In this study, the adaptation and response of Aspergillus nidulans and Aspergillus fumigatus wild type and cpcA strains to antifungal compounds were studied using cultural, genetic and proteomic methods. CpcA is the fungal cross pathway control protein which may also have a role in the development of resistance to antifungal that has become a major problem in human and plant fungal diseases and many studies are devoted to address the drug resistance mechanisms. Cell adapts itself to stress when it is subjected to a stress repeatedly. The ancestor of CpcA, ATF4 (CREB2) has recently been found to be important in the survival of tumor cells after starvation and nutrient limitation and these findings are expected to open new insights into the future antifungal therapy. Fungal cross pathway control system conserves similar mechanism with the stress response pathway in humans as a response to amino acid starvation. Fungal adaptation to antifungal agents was studied using the genetic model A. nidulans with the experimentally induced adaptation setup. It was concluded that A. nidulans cells are able to adapt to antifungal. In order to understand how cell becomes resistant to a previously susceptible agent, it is important to investigate the process when the cell encounters the agent for the first time. Fungal cellular response to antifungal drugs was studied using the human opportunistic pathogen A. fumigatus at the protein level. This is the first proteomic study directed to investigate the A. fumigatus response to voriconazole (VRC). The recently developed two dimensional gel electrophoresis approach, Fluorescence 2-D Differential Gel Electrophoresis (DIGE) method was applied to visualize differentially expressed proteins. It was concluded that, about 150 proteins were differentially regulated as a response to stress exerted by azole group antifungal drugs. cpcA strains of A. nidulans and A. fumigatus were compared to wild type strains in terms of susceptibility to various stresses, adaptation potential also at the proteome level. The results obtained in this study showed that CpcA was important in the response of Aspergillus to oxidative, heat stress and in the adaptation of cells to VRC and that its absence drastically changed the cellular response to VRC at the protein level by changing the expression of about 80 proteins. Thus, this protein is a good candidate in future as a potential drug resistance mediator and further characterization is needed to elucidate its mechanism of action on drug resistance.

Iodine is a biophilic element with one natural long-lived isotope, 129I (t1/2= 15.6 million years), and one stable isotope, 127I. The inventory of 129I in surface environments has been overwhelmed by anthropogenic releases over the past 50 years. The objective of this study is to utilize the elevated concentration and biophilic nature of 129I and the isotopic ratio of iodine (129I/127I) as a tracer of water mass movement and organic matter. Additionally, the significantly elevated values of 129I/127I could provide a geochronometer, similar to the way 14C is used, particularly for terrestrial organic matter that is less than 50 years old. A series of laboratory experiments and field investigations were carried out to characterize the dominant chemical forms of dissolved iodine, i.e., iodide (I-), iodate (IO 3-), and organic iodine (DOI) in natural waters. Sensitive methods were developed for the analysis of nanomolar quantities of 127I species in a variety of environmental systems using high performance liquid chromatography (HPLC) and an organic iodine decomposition technique, dehydrohalogenation. The potential use of 129I/127I as a hydrological tracer was evaluated through measurements of 129I and 127I, which were carried out in wells in the artificially recharged ground water basin of Orange County, California. Literature values of aquifer ages based on 3H/3He and δ18O tracer data, as well as time-series data of chloride and Santa Ana River flow rates over the past decade were compared to values for 129I and 127I. The iodine isotopes demonstrated a conservative behavior in these aquifers, suggesting that the observed variations of these isotopes reflect past river flow conditions during the time of recharge. The feasibility of using 129I/127I ratios to trace terrestrial organic matter across an estuary was tested. A novel analytical technique to determine 129I/127I ratios in DOI was developed for this investigation. The results of a Galveston Bay transect clearly show that 129I/127I ratios in DOI can remain elevated up to salinity of about 15, but that 129I/127I values of inorganic iodine species do not show any trend with change in salinity gradient due to fast isotopic and chemical equilibration in the estuarine waters.

This dissertation investigated locational risks to ecosystem health associated with proximity to industrial complexes. The study was performed at the behest of ranchers and citizens living and working down-prevailing wind from the Formosa Plastics, Inc. and ALCOA facilities located in Calhoun County, Texas. Concerns expressed were for potential genotoxicity resulting from exposure to complex chemical mixtures released by the facilities. Exposure assessment of the marine environment was performed with sediments and oysters from Lavaca Bay being analyzed. Numerous chemicals were found to be present at concentrations considered likely to result in adverse responses in exposed populations. Bayesian geostatistical analysis was performed to determine if the concentrations were affected by a spatial process. Mercury and polycyclic aromatic hydrocarbons were the most notable of the chemicals found to be present at elevated concentrations and affected by a spatial process. Evaluation of maps generated from spatial modeling revealed that proximity to ALCOA resulted in elevated risks for exposure to harmful concentrations of pollutants. Genotoxicity was measured in two sentinel species. Oysters (Crassostrea virginica) were utilized for evaluation of the marine environment and cattle (Bos taurus and Bos taurus crossbred cattle) were chosen for evaluation of the terrestrial environment. Chromosomal aberration analysis was performed on oyster hematocytes. Analysis of the results failed to demonstrate the presence of an important generalized spatial process but some specific locations close to the ALCOA plant had elevations in this measure of genotoxicity. Stress as measured by the lysosomal destabilization assay was also performed on oyster hematocytes. These results were found to be affected by a significant spatial process with the highest degree of destabilization occurring in close proximity to ALCOA. Genotoxicity in cattle was evaluated with the single cell gel electrophoresis assay and chromosomal aberration analysis. Bayesian geostatistical analyis revealed the presence of important spatial processes. DNA-protein cross-linkage was the most notable with a strong indication of increased damage down-prevailing wind from the industrial complexes. Results indicated that proximity to industrial facilities increased the risk for harmful exposures, genotoxicity, and lysosomal destabilization.

This study investigated the spatiotemporal distribution of abundances of the fish eggs and Engraulid eggs in relation to environmental factors along the coastal waters off southwestern Taiwan. Moreover, the key to fish eggs under an optical microscope in winter(January) was revised. Samplings were carried out on a bimonthly basis. In total, 38 tows were conducted from January to November 2003.The samplings of eggs were collected by horizontal hauls with NORPAC and cyclindricalconic net at the water surface along Jiading, Linyuan and Fangliao. Sea surface temperature, sea surface salinity, dissolve oxygen, chlorophyll a concentration and density were measured simultaneously with a seabird CTD. The spatiotemporal distribution of the total eggs abundances of two kinds of nets were very similar, and more the abundance of cyclindricalconic net than the NORPAC net. Therefore, the total eggs abundance and species of cyclindricalconic net were adopted to investigate the spatiotemporal distribution of the eggs along the coastal waters off southwestern Taiwan. The total abundances of fish eggs demonstrated significant seasonal variations highest in July and lowest in November. The geographical difference was also observed that the highest abundances were recorded at Jiading, and followed by Linyuan and Fangliao. Based on the results of correlation analyses, it was revealed that the spatiotemporal fluctuations in the total abundances of fish eggs were significant positive correlated to the monthly variation of precipitation. 2,110 fish eggs were obtained from six samples in January, 2003, including Ophichthidae, Clupeidae, Synodontidae, Scaridae, Callionymidae, Soleidae , Cynoglossidae and Engraulidae. The fish eggs that couldn¡¦t be identified were firstly sorted into 28 groups by the egg shape, size, and membrane pattern. Furthermore, they were stored into 64 species based on the presence or absence, and the pattern of pigmentation. The group BIII, Engraulids eggs and unknown dead eggs were the top three dominant species. Due to the different composition of the dominant species, there were significant differences in the spatial distribution. The species composition of dominant group were the Callionymids eggs and unknown dead eggs in Jiading. The species composition of dominance group were group BIII , Engraulids eggs and unknown dead eggs in Linyuan, and Fangliao. In 2003, Engraulids eggs were very abundant in the coastal waters off southwestern Taiwan, representing 14% of the total fish egg abundances. Two peaks of Engraulids eggs abundances were found. One in the July to September 2003, and other one in January 2003. Spatial distribution in the abundances were also observed that the highest abundances were recorded at Fangliao, and followed by Linyuan and Jiading. The mortality rate of the Engraulids eggs was the reverse trends and spatial distribution of the Engraulids eggs abundances. The abundances of eggs were increased when precipitation was high and abundance of Amphipoda was low. The shape of Engraulids eggs was displayed regional differences. Engraulids eggs in Jiading and Fangliao were elongated shape, and oval shape in Linyuan. Seasonal variation in the egg shape was observed and also segregated into two groups representing elongated eggs group in May, July and September and oval eggs group in January, March and November, respectively. Engraulids eggs longitudinal diameter was significantly positive correlated with the SST and monthly precipitation, and were negatively correlated with sea surface salinity, dissolve oxygen and density. Maybe the group BIII was Mugilids eggs. Their spawning ground occurred in Linyuan. Furthermore, the spawning ground of both Callionymids eggs and Synodontids eggs were at Linyuan and Fangliao. The main spawning grounds of Engraulids eggs were at Linyuan and Fangliao along the coastal waters off southwestern Taiwan. The peak spawning season were in summer and winter 2003. The spawning time of Engraulids eggs was approximately at 00:00 to 01:00. The spatiotemporal variations of Engraulids eggs size were influenced by the alternation of the spawning grounds of Engraulids fish along the coastal waters off southwestern Taiwan.

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 162-168). Also available on the Internet.

Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xi, 150 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.

Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 121-138). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 96-118).

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 155-180). Also available on the World Wide Web.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2009. / Härtill 5 uppsatser.