Disinfection and environmental studies on pathogenic free-living amoebae : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Microbiology at Massey University

Over the last fifteen years, there has been an increasing awareness of sporadic cases of Primary Amoebic Meningoencephalitis (PAM), affecting primarily younger age groups and appearing in an acute fulminant form. The earliest positive case known, may have been in England in 1909. The pathogenic free-living amoebae (PFLA), which comprises the genera Naegleria and Acanthamoeba, are the causative organisms of PAM and Granulomatous Amoebic Encephalitis (GAE) respectively. PAM is a rapidly fatal disease affecting the central nervous system (CNS), and GAE although essentially confined to the CNS, may also take the form of granulomata in the liver, spleen, uterus and kidneys. A study on the disinfecting potential of Baquacil in axenic conditions, for comparison with the disinfecting potential of the chlorine, chlorine dioxide, ozone and Deciquam 222, showed that the order of effectiveness as amoebicides was Baquacil, chlorine, chlorine dioxide, ozone and Deciquam 222 in hard water. In soft water the order is Deciquam 222, Baquacil, chlorine, chlorine dioxide and ozone. Further study on the effect of Baquacil, chlorine and chlorine dioxide on amoebae, in conditions involving the use of a known Biochemical Oxygen Demand (BOD), a known bacteria concentration, and a combination of BOD and bacteria, confirmed Baquacil as a more effective amoebicide than chlorine, which in turn was more effective than chlorine dioxide. The concentrations of each disinfectant required were increased by the presence of a BOD, and of bacteria. The bacteria were preferentially destroyed over the amoebae with all three disinfectants. Baquacil resistant clones of Naegleria fowleri were isolated, although it is not known whether this resistance is due to genetic or physiological variation. Axenically and Monoxenically cultured amoebae were used, the latter to increase the resemblance of the amoebae to those found in the environment. Differences in survival rates were observed, the monoxenically cultured amoebae invariably having higher survival rates. Competition studies were done with Naegleria spp. and T.pyriformis on three bacteria species, after preliminary studies on the ability of the two protozoa to grow on eight species of bacteria. Of the three bacteria used in the competiton studies, Escherichia coli and Enterobacter cloacae were shown to support both Naegleria spp. and T.pyriformis, with the ciliate increasing in numbers by up to 3 fold over the controls, but the amoebae were affected only slightly, with a small decrease in numbers compared to the controls. A synergistic relationship was evident on the third bacteria species, Pseudomonas fluorescens, between Naegleria spp. and T.pyriformis, where as in the controls, this bacterium was not a good growth support bacteria for either protozoan

Atomization of synthetic and real samples using heated graphite atomizers for atomic absorption spectroscopy : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University

The interference effects caused by a number of matrices including compounds such as NaC1, HC1, KBr, HNO3, H3PO4, H2SO4 on Cu, Pb, Cd and A1 atomic absorption signals when the elements are atomized from three non-flame graphite atomizers (furnace, cup and rod) are studied over several concentration ranges. Investigations show that most of the interferences found occur in the vapour phase. A comprehensive literature survey has been done and from this survey and the experimental work carried out, discussions are presented on the postulated mechanisms of interference. Two main theories are given for the vapour phase interference, i) entrapment of the atom in the matrix particle forming in the vapour, ii) rapid molecular condensation in the vapour phase. Several degrees of interference (both enhancement and depression) were obtained for the different chemical and atomization systems used. Attempts were made at rationalizing the degree and type of interference in terms of the postulated models. Supporting evidence for the atom entrapment theory was gained from an investigation of the nature of the non-atomic absorption peak obtained mainly when a1ka1i halides are present in the sample. Evidence is produced showing that the absorption spectra obtained from alkali halides here and by other workers are charge-transfer spectra. An investigation into the use of a graphite atomizer for zinc ana1ysis in bovine serum is presented and compared to determinations using flame atomic absorption on the same samples

Motivated Spanish learning among Anglo-Texan high school students : an exploration of theories, research, and experience, with implications for pedagogy

textResearch into foreign language and second language learning motivation has progressed steadily over the past half century. Several theories and models have been developed to explain how learners are motivated to learn a foreign language. Context-specific research, however, is lacking for Anglo-Texan high school students learning Spanish. This report applies the theories of foreign language learning motivation to this context, using personal experience and anecdotes from the author as a Spanish teacher and student, in order to prescribe pedagogical applications of the research for high school Spanish teachers in Texas who seek to increase their students' motivation.Curriculum and Instructio

An analogue of Bauer’s theorem for closed orbits of skew products

In this article we prove an analogue of Bauer’s theorem from algebraic number theory in the context of hyperbolic systems

Mortgage Foreclosures in Atlanta: Patterns and Policy Issues

Metropolitan Atlanta is experiencing a foreclosure boom as the number of failed mortgages more than doubled in less than five years, between 2000 and 2005. These foreclosures impose significant costs not only on borrowers and lenders, but also on municipal governments, neighboring homeowners and others with a financial interest in nearby properties. As a result, foreclosure avoidance strategies must involve not only federal, state and local public agencies, but also responsible mortgage industry officials, consumer groups, and community-based, not-for profit organizations. This report was commissioned by Doug Dylla at NeighborWorks America to help build awareness of foreclosure problems and craft a comprehensive foreclosure-avoidance strategy for metropolitan Atlanta. The work presented here serves as a companion to the Foreclosure Prevention Forum cosponsored by NeighborWorks America and the Atlanta Federal Reserve on May 23, 2005. The forum brought together more than 150 leaders from the mortgage industry, state and local government, the advocacy community, and academic and policy researchers. These participants generated a variety of collaborative approaches to address issues related to mortgage failures and foreclosures in the Atlanta region.The report was written and researched by Mark Duda and William Apgar. It expands on research presented by Duda at the forum and is intended to characterize the current situation with respect to mortgage failures in metropolitan Atlanta, as well as previous research completed by the authors on foreclosure avoidance in Chicago and Los Angeles. The foreclosure data used in this report were generously provided by EquiSystems, LLC, producer of the Atlanta Foreclosure Report

Has risk management in private equity kept pace with rapid growth?

The Federal Reserve System's Private Equity Merchant Banking Knowledge Center, formed at the Chicago Fed in 2000 after the Gramm-Leach-Bliley Act was passed, sponsors an annual conference on new industry developments. This article summarizes the 2007 conference, Private Equity Has Gone Big... Has Risk Management Kept Pace?, held August 2-3.Risk management

Navigating the new world of private equity - a conference summary

The Federal Reserve System's Private Equity Merchant Banking Knowledge Center, formed at the Chicago Fed in 2000 shortly after the passage of the Gramm–Leach–Bliley Act, sponsors an annual conference on new industry developments. This article summarizes the 2008 conference held on July 9 - 10.Private equity ; Investments

Former Socialist Economies and the Undergraduate Curriculum

The authors report on the results of a survey of current undergraduate instruction on the socialist economic system and post-socialist economies. Based on responses from eighty colleges and universities, they evaluate how course offerings and content have changed in light of the momentous developments of the past decade. The evidence is then used to comment on trends and potential future developments in classes on comparative economic systems and transition economies. Although undergraduate offerings in these areas have arrived at a short-run equilibrium, there are good reasons to believe that the structure of the courses should soon be re-thought.college teaching, socialist systems, transition economies