The ever-growing world population raises the concern and necessity of rational use and distribution of limited water resources. Water deficit is the single most dominant abiotic factor limiting cotton (Gossypium hirsutum L.) yield in drought-prone Texas croplands. Characterizing plant traits conferring drought tolerance to cotton genotypes and then transferring this information back to breeders and geneticists have the potential of significantly increasing and stabilizing production statewide. Although a plethora of physiological studies have been conducted and have demonstrated that drought tolerance in plants is likely to be conferred by a combination of plant traits rather than a single trait, this knowledge has not translated into improved breeding lines. Experiments were conducted in 2010 and 2011 in the Drought Tolerance Laboratory (Texas AgriLife Research and Extension Center in Corpus Christi, TX) to analyze the responses of cotton genotypes to different levels of water stress. This facility is equipped with computerized systems capable of continuously monitoring whole-plant water use as well as several environmental parameters. Sixteen cotton genotypes were provided by Monsanto Co. and the Texas AgriLife Cotton Improvement Programs at College Station and Lubbock. Seeds were pre-germinated in wet paper towels and then hand planted in large pots previously filled with fritted clay. A total of 3 and 8 (2010 and 2011, respectively) pots containing plants of each genotype were permanently placed on micro-lysimeters for continuous measurement of water use. Water regimes were imposed in 2010 (well-watered and water-stressed), and 2011 (water-stressed) when plants reached the early-flowering stage and were carried until plants reached maturity (100% open bolls). Data collected showed that genotypes have very distinct water use patterns. The water stress treatment imposed on the test plants negatively affected plant growth that was indicated by a lower plant height, total number of leaves, and main-stem nodes of stressed plants when contrasted to their well-watered counterparts. Stomatal density was remarkably different among genotypes and a higher density was found on the abaxial (lower) leaf surface for all genotypes studied. Root dry mass production had different responses depending upon the severity of the water stress. Highest root dry mass was observed when plants were exposed to a mild stress and lowest when a more severe water restriction was imposed.

The growth of mass tourism has placed great pressure on British seaside destinations, and has contributed to the social costs experienced by the resident population via symptoms of changing perceptions, attitudes and behaviour towards tourism, and the presence of higher crime rates. This thesis examines the social reality experienced by residents, and determines the impacts of tourism-related crime upon two tourist communities which are experiencing high levels of crime. The comparative study of a British seaside resort and a coastal town reveals that tourism communities are influenced by individual resident opinions. Simultaneously these communities influence resident perception and behaviour towards tourism-related crime, and it is through this exchange process, that evidence of destination specific criteria has emerged. The research established that the resort community found commonality through the mutual gaze, whilst the coastal community formed closed perceptions of deviant activities through discord and the local gaze. The study concludes by arguing that a destination offering a hedonistic lifestyle will not necessarily have higher crime rates than other safer destinations. This is due to the widespread implementation of crime prevention methods in the resort, and the lack of deterrents established in the coastal town. Therefore there may be nothing criminogenic about these particular destinations. Instead, collective community perception, digressed through crime talk, has influenced community crime interpretation and individual resident evaluation of the tourism industry.

This dissertation is a sociolinguistic investigation into the system of the speech act of complimenting among young Japanese. Sociolinguistic studies on complimenting have been rather extensively carried out in Western academic discourse since the 1980s. The rapid development of this field went hand in hand with the existing growing body of work on speech acts, linguistic politeness and language and gender studies, all fields which came to flourish during the 1960s-80s. The speech act of complimenting has so far been overwhelmingly regarded as one of the most obvious positive politeness strategies (Brown & Levinson 1987; Holmes 1995) and also as a feminised sociolinguistic practice (Eckert & McConnell-Ginet 2003; Herbert 1990). However, the sociolinguistic examination of complimenting in non- Western speech communities remains less well investigated. This dissertation challenges some traditional premises about the nature of this speech act and explores how sociolinguists should go about analysing this variable in the context of a non-Western speech community. In so doing, I highlight that applying localized cultural knowledge plays a crucial role in unfolding the social and linguistic systems of complimenting in a Japanese speech community. The analysis presented here draws on a corpus consisting of more than 40 hours of recordings with 67 young Japanese university students, collected through ethnographic techniques. Fieldwork was conducted for over a year in order to obtain these data in southern Japan (namely, Kumamoto and Oita prefectures). A total of 369 compliment utterances within 143 compliment sequences were extracted and transcribed from this corpus. To achieve a satisfying sociolinguistic understanding of this speech act, the data are analysed with a combination of both the qualitative methods of discourse analysis and the quantitative methods of variationist sociolinguistics. This dissertation brings much needed discussions of this variable situated within non-Western contexts and hence makes significant contribution to the field, by adding new perspectives and findings about complimenting behaviour. On the one hand, my work found some regularity in compliments which parallel the findings of previous studies. This itself is a new insight in the field of compliments studies, namely, that there are crossculturally (if not universally) pervasive properties of complimenting. On the other hand, this study highlighted some originality in this speech act among the young Japanese. The construction and application of compliments in the case of Japanese substantially manifest its complex and intricate sociolinguistic system, which my dissertation is dedicated to describing through the naturally occurring data of spoken Japanese.

Faculty of Science School of Animal Plant and Enviromental Sciences 0404336v lmcnamara@gpf.co.za / Pine saw timber plantation forestry on the Eastern Escarpment of South Africa contributes significantly to the economy of the country. Losses to plantation value through fire, insects and disease, and particularly over the last decade, losses due to baboon damage are of serious concern. Anecdotal evidence indicated that baboons damage pine trees shortly following pruning operations and at certain times of the year. A perception existed that damage has increased dramatically, yet no documented evidence to this effect is available. As a result two physiological studies were undertaken to investigate whether changes in nutrient concentration of inner bark tissues of pine trees on the Eastern Escarpment of South Africa, act as triggers for baboon damage. A literature review was also undertaken to document the extent of baboon damage, tree volume and associated economic costs. A comparison was made with Zimbabwe, where baboon damage is quoted to be a severe threat to the continued viability of plantation forestry. The first study investigated changes in nutrient concentration of the soft, inner bark tissue of Pinus patula, in response to pruning measured in five year old plantations in the Mpumalanga Province, South Africa. Samples of tissues were collected from pruned and unpruned trees at 2, 7, 14 and 28 days after 26% of the live crown had been removed in the pruning treatment. Results indicated that live pruning of Pinus patula did not influence nutrient concentration of inner bark tissues at set intervals post pruning. Treatment differences of aggregate data for sample interval showed that potassium concentration increased by 0.03% whereas magnesium concentration decreased by 0.02% following pruning. Aggregate data for treatment showed that phosphorus, carbohydrates (fructose, glucose, sucrose and starch), boron and nitrogen concentration, and moisture content of inner bark tissues varied during the short time period of the study. Variations are attributed to iv the commencement of growth, translocation of nutrients from needles and branches and possibly moisture stress. Results from the study do not support anecdotal evidence that baboon damage to pine plantations which increases shortly after pruning operations is as a direct physiological response to the pruning event. In this study it is much more likely that changes in nutrient concentrations coincided with a remobilization of resources in response to seasonal triggers. In the second study, nutrient concentrations of the inner bark of Pinus patula and Pinus taeda growing on the Eastern Escarpment of South Africa were studied over a seasonal cycle in order to investigate the allegations that baboon damage in the plantations was related to the degree of nutrient remobilization. Significant differences were found in phosphorus concentration and moisture content across seasons and between baboon damaged and undamaged trees. Undamaged Pinus taeda trees recorded the highest phosphorus levels in April 2003 (0.13%). Moisture content was lowest in damaged Pinus patula trees in August 2003 (57%). Anecdotal evidence that baboon damage to pine trees on the Eastern Escarpment of Mpumalanga increases prior to the growing season is supported by the significant changes in inner bark tissue concentration. Nutrient translocation prior to needle fall alters inner bark nutrient concentration, as does moisture stress and demand for nutrients prior to cambial activity. Pine bark is easier to peel during periods of peak cambial activity. These factors are discussed as they may trigger baboon damage. Significantly higher inner bark tissue concentrations of sucrose (4.25 versus 2.61%), starch (4.75 versus 2.84%) and nitrogen (0.61 versus 0.49%) in Pinus taeda compared with Pinus patula, supports anecdotal evidence that Pinus taeda is preferentially damaged by baboons. Baboon damaged trees contained higher concentrations of zinc (30.4 versus 22.3 ppm) and calcium (0.26 versus 0.20%), and lower concentrations of sucrose (2.95 versus 3.91%) and starch (3.21 versus v 4.39%) than undamaged trees, which was attributed to resource allocation to wound response and not that baboons selected trees with higher concentrations of zinc or calcium. The variability of inner bark tissue concentration due to a number of factors highlights that baboon damage in pine plantations is not readily answered, and remains a complex problem. A literature review was undertaken of reported baboon damage occurrence and intensity of damage, following statements that baboon damage to pine plantations is rapidly escalating in the Mpumalanga Province, South Africa. The extent and intensity of baboon damage from the first reported damage (1960’s) until current levels are documented. A comparison is made between Zimbabwe and South Africa where the baboon damage is viewed as a serious problem. The extent of baboon damage in Zimbabwe, expressed as the total percentage of area damaged by baboons as a function of the total area planted to pine for the period 2000-2004 has escalated from 10.8 to 13.3% despite harvesting activities removing damaged trees (Fergusson, 2004). The total area with reported baboon damage in Zimbabwe amounted to 5 317 hectares in 2004 (Fergusson, 2004). In South Africa baboon damage has increased markedly from the first reports of 300 hectares in 1980 (Bigalke, 1980) to 7 641 hectares in 2004. The average percentage of trees damaged in affected compartments is 20.4% with the percentage increasing from 17.2 to 23.6% from 2002-2004. Pinus taeda appears to be the most severely affected species with Pinus elliottii showing increasing levels of damage in many compartments in 2004. Quantifying the value lost by baboon damage to the industry requires reliable assessment methods that are cost effective to implement. Assessment methods need to take into account the position of the damage on the stem, and resultant saw log value that is lost. Assessment methods implemented in South Africa and Zimbabwe are described, and results given by method applied. A standard assessment method is required for comparisons to be made between areas vi with baboon damage. An investigation in Zimbabwe highlighted significant differences between standing tree volume estimations (4.98 – 7.59 m3/ha, with various methods), and actual volume losses (50.45 m3/ha) (Ngorima et. al., 2002). The associated Rand value loss determined by the South African assessment method in 2004 was in excess of 20 million Rand. This estimated loss in revenue does not include losses of incremental growth due to the damage, re-establishment costs, loss of thinning and clearfelling product revenue due to timber wastage, or losses experienced in down line processing at the saw mill. The extent of the baboon damage problem warrants proactive management, continued monitoring and investment into research in order to gain a better understanding of the problem. The increase in the extent of baboon damage from early documented figures is most alarming, showing that the baboon damage problem continues to grow.

Childhood trauma exposure is associated with a range of adverse outcomes, including post-traumatic stress disorder (PTSD). Parents are often children’s main source of support following a trauma. However, little is known about the experiences of parents in supporting their child post-trauma and research into the relationship between parenting and childhood PTSD has yielded mixed findings. The five papers in this thesis aimed to investigate the role of parental responses in child adjustment following child trauma exposure. Paper 1 presents a meta-analytic review of the association between parenting and child PTSD symptoms. A small, yet highly significant relationship between parenting and child PTSD was identified, but given the limited number of studies available and the potential influence of methodological factors, only tentative conclusions are made. Nonetheless, the finding that parenting is associated with child PTSD informed the following four papers in this thesis. Paper 2 qualitatively examined parents’ experiences of supporting their children following single-incident trauma and presentation at an Emergency Department. As no child in Paper 2 accessed psychological treatment post-trauma, Paper 3 presents an investigation of parents’ views of providing care for children with clinically significant levels of post-traumatic distress. The trauma-specific aspects of parental support identified in Papers 2 and 3 highlight the need for a validated measure of post-trauma parental responses. Paper 4 describes the development and preliminary evaluation of a measure of parental appraisals and behaviours following trauma exposure. Finally, the majority of studies that examined parenting behaviours in Paper 1 were conducted in a Western, low-risk context; therefore, the aim of Paper 5 was to examine the views of parents of trauma exposed children in the peri-urban settlement of Khayelitsha, South Africa. Overall, the results indicate that parental responses are associated with child PTSD symptoms and highlight the strategies used by parents to promote child recovery.

Immune responses are presumed to contribute to host fitness, either by fighting off infections or via immunopathology. Research in this thesis sought to relate the magnitude of a putative immune response to infection and host and parasite fitness. The experiments and field studies presented here all focus on the interactions between the freshwater crustacean, Daphnia magna and its sterilizing bacterial endoparasite, Pasteuria ramosa, using the number of circulating haemocytes as a measure of host immune activity. I found substantial genetic variation in Daphnia’s cellular response to P. ramosa, and that Daphnia genotypes that mount the strongest cellular responses are the most likely to get infected and suffer sterilization. Thus, a strong cellular response is associated with low, as opposed to high host fitness potential. There were also some host genotypes that mounted a weaker cellular response and did not go on to suffer infection, and some that lacked a cellular response and also never suffered infection with P. ramosa. These findings led to a heuristic two-stage model for infection, where the parasite has to (1) pass from the host gut to haemolymph and then (2) successfully overcome haemolymph-based immune effectors to reproduce and achieve fitness. I also demonstrate that both the magnitude of host cellular response and likelihood of infection increases with initial parasite dose in susceptible host genotypes, and that host cellular response is associated with likely infection under both host and parasite genetic variation. Parasitised Daphnia also have substantially more circulating haemocytes than their healthy counterparts in both the laboratory and in the wild, where there is substantial genetic and environmental variation. This is one of the very few examples of how an immune response designates low host and high parasite fitness potential in a wild system. Finally, using a mixture of field study and common garden experiment, I demonstrate evolution in parasite infection traits over the course of an epidemic in a wild population, and that this evolution is associated with a decline in host abundance.

Rotor-dynamic stability is a very important subject impacting the design, control, maintenance, and operating safety and reliability of rotary mechanical systems. As rotor-dynamic nonlinearities are significantly more prominent at higher rotary speeds, the demand for better and improved performance achievable through higher speeds has rendered the use of a linear approach for rotor-dynamic analysis both inadequate and ineffective. To establish the fundamental knowledge base necessary for addressing the need, it is essential that nonlinear rotor-dynamic responses indicative of the causes of nonlinearity, along with the bifurcated dynamic states of instability, be fully characterized. The objectives of the research are to study the various rotor-dynamic instabilities induced by crack breathing and bearing fluid film forces using a model rotor-bearing system and to investigate the applicability of the fundamental concept of instantaneous frequency for characterizing rotor-dynamic nonlinear responses. A comprehensive finite element model incorporating translational and rotational inertia, bending stiffness and gyroscopic moment is developed. The intrinsic modes extracted using the Empirical Mode Decomposition along with their instantaneous frequencies resolved using the Hilbert transform are applied to characterize the inception and progression of bifurcations suggestive of the changing rotor-dynamic state and impending instability. The dissertation presents and demonstrates an effective approach that integrates nonlinear rotor-dynamics, instantaneous time-frequency analysis, advanced notions of dynamic system diagnostics and numerical modeling applied to the detection and identification of sensitive variations indicative of a bifurcated dynamic state. All presented studies on rotor response subjected to various system configurations and ranges of parameters show good agreements with published results. Under the influence of crack opening, the rotor-bearing model system displays transitional behaviors typical of a nonlinear dynamic system, going from periodic to period-doubling, chaotic to eventual failure. When film forces are also considered, the model system demonstrates very different behaviors and failures from different settings and ranges of control parameters. As a result, a dynamic failure curve differentiating zones of stability and bifurcated instability from zones of dynamic failure is constructed and proposed as an alternative to the traditional stability chart. Observations and results such as these have important practical implications on the design and safe operation of high performance rotary machinery.

A wound- and insect-inducible expression system for transgenic plants was developed. Specifically, I demonstrate wound- and insect-inducible, localized gene expression driven by the potato proteinase inhibitor II (pinII)-promoter in transformed Arabidopsis, tobacco and white spruce. As reporter and target genes driven by the pinII-promoter, I used the GUS gene and a terpenoid synthase gene, respectively. In addition, I found that the pinII-promoter drives trichome-specific, systemically-induced gene expression in tobacco and Arabidopsis. Finally, I demonstrate that the pinII–promoter, when transformed into Arabidopsis, is extremely sensitive to subtle, low-impact stress treatment. This latter finding prompted me to use, in the second part of my thesis, the pinII-promoter in conjunction with GUS reporter gene expression to test if intact Arabidopsis plants can respond to exposure to monoterpene volatiles. My experiments using the pinII–promoter GUS reporter system clearly established that Arabidopsis plants respond to the exposure of the monoterpene volatiles tested. It is thought that monoterpenes and other volatiles can act as airborne signals between plants under stress or between distant parts of the same plant. At the outset of my thesis research, and to some extent still today, the concept of plant-plant signalling with volatiles has been met with scepticism. After establishing that Arabidopsis plants do respond in a laboratory setting to certain monoterpene volatiles, I further tested the extent of the response at the transcriptome level using a 30 K microarray platform. The gene expression analysis revealed several hundred transcripts that respond with a change of abundance in response to treatment of intact Arabidopsis plants with the monoterpenes ocimene or myrcene. Many of these transcripts were annotated as stress and defense genes including genes involved in octadecanoid signaling. Real-time PCR analyses of octadecanoid mutants confirmed a role for octadecanoid signaling in the response to the monoterpene ocimene. In addition, treatment with ocimene or myrcene caused increased levels of methyl jasmonate (MeJA) in Arabidopsis rosette leaves. However, plants treated with monoterpene prior to wounding or feeding by cabbage looper did not reveal any significant priming effect for these pre-treatments.

Despite the availability of live attenuated measles virus vaccines, a large number of measles-associated deaths occur among infants in developing countries during the "window of susceptibility" (age 4-9 months). During this period declining maternal antibody titers are no longer protective against wild-type measles virus (MV) and impede successful immunization with the live attenuated vaccines. Therefore, the development of a safe vaccine that would induce protective immunity in the presence of maternally derived MV-specific antibodies in young infants and would close the "window of susceptibility" is desirable. Since adenoviruses have been shown as suitable vaccine candidates capable of eliciting potent protection against mucosal infectious diseases, the ability of an adenovirus-vectored anti-measles vaccine to elicit robust immune responses against MV was assessed in this study. Mice immunized intramuscularly or intranasally with a combination of human adenovirus serotype 5 (Ad5) recombinants expressing MV hemagglutinin (H) and fusion (F) glycoproteins developed MV-specific neutralizing antibody titers similar for both routes of immunization. However, intramuscular immunization of mice with Ad5 recombinants resulted in induction of a predominant T helper type (Th1) immune response, whereas intranasal immunization induced a balanced Th1/Th2 immune response. Furthermore, intranasal immunization resulted in increased titers of MV-specific immunoglobulin A (IgA) in lungs in comparison to intramuscularly immunized animals. The ability of the Ad5 recombinants to induce protective immune responses in cotton rats by different routes of administration was also evaluated. Cotton rats that received a single dose of the Ad5 recombinants intramuscularly or intranasally experienced a rise in MV-specific neutralizing antibody titers and reduction of the viral RNA load in the lung tissue after intranasal MV challenge. In addition, the largest reduction in viral replication was observed in the group of cotton rats inoculated with the Ad5 recombinants intranasally. Based on these observations, the Ad5-based vaccine appears to be a suitable candidate against measles. Furthermore, a capability of purified globular head domain of MV H protein produced in a human cell line to induce MV-specific immune responses in mice was tested. Subcutaneous immunization of mice with the recombinant protein alone resulted in both humoral and cell-mediated immunity, characterized by the production of MV-specific serum IgG and neutralizing antibodies, as well as interferon-gamma and interleukin 5 (IL-5) production by in vitro restimulated splenocytes. The former responses were further enhanced by formulation of the protein with aluminium hydroxide. However, very low numbers of INF-gamma secreting cells and low levels of IgG2a in the serum suggested a Th2 immune response. Novel adjuvants (Th1-directing), as well as MV F protein should be considered for the inclusion into the vaccine formulations to induce more balanced Th1/Th2 immune responses against measles.

Background The mechanism by which allergies trigger asthma occurs through the interaction of antigen, IgE and the FcεR1 receptor on mast cells resulting in the release of mediators that exert their effects on various surrounding tissues causing bronchoconstriction, plasma exudation and mucus hypersecretion. The response is usually maximal within 30 minutes and resolves spontaneously within two hours. At least half of the individuals who exhibit this so called early response also manifest a late response which is a subsequent episode of bronchoconstriction that is usually maximal around six hours following exposure and involves airway inflammation. Montelukast has proven efficacious in the management of asthma and desloratadine is effective in the treatment of allergic rhinitis and chronic idiopathic urticaria. Since the early response involves the actions of multiple mediators, including histamine and the leukotrienes, the question of whether concurrent mediator blockade would be superior to either agent alone was raised. Additionally, the recent evidence supporting anti-inflammatory activity for these agents suggested potential efficacy against the late airway response. Methods Two double-blind, randomized, placebo-controlled, 4-way crossover allergen inhalation challenge investigations were conducted in twenty (10 per investigation) mild atopic asthmatics. The early response investigation involved the administration of either 5 mg desloratadine, 10 mg montelukast, the combination , or placebo (Vitamin B1) at 26 hours and 2 hours prior to allergen inhalation. The late response investigation involved single dose administration of each agent, alone or in combination, 2 hours prior to allergen inhalation. Measurements of changes in airway responsiveness and inflammation were also conducted. Results The early response was significantly inhibited by montelukast and the combination. Desloratadine did not differ from placebo. The late response was significantly decreased by desloratadine and montelukast and completely blocked with the combination. Desloratadine decreased sputum eosinophils at 7 hours, montelukast at 24 hours, and the combination at both time points. Airway responsiveness to methacholine trended lower with montelukast and the combination. Montelukast was the only treatment to significantly decrease exhaled nitric oxide levels. Conclusion The combination of desloratadine and montelukast provides inhibition that is superior to both monotherapies on the early and the late airway responses to inhaled allergen in people with mild atopic asthma.