Geodesic knots in cusped hyperbolic 3-manifolds

We consider the existence of simple closed geodesics or "geodesic knots" in finite volume orientable hyperbolic 3-manifolds. Previous results show that at least one geodesic knot always exists [Bull. London Math. Soc. 31(1) (1999) 81-86], and that certain arithmetic manifolds contain infinitely many geodesic knots [J. Diff. Geom. 38 (1993) 545-558], [Experimental Mathematics 10(3) (2001) 419-436]. In this paper we show that all cusped orientable finite volume hyperbolic 3-manifolds contain infinitely many geodesic knots. Our proof is constructive, and the infinite family of geodesic knots produced approach a limiting infinite simple geodesic in the manifold.Comment: This is the version published by Algebraic & Geometric Topology on 19 November 200

From Indicators to Action: Evaluating the Usefulness of Indicators to Move from Regional Climate Change Assessment to Local Adaptation Implementation

As the effects of climate change become increasingly damaging and costly, a public and political consensus is building for planning that will protect private property and public infrastructure. Climate-related planning has primarily focused on mitigation, assessing vulnerability, and building adaptive capacity. Adaptation has not gained substantial ground in the area of implementation. The uncertainty associated with climate change projection and variability has emerged as a dominant barrier to adaptation. However, as knowledge accrues, the global and national science communities have been developing more detailed, fine-scale climate projections. Regional climate assessments are available for the sub-national climate regions in the U.S., and have been created based on the measurement of many components of climate, often referred to as indicators. This thesis evaluates the use of those and other indicators as adaptation decision support tools. Findings suggest that indicators can be effectively integrated into a step-wise, risk-based adaptation planning process to overcome barriers to adaptation, many of which contain concern over climate change uncertainty at their core. The combination of climate science data and information about the local experience of climate change are found to be key to the effective use of indicators in adaptation, as is the direct integration of indicators into the policy-making process. Ideally, these indicators can be used to inform trigger points for phases in a flexible adaptation approach, but more work is needed to develop methods for managing the risks and costs associated with adaptation

Giardia intestinalis : aerobic metabolism and physiology of in vitro growth : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in microbiology at Massey University, Palmerston North, New Zealand

G. intestinalis; the causative agent of giardiasis, parasitises a number of vertebrates including man; and has a worldwide distribution. Although giardiasis is now a widely recognised public health concern; little is known of its aetiological agent. This is primarily due to the fact that a protocol for the routine axenic cultivation of this intestinal parasite was not available until 1976. With the advent of in vitro cultivation, an increasing number of reports have outlined the in vitro growth requirements of G. intestinalis; however; the physiology and unique metabolism of this protozoan still require further clarification. Utilising two strains of G. intestinalis (Bris/83/HEPU/106 and Hast/87/MUGU/68), the influences of envirornnental factors such as pH and temperature on axenic culture growth were investigated. Variations in both temperature and pH were shown to effect the in vitro growth rate of the two strains examined. Growth of Bris/83/HEFU/106 was markedly impaired at non-optimal temperature; (optimal growth of Bris/83/HEPU/106 and Hast/87/MUGU/68 occurred at 37°c); while growth of Hast/87/MUGU/68 continued, at a reduced rate, over a wider, non-optimal temperature range (30-40°c). Both strains exhibited marked pH optima for culture growth (pH 6. 75-7.50) with a rapid decline in culture growth rates outside these pH levels. Clonal growth of G. intestinalis trophozoites in semi-solid agarose has been utilised in the past as an assay of trophozoite viability in vitro. The suitability of such an assay for use during this study was investigated for both Bris/83/HEPU/106 and Hast/87/MUGU/68. Over the range of agarose concentrations examined, the colony fonning efficiency (CFE) of both strains was extremely variable. While Hast/87jMUGU/68 was better adapted to growth in agarose medium, with CFE of up to 60% recorded; these rates of clonal growth were often not reproducible, as the growth of trophozoite colonies remained inconsistent despite duplication of all assays. The thiol reducing agent L-cysteine, has been reported to be a specific growth requirement of G. intestinalis in vitro. The correlation between reducing conditions and the growth and attachment of Bris/83/HEPU/106 and Hast/87jMUGU/68 in culture, was investigated as trophozoites were exposed to a range of L-cysteine concentrations in TYl-S-33 growth medium. Enhanced growth of experimental cultures was directly related to increases in L­ cysteine concentration and corresponding decreases in the 0-R Potential of growth medium. Culture growth occurred at a maximal rate where the concentration of L-cysteine in growth medium exceeded 0.15% w/v. All cultures failed to grow in the absence of L­ cysteine. Trophozoite attachment in culture was most rapid during the 30-90 minutes following culture establishment. Under elevated L-cysteine concentrations (0.15-0.25% w/v) this attachment reached maximal levels (85-95%). In the absence of L-cysteine, attachment of trophozoites in culture continued, but at a markedly reduced rate. The oxygen sensitivity of G. intestinalis trophozoites was investigated in TYl-S-33 utilising a protocol developed during this study, where the exposure of trophozoites to dissolved oxygen was directly controlled through adjustment of oxygen flow into growth medium. Bris/83/HEPU/106 and Hast/87jMUGU/68 trophozoites displayed a similar degree of oxygen sensitivity at 37°c. A slow decline in culture viability was recorded upon exposure of trophozoites to 4.0- 6.0 ppm dissolved oxygen in growth medium. At 8.0 ppm; exponential killing of trophozoites was preceded by a 'lag phase' of 3-4 hours duration. In contrast; the killing of cultures commenced almost immediately after exposure of trophozoites to 12.0 ppm dissolved oxygen. At temperatures below 37°c (20°c and 3o0 C) , Bris/83/HEPU/106 exhibited a reduced sensitivity to elevated dissolved oxygen levels in TYl-S-33, as both the T1/2 of killing, and the lag phases preceding this killing were extended. The basis for the observed 'temperature-dependant' oxygen sensitivity of G. intestinalis is not known. Oxygen consumption by G. intestinalis has recently been reported by several workers; however; there is still very little known of the metabolic role of 'active respiration' in this 'aerotolerant anaerobe'. Consumption of oxygen by Hast/87jMUGU/68 in PBS was demonstrated. using a Model 97-08 Oxygen Electrode. Dissolved oxygen was removed from PBS by trophozoites at a rate of 3.2-5.3 10- 9 ppm/cell/hr. This oxygen consumption was inhibited. up to 50% by the flavoantagonist, Quinacrine dihydrochloride, at concentrations of 250-1000 µg/ml in PBS solution. Tbe concentrations of Quinacrine which were inhibitory to oxygen consumption by trophozoites over a 5 hour period were well in excess of the Quinacrine MLC (Minimum Lethal Concentration)

Images of men and women reflected in magazine advertisements in 1962 and 1973

http://www.worldcat.org/oclc/1860373

A Co-Creative Transformation Process: The Art of Adults Learning Together in CPE Group

Working with adults learning together in CPE

A follow-up study of families referred from a child psychiatric clinic

Thesis (M.S.)--Boston Universit

Slave Labor: The Taft-Hartley Act and the Tri-State Mining District

Before World War II, there was an unstable atmosphere to the industrial sector of the United States economy. As World War II began the industries settled down, and the production of means for the war boomed, as the employees joined together against the Axis powers. After the war, the sense of duty that many union members felt disappeared and the mining industries began to reveal extensive problems with labor relations. Because of these two factors, the Taft-Hartley act was compiled through a joint committee in June 1947. In the act, there were many provisions made to protect both the employer and employees from union pressure, protect the unions from infiltration by the \u27commies,\u27 and regulate union members\u27 strikes, and much more. Many labor organizations believed this to be an attack on unions and its members. Employers believed the act protected employee and employer alike; but the disagreement over the act between these two sectors of the businesses resulted in a fight for and against the act. The Taft-Hartley act caused a propaganda war between unions and industries in Oklahoma that lasted for a decade and affected legislation and elections from 1947 to about 1952, until the Landrum-Griffin act of 1959 amended the act. The unions launched their campaign against the act during 1947, when the Republican Congress was considering many pieces of labor legislation. They unionized one of their largest unions, the United Mine Workers Association to speak out against this act. One of the major associations that supported the act in Oklahoma was the Associated Industries of Oklahoma. Both, the union and the employers association, were sending their propaganda to Picher, Oklahoma, thus affecting the small mining town\u27s perception on the Taft-Hartley Act. The association of employers launched a campaign to the employers in Oklahoma against the Unions, sending out pamphlets that described horror stories of union intimidation and sabatoging Democrats. These pamphlets, sent by the association, made it to the owners of mines in Picher, Oklahoma, who were trying to persuade them to follow suit and protest against repealing the act. Because of such propaganda war fare, this act proceeded to be one of the most tumultuous pieces of labor legislation in the twentieth century