The rosy apple aphid, Dysaphis plantaginea, (Homoptera: Aphididae) is a serious pest of apples in British Columbia (BC), Canada and especially in organic orchards where conventional controls cannot be used. The goals of this study were to determine the environmental or management factors of an orchard that lead to high aphid populations, to conduct an economic assessment of the damage, to determine the timing of autumn migration, and to test several autumn and spring chemical control methods and two novel autumn mechanical control methods targeting the aphids while on their alternate host, Plantago major. To explain the variation among orchards, I evaluated several potential correlates of aphid density: abundance of the alternate host (plantain, Plantago major), foliar tree nitrogen, tree age, tree planting density, and the application of an oil treatment in spring. Stepwise regression indicated that foliar nitrogen and tree age explain 27% of the variation. Orchards receiving a spring oil application had a 53% lower average aphid infestation level. Plantain abundance was not related to aphid population on apple. However, experimental manipulation of leaf angle from the ground and size showed that significantly more alate and apterous aphids occurred on large, low angle leaves. Mowing prior to spring aphid migration was associated with 75% fewer alatae and apterae on the plantain. The loss in harvest resulting from aphid damage ranged from 3% to 76% of the crop. Effective autumn control depends on accurate timing of aphid flight. The peak of female flight occurred on the 27th of September, 2007 at 11:56 hours daylength (sunrise to sunset) and the peak of male flight occurred on the12th of October, 2007 at 11:02 hours daylength. Aphid densities in the spring of 2008 were very low, making comparisons between treatments and controls difficult. Autumn applications of Superior dormant oil and kaolin clay were not effective. The PureSpray Green treatments of two October applications and one April application showed a significant reduction in rosy apple aphid infested clusters compared with the untreated control. Mowing and rotavating did not result in a significant reduction in aphid infestation level.

Alternate Level of Care (ALC) patients are patients that stay in the acute care setting while waiting to be transferred to an ALC facility. They are not receiving the appropriate type of care and are occupying acute care resources. ALC patients occupy 5,200 patient beds everyday in Canada, and 12 percent of these ALC patients die during their waiting period. This study evaluates Toronto General Hospital's (TGH) discharge policy in the General Surgery and General Internal Medicine (GIM) departments using a discrete-event simulation. For long-term care ALC patients, it was found that applying to one extra application or maximizing the number of short waiting list facilities in their total number of applications significantly reduces the number of ALC days and the number of died in hospital patients. Knowing if discharge policies can decrease ALC days is not only significant to TGH but also to other health care institutions.

Alternate Level of Care (ALC) patients are patients that stay in the acute care setting while waiting to be transferred to an ALC facility. They are not receiving the appropriate type of care and are occupying acute care resources. ALC patients occupy 5,200 patient beds everyday in Canada, and 12 percent of these ALC patients die during their waiting period. This study evaluates Toronto General Hospital's (TGH) discharge policy in the General Surgery and General Internal Medicine (GIM) departments using a discrete-event simulation. For long-term care ALC patients, it was found that applying to one extra application or maximizing the number of short waiting list facilities in their total number of applications significantly reduces the number of ALC days and the number of died in hospital patients. Knowing if discharge policies can decrease ALC days is not only significant to TGH but also to other health care institutions.

This thesis concerns the occurrence of the large-scale bed and plan forms known as alternate bars and meandering, and the internal structures of the flow associated with their formation. The work is to be viewed as an extension of previous work by da Silva (1991), Yalin (1992), and Yalin and da Silva (2001). As a first step in this work, the criteria for occurrence of alternate bars and meandering of Yalin and da Silva (2001) is re-considered in view of additional field and laboratory data from the recent literature and data resulting from two series of experimental runs carried out in two sediment transport flumes. This leads to a number of modifications of the boundary-lines in the related existence-region diagram of Yalin and da Silva. The size of the largest horizontal coherent structures (HCS’s) of an alternate bar inducing flow was then investigated experimentally on the basis of three series of flow velocity measurements. These were carried out in a 21m-long, 1m-wide straight channel, conveying a 4cm-deep flow. The bed consisted of a silica sand having a grain size of 2mm; its surface was flat. The measurements were carried out using a Sontek 2D Micro ADV. The horizontal burst length was found to be between five and seven times the flow width. The effect of the HCS’s on the mean flow was also investigated. A slight internal meandering of the flow caused by the superimposition of burst-sequences on the mean flow was clearly detectable. Finally, with the aid of three new series of measurements in the same channel, an attempt was made to penetrate the dynamics and life-cycle of the HCS’s. For this purpose, quadrant analysis was used; the cross-sectional distribution of relevant statistical turbulence-related parameters was investigated; and cross-correlations of flow velocity along the flow depth and across the channel were performed. The analysis indicates that the HCS’s originate near the channel banks, with the location of ejections and sweeps being anti-symmetrically arranged with regard to the channel centreline, and then evolve so as to occupy the entire depth of the water and the entire width of the channel. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2010-03-09 10:20:53.596

No description available.

This thesis examines the role of the prophetic chronotope as a form of alternate, circular time in Baron Ludwig von Reizenstein’s gothic romance, The Mysteries of New Orleans. As the novel’s temporal structure seemingly contains the professed slave revolution through a manipulation of a linear prophetic sequence into circular time, Reizenstein simultaneously portrays a sexual revolution within the closed temporal system; however, as he localizes the sexual revolution in the “real time” of the reader through the inclusion of extra-textual artifacts, the novel’s closed system of alternate, circular time sustains a fissure, loosing all revolutionary potential, slave and sexual, into the reader’s temporality. Reizenstein compares sexual slavery, social restrictions on sexual expression, to chattel slavery, but recognizes it as endemic form of bondage affecting every race; therefore, Reizenstein uses chattel slavery as a ubiquitous circumstance in the U.S. South to identify other covert forms of slavery. In the end, the slave and sexual revolutions become the same conflict, and the restoration of beauty becomes its primary aim.

Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae), an important pest of maize, cotton and Phaseolus bean in West Africa, has never been described as a crop pest from East and southern Africa (ESA). It was hypothesized that in ESA it was either kept under control by natural enemies or that there exist several populations of M. nigrivenella with different host plant ranges. Another possibility is the mis-identification of the Mussidia species in ESA. Studies were conducted in Kenya between 2005 and 2007 to assess the species diversity and host plant range of Mussidia spp. and spatial distribution studies were done on selected host plants. Later, based on the results of host plant range, surveys were conducted between 2006 and 2007 in mid-altitude coastal Kenya to establish a catalogue of parasitoids associated with Mussidia spp. The suitability of stem borers found in Kenya for development of Trichogrammatoidea sp. nr lutea Girault (Hymenoptera: Trichogrammatoidea) and the factors affecting the bionomics of Mussidia sp. in the laboratory were examined. Eight plant species were found to host two Mussidia spp. and six putative morphospecies, which occur sympatrically in the coastal region. The two Mussidia spp. were Mussidia fiorii Ceconni and de Joannis and M. nr nigrivenella. Only one Mussidia sp., M.Jiorii, was found attacking one host plant species in the mid-altitude regions. In general, the host plant range was much narrower than in West Africa. Mussidia nr nigrivenella and Mussidia "madagascariensis" larval distribution was aggregated on Canavalia cathartica Thouars. (Fabaceae) and Strychnos madagascariensis Poir. (Loganiaceae), respectively, while the distribution of M. fiorii adults on Kigelia africana (Lam.) Benth. (Bignoniaceae) was regular. Eight parasitoid species were recovered from Mussidia spp. eggs and larvae and include the trichogrammatid egg parasitoid Trichogrammatoidea sp. nr lutea Girault, a braconid egg-larval parasitoid, Phanerotoma sp., the bethylid Goniozus sp. and the braconid Apanteles sp. Moreover, the ichneumonid larval parasitoid Syzeuctus sp. was obtained from M. fiorii, while the tachinid Leskia sp. was obtained from M, "madagascariensis". Trichogrammatoidea sp. nr lutea, the only parasitoid species which was successfully reared in the laboratory, successfully attacked and developed on eggs of six lepidopteran hosts indicating its potential to exploit other alternate lepidopteran pests of maize in West Africa. Like the parasitoid species, only one Mussidia sp., M.fiorii, was successfully reared in the laboratory and it developed on maize seed-, Canavalia enseiformes L. DC (Fabaceae) seed- and maize leaf-based diets while it could not develop on Mucuna pruriens L. DC (Fabaceae) seed- and C. cathartica seed-based diets. The lower developmental thresholds for M. fiorii eggs, larvae, pupae and egg to adult were found to be 12.8±0.25°C, 14.4±0.27°C, 11.0±0.03°C and 13.5i0.2rc, respectively, while the thermal constants were 82.0±1.61, 384.6±9.43, 144.9±6.84 and 588.2±10.81 degree days, respectively. Adults started emerging during the last hour of photophase and peak emergence was observed in the 2nd hour of scotophase. Mating activity largely took place between the 4th and 5th hour of scotophase. It can be concluded that there exist several Mussidia spp. in Africa that vary in their host plant range. Overall, mortality caused by parasitoids was negligible hence they were unlikely to explain the population dynamics of the Mussidia spp. in Kenya. The fact that Trichogrammatoidea sp. nr lutea successfully attacks and develops in six lepidopteran hosts, including two Mussidia spp. indicates its potential for use as a biological agent against M. nigrivenella in West Africa. Mussidia fiorii was able to develop on diets based on maize and C. enseiformes. The knowledge on dietary and thermal requirements would optimize mass production of the host and natural enemies. The present study revealed again a serious bottleneck for biocontrol worldwide, namely the proper identification of the pest and natural enemy species as a result of an ever dwindling number of taxonomists. We therefore suggest that molecular (DNA) techniques should be used in addition to detailed morphological examination. In view of the fact that natural control will not be effective in case of accidental introduction of the West African M. nigrivenella into Kenya, we suggest stringent precautions during movement of grains especially maize between the West Africa region and Kenya. / Thesis (Ph.D. (Environmental Sciences and Management))--North-West University, Potchefstroom Campus, 2009.

Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae), an important pest of maize, cotton and Phaseolus bean in West Africa, has never been described as a crop pest from East and southern Africa (ESA). It was hypothesized that in ESA it was either kept under control by natural enemies or that there exist several populations of M. nigrivenella with different host plant ranges. Another possibility is the mis-identification of the Mussidia species in ESA. Studies were conducted in Kenya between 2005 and 2007 to assess the species diversity and host plant range of Mussidia spp. and spatial distribution studies were done on selected host plants. Later, based on the results of host plant range, surveys were conducted between 2006 and 2007 in mid-altitude coastal Kenya to establish a catalogue of parasitoids associated with Mussidia spp. The suitability of stem borers found in Kenya for development of Trichogrammatoidea sp. nr lutea Girault (Hymenoptera: Trichogrammatoidea) and the factors affecting the bionomics of Mussidia sp. in the laboratory were examined. Eight plant species were found to host two Mussidia spp. and six putative morphospecies, which occur sympatrically in the coastal region. The two Mussidia spp. were Mussidia fiorii Ceconni and de Joannis and M. nr nigrivenella. Only one Mussidia sp., M.Jiorii, was found attacking one host plant species in the mid-altitude regions. In general, the host plant range was much narrower than in West Africa. Mussidia nr nigrivenella and Mussidia "madagascariensis" larval distribution was aggregated on Canavalia cathartica Thouars. (Fabaceae) and Strychnos madagascariensis Poir. (Loganiaceae), respectively, while the distribution of M. fiorii adults on Kigelia africana (Lam.) Benth. (Bignoniaceae) was regular. Eight parasitoid species were recovered from Mussidia spp. eggs and larvae and include the trichogrammatid egg parasitoid Trichogrammatoidea sp. nr lutea Girault, a braconid egg-larval parasitoid, Phanerotoma sp., the bethylid Goniozus sp. and the braconid Apanteles sp. Moreover, the ichneumonid larval parasitoid Syzeuctus sp. was obtained from M. fiorii, while the tachinid Leskia sp. was obtained from M, "madagascariensis". Trichogrammatoidea sp. nr lutea, the only parasitoid species which was successfully reared in the laboratory, successfully attacked and developed on eggs of six lepidopteran hosts indicating its potential to exploit other alternate lepidopteran pests of maize in West Africa. Like the parasitoid species, only one Mussidia sp., M.fiorii, was successfully reared in the laboratory and it developed on maize seed-, Canavalia enseiformes L. DC (Fabaceae) seed- and maize leaf-based diets while it could not develop on Mucuna pruriens L. DC (Fabaceae) seed- and C. cathartica seed-based diets. The lower developmental thresholds for M. fiorii eggs, larvae, pupae and egg to adult were found to be 12.8±0.25°C, 14.4±0.27°C, 11.0±0.03°C and 13.5i0.2rc, respectively, while the thermal constants were 82.0±1.61, 384.6±9.43, 144.9±6.84 and 588.2±10.81 degree days, respectively. Adults started emerging during the last hour of photophase and peak emergence was observed in the 2nd hour of scotophase. Mating activity largely took place between the 4th and 5th hour of scotophase. It can be concluded that there exist several Mussidia spp. in Africa that vary in their host plant range. Overall, mortality caused by parasitoids was negligible hence they were unlikely to explain the population dynamics of the Mussidia spp. in Kenya. The fact that Trichogrammatoidea sp. nr lutea successfully attacks and develops in six lepidopteran hosts, including two Mussidia spp. indicates its potential for use as a biological agent against M. nigrivenella in West Africa. Mussidia fiorii was able to develop on diets based on maize and C. enseiformes. The knowledge on dietary and thermal requirements would optimize mass production of the host and natural enemies. The present study revealed again a serious bottleneck for biocontrol worldwide, namely the proper identification of the pest and natural enemy species as a result of an ever dwindling number of taxonomists. We therefore suggest that molecular (DNA) techniques should be used in addition to detailed morphological examination. In view of the fact that natural control will not be effective in case of accidental introduction of the West African M. nigrivenella into Kenya, we suggest stringent precautions during movement of grains especially maize between the West Africa region and Kenya. / Thesis (Ph.D. (Environmental Sciences and Management))--North-West University, Potchefstroom Campus, 2009.

Ste2p and Ste3p are well-characterized yeast pheromone G-protein Coupled Receptors (GPCR) those are involved in the signaling of mating responses that lead to cell fusion. Their signaling–associated interactions with G-protein/MAPK signal transduction machinery are well established, homologous to those in mammalian systems, and serve as a simplified model system in GPCR research. While the arrestin- mediated biased signaling mechanism of mammalian GPCR has not been discovered for the pheromone receptors, a recent demonstration of α-arrestins being involved in the internalization of the pheromone GPCR, Ste2p was reported. The present study was designed to reevaluate and extend the alternate functionality for pheromone receptors and to determine the role of yeast arrestins in the yeast mating. Specific residues in the TM6 of Ste2p exhibiting strong mating and constitutive MAPK signaling were combined and investigated in terms of their effect on MAPK signal transduction leading to cell cycle arrest as well as their impact on downstream mating projection formation and zygote formation events. Our findings indicate that Ste2p possess as specific residues that govern its relative bias for mediating MAPK signaling or mating events. Relative dose response experiments accounting for systemic and observation bias for these mutations yielded evidence of mutational-derived functional biases for Ste2p and further validated the alternate pheromone dependent functionalities for Ste2p. Further, arrestin knockout and knock-in studies showed that Art1 (Ldb19) is selectively involved in the regulation of zygote formation but not MAPK signal transduction following the binding of ligand to Ste2p receptors. In addition, ligand stimulated selective localization of Art1 (Ldb19) to the mating projection, implicating it in the regulation of downstream mating functionalities. Overall, while leaving the full mechanism of alternate/biased Ste2p signaling to be elucidated, these results highlight the possibility of continued relevance of the yeast pheromone-mating pathway as a simplified model for GPCR research in the context of arrestin-mediated biased GPCR signaling.

Search engines of today are focusing on efficiently and accurately generating search results.Yet, there is much to be explored in the way people interact with the applications and relate to the content. Individuals are commonly unique, with complex preferences, motives and expectations. Not only is it important to be sensitive to these differences, but to accommodate the extremes. Enhancing a search engine does not only rely on technological development, but to explore potential user experiences in broader perspectives - which not only gratifies the needs for information, but supports a diversity of journeys. The aim of the project is to develop an alternate search engine with different functionality based on new values that reflects contemporary needs. The result, Exposeek, is an experiential prototype supporting exploratory browsing based on principles of distributed infrastructure, transparent computation and serendipitous information. Suggestive queries, legible algorithms and augmented results provide additional insights and present an alternative way to seek and peruse the Web. / Search Engines, Interaction Design