This programme of research uses choice test methodologies to quantify hungry broiler breeder chickens’ preferences for qualitative or quantitative dietary restriction. It begins with an outline of quantitative dietary restriction, its severity and welfare implications before discussing methods of qualitative feed restriction and the difficulties ascertaining whether it represents a welfare improvement. Chapter two reviews the factors affecting diet preferences and discusses implications for feed restricted broiler breeder diet preferences. Chapter three outlines the use of a closed economy T-maze task to quantity the diet preferences of feed restricted broiler breeders. It concludes that broiler breeders can learn a food versus no food task but find it very difficult to learn a task in which both of the options are rewarded with food and this impeded diet preference quantification. Chapter four demonstrates that severity of feed restriction underlies these difficulties in learning. In Chapter five, a conditioned place preference task to identify the effects of diets on affective state (hunger versus satiety) is reported. A method validation group demonstrated that broilers show a state dependent preference for an environment associated with ad libitum access to food. However, birds failed to show a preference between an environment associated with quantitative dietary restriction and one associated with qualitative dietary restriction. Chapter six applies state- dependent learning (SDL) to quantifying the satiating effects of quantitative and qualitative dietary restriction. However, a validation group suggested that SDL preferences were probably an artefact of the test rather than a genuine state-led preference. Finally, the overall conclusion that no evidence was found that broiler breeders want, or that their welfare is improved by, qualitative feed restriction was drawn. However, the conditions under which a preference was reliably observed and the presence of hunger – state dependent effects on learning and expression of learnt preferences complicates the interpretation of any findings. Recommendations for further research are highlighted.

Purpose: Adults with stuttering (AWS) commonly demonstrate verbal avoidance behaviours as a result of speech-related anxiety. This can result in an experience of ‘communication restriction’. By nature, verbal avoidance and communication restriction are difficult to evaluate objectively, and existing evidence consists primarily of self-report data from qualitative interviews. However, recent preliminary evidence indicates the potential utility of systemic functional linguistics (SFL; Halliday, 1985) to this area of research. The SFL framework provides quantitative analyses for the objective examination of language use in sociolinguistic contexts. Recent data also suggest that the confrontation naming paradigm may be a second possible means for quantitatively evaluating aspects of functional linguistic behaviour in AWS. The purpose of the present study was to identify specific patterns of conversational language and confrontation naming behaviour in AWS using an objective methodology, and to explore these behaviours within the context of stuttering intervention and with reference to the experience of communication restriction. Method: Twenty AWS (14 males, 6 females) and 20 matched controls (AWNS), aged between 16 and 56 years, were recruited for this study. All participants were native speakers of English with no cognitive, language, motor speech, or hearing impairment (with the exception of stuttering in AWS). All participants completed: (a) self-rating scales of general and communication-related attitudes and anxiety; (b) the UC Picture ID (O’Beirne, 2011) picture naming task, designed to objectively evaluate verbal avoidance behaviour; and (c) 10 minutes of spontaneous conversation with an examiner, loosely structured around a range of set topics. For the AWS participants, these procedures were completed pre- and post-attendance at either the Naturalness Intensive Programme in Christchurch, New Zealand (NZ), or the Intensive Stuttering Clinic (Blomgren, 2009) in Salt Lake City, USA (US). All conversational samples were analysed using both conventional and SFL-based analyses. Specifically, the quantity and complexity of verbal output, as well as the frequency of use of transitivity, modality, appraisal, and thematic resources, were examined. To identify group differences on all measures between AWNS and AWS at both pre- and post-treatment, two-tailed independent samples t-tests and Mann-Whitney U-tests were conducted. To compare the performance of AWS between pre- and post-treatment, two-tailed paired t-tests and Wilcoxon matched pairs signed ranks tests were used. Group comparisons were conducted for the full participant group, as well as separately for the NZ and US subgroups. Pearson correlation matrices were also constructed, to identify linear relationships between measures. Correlations between conventional and SFL analyses of linguistic behaviour were of particular interest. Results: Group differences for each subgroup were generally consistent with those for the full participant group. (a) AWS demonstrated higher social anxiety than AWNS at pre-treatment, but self-reported anxiety levels and stuttering impact decreased following treatment. (b) No differences were found across comparisons for confrontation naming performance on the UC Picture ID task. (c) In conversation, AWS produced consistently less language than AWNS, and produced less complex language than AWNS at pre-treatment, as shown by conventional and SFL indices. Specific SFL measures revealed fewer politeness-marking modal operators, more frequent comment adjuncts, and reduced expression of appraisal in the spontaneous language of AWS. Improvements in most of these areas were seen following treatment. The results of the correlational analyses showed that self-report scale outcomes were not linearly correlated to actual performance on any linguistic measures. However, positive correlations were observed between basic linguistic indices (i.e., language productivity and complexity) from the conventional and SFL approaches. An interesting negative correlation between language productivity and frequency of use of comment adjuncts was also seen. Conclusions: The current study extends available preliminary evidence on language use in AWS. Linguistic patterns identified in the conversational language of AWS suggest a reduced openness to interpersonal engagement within communication exchanges, which may restrict the experience of such exchanges. The data indicate that conventional and SFL analyses are interchangeable at a basic level, but also exemplify the unique utility of the SFL framework for examining specific aspects of language functionality within social context. Although AWS and AWNS were not found to differ in performance on the UC Picture ID task, the observations provide insight into the conditions under which verbal avoidance behaviours may be prone to occurring. Finally, the lack of straightforward correlations between self-reported anxiety and avoidance on the one hand, and various linguistic-behavioural indicators on the other, highlights the importance of a multidimensional, holistic approach to clinical stuttering evaluation.

To evaluate the impact of reduced truck tire pressure on strain response of low volume spring-restricted roads, research was conducted on two instrumented pavement sections in Manitoba, Canada. Tire pressure control systems tests were carried out at the sections in spring and fall 2009. Measured maximum tensile strain at the bottom of asphalt layer decreased by 15-20% when tire pressure was reduced by 50%. Measured strain at the bottom of asphalt layer in fall is about 50% less than in spring. The effects of gauge orientation, truck speed, and tire offset from the strain gauge were also analyzed. A finite element model with static load was developed and verified. The bearing capacity is lower in spring than in normal condition for flexible pavements subject to deep frost action. Reduced tire pressure is effective to reduce bottom up failure of the pavement, and is less effective to prevent rutting.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [111]-128).

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 205-207). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 77-85). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 205-207). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 77-85). Also available on the Internet.

Fetal growth in utero depends on nutrient and oxygen reaching the fetus through the uterine and placental microcirculations, both undergoing massive expansion during pregnancy. Aberrations of the placental vasculature are associated with Intrauterine Growth Restriction (IUGR), a common pathological outcome of pregnancy; however, the cellular components responsible for vessel formation in the placenta and the uterus remain unknown. Endothelial Progenitor Cells (EPC) are a group of morphologically and functionally varied bone marrow derived vasculogenic cell types, divided into two major subsets: (i) Circulating Angiogenic Cells (CACs), which promote vessel formation by interfering with the extracellular matrix and (ii) Endothelial Colony Forming Cells (ECFCs), which provide the source for new endothelium. This role has been demonstrated in pathophysiological studies, but not in normal physiological events in vivo. Fetal ECFCs are more proficient than their adult counterparts, but it is unclear in what specific fetal or maternal physiological situations fetal ECFCs are involved. Based upon these considerations, it was hypothesised that: (i) fetal-derived ECFCs play a role in placental vasculogenesis, (ii) these cells transmigrate the placenta and home to loci of vessel formation in the pregnant uterus, and that (iii) intrinsic alterations in their capabilities are associated with fetal growth restriction during intrauterine life. To support these hypotheses the following experiments were performed;(i) EPCs in blood from pairs of human umbilical arteries and veins were counted by flow cytometry. Numbers of EPCs in these samples showed an arterio-venous gradient suggesting their placental sequestration. Furthermore, ECFCs were isolated from human umbilical blood using established culture techniques. Labelled human fetal ECFCs were transplanted into the circulation of murine fetuses using an ultrasound-guided intra-cardiac injection. Using a fluorescent imager and microscopy these cells were shown to home to the murine placenta and participate in vasculogenesis.(ii) Male mice ubiquitously expressing eGFP were crossbred with native females, and fetal (eGFP-positive) endothelial-like cells integrated into the uterine microvasculature. Human fetal ECFCs injected into murine fetuses were shown to migrate to the maternal uterus and became functionally involved with the microvasculature. In humans, microvessels were isolated from uterine biopsies of mothers with male offspring. Copies of the male specific SRY gene (quantified by RT-QPCR) indicated that cells of fetal origin constituted 12% of the endothelium in these vessels. In cross-sections, hybridisation of the Y-chromosome demonstrated the presence of fetal cells in the maternal endothelium of the human uterus. (iii) Using flow cytometry, fewer EPCs were defined within the peripheral circulation of growth-restricted babies. Functional assays showed that ECFCs derived from these growth-restricted cases had intrinsically impaired proliferation, migration, matrix-metalloproteinase (MMP-2) production, and generated fewer blood vessels in a murine vasculogenic bioassay. These results demonstrated the vasculogenic capacity of human fetal ECFCs in vivo and established them as key players in human placental vasculogenesis and uterine vessel expansion. Notably, these results also showed a link between impaired function of fetal ECFCs and IUGR, which is associated with increased cardiovascular risk of both the fetus as an adult, and mother in later life. From these findings it could be speculated, that intrinsic changes in ECFC-biology may be the causative link between IUGR and fetal and maternal cardiovascular susceptibility. Insight into these processes may contribute to early diagnosis, prevention and treatment of IUGR and associated conditions.

Pregnancy complications such as fetal growth restriction (FGR) are often attributed to poor uteroplacental blood flow, but the risk of systemic side-effects hinders therapeutic intervention. We have utilised novel placental-specific homing peptides to overcome this and have conjugated these to biocompatible liposomes. Peptide-conjugated liposomes were found to selectively bind to the outer syncytiotrophoblast layer of the human placenta and to the uteroplacental vasculature and labyrinth region of the mouse placenta. The novel vasodilator SE175 was selected as a nitric oxide donor with a favourable stability and release profile, to encapsulate in peptide-conjugated liposomes in an attempt to restore impaired uteroplacental blood flow in a mouse model of FGR, the endothelial nitric oxide synthase knockout mouse. Liposomes containing SE175 or PBS were prepared by lipid film hydration and targeting peptides coupled to the liposomal surface. Vehicle control, free SE175, PBS- or SE175-containing liposomes were intravenously injected on embryonic (E) days 11.5, 13.5, 15.5 and 17.5. Animals were sacrificed at E18.5 and fetal and placental weights recorded. Targeted delivery of SE175 significantly increased fetal weight compared to vehicle control but no other treatment groups, whilst significantly decreasing placental weight, indicating improved placental efficiency. Treatment was well tolerated, having no impact on litter size or resorptions. Targeted delivery of SE175, but no other treatment group, reduced a marker of lipid peroxidation in the placenta, indicating a reduction in oxidative stress. These data suggest that selective delivery of SE175 to the uteroplacental vasculature in peptide decorated liposomes may represent a novel treatment for FGR.