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Ecological effects of Ulva lactuca L. in Avon-Heathcote EstuaryMurphy, Gerry January 2006 (has links)
Macroalgal blooms are increasing world-wide and have negative effects on benthic invertebrates and sediments. These include loss of species diversity and development of hostile sediment environments. This thesis considers ecological effects of Ulva lactuca L., and its mechanical removal on benthic invertebrates and sediments in Avon-Heathcote Estuary, New Zealand. Benthic communities comprised 34 species from 12 groups recorded from seven sites during seasonal general surveys. Dominant groups at each site were Gastropoda and Bivalvia. The most abundant species were Austrovenus stutchburyi, Micrelenchus tenebrosus and Amphibola crenata. Community composition varied significantly between sites, and there were significant site-specific differences in abundances of most species between winter and summer. U. lactuca had the greatest seasonal variation. Several species correlated with U. lactuca biomass, and the strength of correlation for different species varied between sites. There were seasonal changes in sediment physico-chemical variables between sites with greatest change in the silt/clay fraction. The sediment variables silt/clay fraction, dissolved oxygen and temperature correlated with seasonal changes of patterns in benthic community assemblages. A similar study was carried out by Bressington in 2003. In both studies, Bivalvia and Gastropoda were the most abundant groups, with Gastropoda having a higher, and Bivalvia a lower, proportion in the present study compared with 2003. Summer communities were significantly different between the two studies. Compared with 2003 there were higher percentages of sediment pore water and volatile solids present in 2005. Experimental removal of U. lactuca was conducted by mechanical broom at two sites: an open, exposed central sand flat, and McCormacks Bay, a shallow, sheltered mud flat. Removing U. lactuca had several immediate effects. These included a significant decrease in abundance of mobile epifauna (Micrelenchus tenebrosus and Zeacumantus subcarinatus) and an increase in abundance of infauna, including Arthritica bifurca and Austrovenus stutchburyi. There was no effect of U. lactuca removal on Austrovenus stutchburyi condition and 46 days following removal, invertebrate abundances approached pre-removal levels at each site. U. lactuca removal also caused short-term increases in dissolved oxygen and temperature of pore water. The greatest visual impact of removing U. lactuca was to sediments in McCormacks Bay from trampling. It was concluded that the variables having the greatest effect on seasonal species distribution and abundance at each site were temperature and sediment grain size. Differences between the present study and the study in 2003 were due to differences in sampling procedure mainly due to the two different quadrat sizes. Greater accuracy in representing long-term changes in ecosystems would be achieved by using standard sampling protocols. Removal of U. lactuca by mechanical broom was effective and had low impact on benthic invertebrates and physico-chemical variables, but it should be used only in sandy habitats because of severe disturbance to soft-sediment environments. Options for management and control of U. lactuca in Avon-Heathcote Estuary are discussed.
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Syndicated Loans in the United States (1995-2000): Announcement Effects, Long-Term Performance and Capital Structure Issues from a Borrower Perspective.K.Le@murdoch.edu.au, Kim-Song Le January 2007 (has links)
This thesis examines the impact of announcements of syndicated loans on the share prices of borrowing firms. I use a sample of 5,465 loan observations reported in the International Financing Review Platinum database to study this impact. Event study methodology is used. My overall results show significantly positive wealth effects on the borrowing firms. However, when I partition my data set into revolving credit agreements, term loans and hybrid loans, I find that the results are driven primarily by revolving credit agreements. I also observe that the size of the event window plays an important role in identifying the wealth effects for the borrowers. A five-day event window (-2, +2) shows share price response to revolving credit announcements to be significantly positive. A three-day event window (-1, +1) reveals that announcements are statistically positive for revolving credit agreements and statistically negative for term loan announcements. My results are consistent with previous studies in this area. I also distinguish between financial press announcements and information provider (IFR) announcements to cater for the potential for reporting bias. I find that both the IFR and financial press announcements are significant for the five-day window, but only the financial press results are significant for the three-day window. My study is unique in that I differentiate the impact of different sources of information on the market reaction to borrower share price.
In addition to the examination of the wealth effect, I also use the structure of the loans to examine the uniqueness of bank loans and their ability to provide financial slack. Specifically, I examine whether revolving credit loans or term loans or hybrid loans make bank loans unique and their ability to provide financial slack. I observe that out of the three structures of bank loan, only revolving credit loans allow the borrower to more precisely match the funds acquired with the firmâs investment needs and to market time by borrowing at times when financing costs are attractive. Revolving credit loans are positively valued by the market both initially and over the longer term. Bank loans reduce information asymmetry, but the renegotiation characteristics of revolving credit loans allow borrowers to exploit changes in the interest rate environment, thus providing support for the market timing theory of capital structure. In contrast to puzzling results of previous studies, I present evidence of long-term positive performance following bank loans.
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An analysis of connectivity /Al Karim, Tayeb. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (p. 49-52).
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Long-wave ultraviolet radiation (UVA1) and visible light : therapeutic and adverse effects in human skin /Wiegleb Edström, Desiree, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.
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Risk-factors, prevention and treatment of early complications after allogeneic haematopoietic stem cell transplantation /Hägglund, Hans, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.
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Inflammation and wound healing following photorefractive keratectomy /Tomás Barberán, Santiago, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
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Molecular monitoring of engraftment and leukemia relapse after allogeneic hematopoietic stem cell transplantation /Mattsson, Jonas, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.
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Allergy to laboratory animals : risk factors for development of allergy and methods for measuring airborne rodent allergens /Renström, Anne, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.
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Pesticide use in rice cultivation in Tarapoto, Peru : pesticide residues in blood of farmers, usage behaviour, and health care practices /Lange, Gun, January 2006 (has links) (PDF)
Examensarbete.
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The influence of context on message-making and audience reception in graphic design /Kirchoff, Sarah M. January 2008 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 2008. / Typescript. Supplemental DVD+R contains a PDF version of the thesis. Includes bibliographical references (leaves 149-152).
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