In South Africa, the assessment of the suitability and acceptability of water for drinking purposes is done according to the South African National Standards (SANS) 241 (2006) which requires that Cryptosporidium and Giardia in drinking water should be less than 1 oocyst/10l and 1 cyst/10l respectively. Although there is a requirement to monitor for these parasitic protozoans, there is lack of uniformity in the monitoring approach. Therefore, the objective of the study was to develop a protocol/methodology that can be applied by drinking water producers to monitor Cryptosporidium and Giardia to ensure that the risk of exposure to these organisms and the risks of non–compliance to guidelines are reduced. Also, to test the feasibility of the protocol on a small system, the drinking water purification plant at the Vaal River Barrage Reservoir that supplies approximately 350 people with drinking water. The protocol for monitoring of Cryptosporidium and Giardia was developed based on monitoring procedures proposed by the US Environmental Protection Agency, the Drinking Water Inspectorate, Australia, New Zealand, and especially on the risk based procedure followed by Northern Ireland with the intention that it will be applicable to all water supply systems irrespective of size and system complexity of the purification works. It is focused on a preventative approach of monitoring Cryptosporidium and Giardia and it consists of ten steps which are: (i) Assessment of the monitoring requirements, (ii) Description and characterization of the source water types (iii) Abstraction of source water (iv) Assessment of the water purification plant (v) Water quality monitoring (vi) Cryptosporidiosis and Giardiasis outbreak (vii) Risk assessment (viii) Sample collection and Laboratory processing (ix) Data evaluation, interpretation and storage (x) Process evaluation and review. As stated, the developed protocol was tested at a small purification plants situated at the dam wall of the Vaal River Barrage catchment, Gauteng Province . From this assessment it was evident that steps of the protocol were easy to follow and the possible risks in the water value chain i.e. from source water to the supply of purified drinking water could be identified. Some of the challenges encountered during the application of the protocol include difficulty in obtaining detailed information regarding the activities around the catchment and information on the prevalence of cryptosporidiosis and giardiasis in the local community or in South Africa in general. From this study, it could be concluded that the source water from the Vaal River Barrage Reservoir was high risk. However, the use of the multi–barrier approach coupled with advanced treatment of UV rendered the water drinking supplied to the local community within the South African Drinking Water Standards for from Cryptosporidium and Giardia of less than 1 oocyst/10l and 1 cyst/10l. The protocol for the monitoring of Cryptosporidium and Giardia could contribute to the protection of drinking water consumers by identifying high risk source waters, identifying areas that can be improved in the water treatment system and also protecting the catchment areas from further faecal pollution. With respect to this outcome, the developed protocol could be used by water utilities as part of their Water Safety Plans to optimize monitoring. Furthermore, this methodology has a potential to contribute to the blue drop certification as it should for part of the Water Safety Plans. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.

In South Africa, the assessment of the suitability and acceptability of water for drinking purposes is done according to the South African National Standards (SANS) 241 (2006) which requires that Cryptosporidium and Giardia in drinking water should be less than 1 oocyst/10l and 1 cyst/10l respectively. Although there is a requirement to monitor for these parasitic protozoans, there is lack of uniformity in the monitoring approach. Therefore, the objective of the study was to develop a protocol/methodology that can be applied by drinking water producers to monitor Cryptosporidium and Giardia to ensure that the risk of exposure to these organisms and the risks of non–compliance to guidelines are reduced. Also, to test the feasibility of the protocol on a small system, the drinking water purification plant at the Vaal River Barrage Reservoir that supplies approximately 350 people with drinking water. The protocol for monitoring of Cryptosporidium and Giardia was developed based on monitoring procedures proposed by the US Environmental Protection Agency, the Drinking Water Inspectorate, Australia, New Zealand, and especially on the risk based procedure followed by Northern Ireland with the intention that it will be applicable to all water supply systems irrespective of size and system complexity of the purification works. It is focused on a preventative approach of monitoring Cryptosporidium and Giardia and it consists of ten steps which are: (i) Assessment of the monitoring requirements, (ii) Description and characterization of the source water types (iii) Abstraction of source water (iv) Assessment of the water purification plant (v) Water quality monitoring (vi) Cryptosporidiosis and Giardiasis outbreak (vii) Risk assessment (viii) Sample collection and Laboratory processing (ix) Data evaluation, interpretation and storage (x) Process evaluation and review. As stated, the developed protocol was tested at a small purification plants situated at the dam wall of the Vaal River Barrage catchment, Gauteng Province . From this assessment it was evident that steps of the protocol were easy to follow and the possible risks in the water value chain i.e. from source water to the supply of purified drinking water could be identified. Some of the challenges encountered during the application of the protocol include difficulty in obtaining detailed information regarding the activities around the catchment and information on the prevalence of cryptosporidiosis and giardiasis in the local community or in South Africa in general. From this study, it could be concluded that the source water from the Vaal River Barrage Reservoir was high risk. However, the use of the multi–barrier approach coupled with advanced treatment of UV rendered the water drinking supplied to the local community within the South African Drinking Water Standards for from Cryptosporidium and Giardia of less than 1 oocyst/10l and 1 cyst/10l. The protocol for the monitoring of Cryptosporidium and Giardia could contribute to the protection of drinking water consumers by identifying high risk source waters, identifying areas that can be improved in the water treatment system and also protecting the catchment areas from further faecal pollution. With respect to this outcome, the developed protocol could be used by water utilities as part of their Water Safety Plans to optimize monitoring. Furthermore, this methodology has a potential to contribute to the blue drop certification as it should for part of the Water Safety Plans. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2011.

The handset product has been styled in successive years to reach more compact sizes and there has as a result been a reduction in volume available to house antennas; therefore size/performance trade-offs have had to become accommodated. Some of the issues antenna engineers are currently confronted with include; frequency shifting due to the antenna not being isolated from the handset, far field pattern deformation due to close proximity effects from the energy absorbing human tissues, distortion caused by noise from electronic components that share the handheld platform. What is required is antenna technology, which maintains a high enough performance despite the escalating restrictions imposed by the demands of the market. Research is performed on a twisted loop antenna topology that possesses an integral balun as part of its structure. Two rudimentary designs are utilised in the research, a simple bifilar structure that can be adapted for GSM, peN, Bluetooth and W-LAN applications, and a quadrifilar helix structure for use in GPS. Both structures are based on existing industrial dielectricloaded antenna structures but are modelled as novel air-loaded structures using a commercially available Method of Moments (MoM) electromagnetic simulator. In this fashion, the antennas could be generated quickly with low computational requirements. A parametric study is performed on the bifilar antenna structure to gain an enhanced understanding of the twisted loop topology. Once this understanding is achieved proposed modifications to the structure are implemented to improve the performance of the antenna. The main subject of improvement is the broadening of bandwidth as normally dielectric-loaded antennas have inherent narrow bandwidth. Any improvements made on the air-loaded structures could be tested on dielectric structures in future research. The most successful novel approach attempted to increase the bandwidth in the twisted loop structure was the insertion of parasitic helices to create a coupled multi-pole filter response. In conjunction with the work performed on the bifilar, an air-loaded GPS quadrifilar helix antenna was also modelled. A method for inducing circular polarisation is proposed and then by the insertion of parasitics into the quadrifilar helix design a novel dual-band dual-polarised antenna is presented. Finally measurements are made to demonstrate the advantageous properties the dielectric-loaded GPS antenna has over conventional GPS antennas.

Thesis (Ph. D.)--University of Hawaii at Manoa, 1991. / Includes bibliographical references (leaves 167-173) / Microfiche. / xxiv, 212 leaves, bound 29 cm

Some parasites may modify the behavior of their hosts. Altered behaviors may: 1) benefit the host in that they defend against the pathogen, 2) benefit the pathogen and represent manipulations of the host response, and 3) benefit neither the host or the pathogen and simply be a product of the host response to infection. In this thesis I examine four host/parasite systems. For each system, I explore host/parasite behavioral interactions, and examine them with regard to selective pressures that may be acting on both the host and the parasite. I test the Hamilton and Zuk hypothese in 26 species of lizards. I find an inverse relationship between a lizard species' brightness and parasite prevalence. My result lend credence to criticisms of the Hamilton and Zuk Hypothesis. If infection does occur, animals may alter their behavior to impair the growth and reproduction of the parasite. To test this prediction, I examine behavioral thermoregulation in two strains of the snail Biomphalaria glabrata, one resistant to, and one susceptible to, the parasite Schistosoma mansoni. The preferred temperature of infected snails drops five weeks after exposure to the parasite. I propose the hypothesis that pathogen-induced host defense responses result in altered host behaviors and enhanced predation. In particular, I examine the effects of the acute phase response (a physiological response whose symptoms include fever, reduced activity and malaise) on antipredatory behavior in bullfrog (Rana catesbeiana) tadpoles. This host response is associated with the preliminary stages of infection with many pathogens yet its behavioral effects have received little attention. I find that the stereotypical effects of the acute phase response can lead to increased predation. I suggest that altered behaviors may afford some parasites a potential pathway to their next host. I examine the behavioral effects of a yeast, Candida spp., a single-host parasite species in its natural host, the red-legged frog (Rana aurora). Infected tadpoles exhibit the same behavioral modifications that are noted in bacteria injected bullfrog tadpoles. These results suggest that some altered behaviors may occur due to a host response to infection and not due to parasitic manipulation. / Graduation date: 1993

Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M. Ag. Sc.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1997. / Includes bibliographical references (leaves 87-96).

Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 161-172).

Thesis (Ph. D.)--Ohio State University, 2007.

Thesis (M.S.P.H.)--University of Michigan, 1938.