIV delivery in utero, comparative genome hybridisation methodology was used to examine for copy number variation. This showed amplification and deletions only in EIAV derived tumours. Real time Q-PCR analysis was then used to measure gene expression changes relating to genes contained within or near to amplifications observed in two tumours of individual mice. The STRING database was then used to find networks linking genes with differential expression profiles and genes in one of these tumours identified with provirus insertions that were also differentially expressed. These data provided preliminary data implicating a role for LV in Hepatocellular carcinoma (HCC). DNA damage is known to cause chromosomal instability that can lead to tumour development. The relationship between double strand breaks (DSB) and virus infection was also investigated in-vitro to find alternative routes to genotoxicity other than IM. Cell viability analysis demonstrated cells with a defective DNA damage response (DDR) have decreased cell viability compared with cells with intact DDR when infected with RV or LV vectors. DSB assays showed RV and LV infection to generate foci over a 6 hour period followed by DDR. Where no viral integrase is present, no DDR appears, however, where the vector is used with or without a genome to infect cells, DDR occurs as shown by the presence of 53BP1 foci indicative of DNA damage. The relationship between DNA damage and methylation was also investigated. Global methylation was found elevated in the genomic DNA of LV and RV infected cells and not in control uninfected cells. In contrast, methylation changes were not found in infected cells lacking the NHEJ repair pathway. These data suggest the DNA damage response is linked to genome methylation. The E2F transcription factor plays a key role in regulating expression of genes known to control oncogenesis and cancer, and E2F is regulated by methylation of its related target gene promoters. Taking into account all genes in the human genome the number of genes that bind E2F is 32.77%. However, using microarray to represent genes differentially expressed after infection, 59% of these were E2F targets. Overall, taking the data obtained in this thesis into account it may be suggested that RV and LV infection causes a number of potentially related changes to cells that include DNA damage and repair and methylation changes that could influence E2F that is an important factor involved in oncogenesis. Combining this with IM, attenuated RV and LV currently in use for gene therapy may cause genotoxicity to infected cells and increase the risk of oncogenesis especially where DNA damage is not correctly repaired. Further work is required to show in greater detail the extent of this genotoxicity, possible by whole genome sequencing of treated host genomes or cell transformation assays linked to the genotoxicity assays presented here. Collectively these data show that alternative factors to IM might exist that could act independently or synergistically to IM.

Benzene is an ubiquitous pollutant and industrial solvent that has been identified as a human leukemogen. Early exposure to environmental carcinogens such as benzene has been postulated to play a role in the etiology of childhood leukemia, however the association remains controversial. Genotoxic agents such as benzene can cause an increase in the frequency of DNA double-strand breaks, which may remain unrepaired or result in the initiation of DNA recombinational repair mechanisms. The first objective was to investigate the induction of DNA double-strand breaks following in utero treatment to 200 mg/kg and 400 mg/kg benzene i.p. using the phosphorylated histone γ-H2A.X as a marker. Using immunoblotting, treatment with benzene did not increase the formation of γ-H2A.X in bone marrow cells of adult C57Bl/6N male mice and in maternal bone marrow, fetal liver, and post-natal bone marrow cells following in utero exposure to 200 mg/kg or 400 mg/kg benzene throughout gestational days 7 to 15. Secondly, the study investigated the induction of micronuclei following in utero exposure to benzene. Acute exposure to 400 mg/kg benzene resulted in a statistically significant increase in the percentage of micronucleated cells in adult male bone marrow cells. In utero exposure to 400 mg/kg benzene throughout gestational days 7 to 15 also caused a statistically significant increase in the percentage of micronucleated cells in maternal bone marrow and post-natal bone marrow cells. Fetal liver cells also demonstrated a statistically significant increase in the percentage of micronucleated cells following 200 mg/kg and 400 mg/kg benzene. The third objective was to investigate the initiation of DNA recombination following in utero exposure to benzene using the pKZ1 mutagenesis mouse model as a surrogate marker for non-homologous end joining activity. Adult pKZ1 mouse tissue yielded no recombination events; however, post-natal bone marrow cells did contain detectable recombination frequencies. iii In utero benzene exposure did cause an increasing trend in recombination events, and upon analysis of only the samples containing detectable levels of recombination, in utero exposure to 400 mg/kg of benzene caused a statistically significant increase in recombination frequency within this group. These results demonstrate that benzene does not increase the formation of γ-H2A.X after acute and in utero exposure, however, the induction of micronuclei following acute and in utero benzene exposure confirmed that benzene is a genotoxic agent causing chromosomal breaks. In utero benzene exposure increased the frequency of DNA recombination in bone marrow from post-natal day 9 pups exhibiting detectable levels of recombination. Further investigations into different types of DNA damage and repair pathways are warranted to fully elucidate the role of genotoxic mechanisms in the etiology of benzene-induced childhood leukemias. / Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2008-08-22 11:07:49.162

This thesis applies Atheoretical Regression Trees (ART) to the problem of locating changes in mean in a time series where the number and location of those changes are unknown. We undertook an extensive simulation study into ART's performance on a range of time series. We found ART to be a useful addition to currently established structural break methodologies such as the CUSUM and that due to Bai and Perron. ART was found to be useful in the analysis of long time series which are not practical to analyze with the optimal procedure of Bai and Perron. ART was applied to a long standing problem in the analysis of long memory time series. We propose two new methods based on ART for distinguishing between true long memory and spurious long memory due to structural breaks. These methods are fundamentally different from current tests and procedures intended to discriminate between the two sets of competing models. The methods were subjected to a simulation study and shown to be effective in discrimination between simple regime switching models and fractionally integrated processes. We applied the new methods to 16 realized volatility series and concluded they were not fractionally integrated series. All 16 series had mean shifts, some of which could be identified with historical events. We applied the new methods to a range of geophysical time series and concluded they were not fractional Gaussian noises. All of the series examined had mean shifts, some of which could be identified with known climatic changes. We conclude that our new methods are a significant advance in model discrimination in long memory series.

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Thesis (Ph. D.)--Cornell University, May, 2008. / Vita. Includes bibliographical references (leaves 125-133).