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Wood density and fibre morphology of Pinus caribaea var. hondurensis Barrett and Golfari from Fiji were studied in relation to pulp properties. Densitometry and anatomical measurement were examined using billets taken from a sub-sample of 20 12-13 year old trees, chosen as representative of the density range observed in a first sample of 120 trees. Pulping properties were examined at the Tropical Products Institute, London. Considerable differences between trees were found in all characteristics examined and all characteristics showed fairly marked tree to tree variation in development patterns in a radial direction though differences along the stem were small. Between ring differences for ring width, density, cell wall thickness and cell wall percentage were considerable but cell lumen width and cell diameter were fairly constant between rings. Tree morphological characteristics cannot be used for estimation of whole tree values for any of the features studied. Whole tree values for wood characteristics can be accurately predicted from samples taken at 5% height level. Characteristic patterns of wood density distribution classes and tracheid cross sectional dimension classes were found, resembling chi-squared, binomial and bimodal curves. Wood properties could be used to predict pulp yield percentage and tear factor accurately by simple regression, less precise estimates could be obtained in this way, for burst factor and breaking length, which were best indicated by cell wall thickness. The best indicators of variation in pulp total yield percentage were chemical properties. Density was the best indicator of tear factor whilst cell wall thickness was the most important factor in explaining burst factor and breaking length. Growth rate showed negative correlation with wood density; trees of lower density produce paper of a strength generally at least equal to that obtained with higher density trees, though tear factor was lower. Thus the selection of trees for fast growth rate is suggested as the most profitable course. The most desirable selection criteria are listed.

This paper is primarily concerned with developing the theory of real-valued functions of bounded variation and those ideas which are closely related to this main topic. In addition to this, some emphasis has been placed on the relationship of the theory of functions of bounded variation to specific areas of analysis. In particular, integration theory has been chosen as the vehicle to demonstrate this connection.

The frequency of variations in nine morphological features of the cervical column in a South African (S.A.) black and white example of human skeletons was investigated to determine whether there Was a greater degree of morphological variability in the black as compared with the white sample. These findings were compared with other population groups. Intertribal, sex and side differences were examined, The possible aetiology of these variations was explored. [Abbreviated abstract. Open document to view full version] / GR 2016

Prenatal stress (PNS) has been shown to affect a range of different modalities, like stress responsiveness and affective traits in both animals and humans. Previously, Dr Paula Brunton’s lab has used a novel model of ethologically relevant prenatal social stress and had shown increased stress responsiveness in both first generation (F1) PNS males and females and increased anxiety-like trait in males, together with corresponding changes in mRNA expression for corticotrophin releasing hormone (Crh) and its receptors. The first aim on this project was to further explore the phenotype of PNS offspring created using this model in social context. F1 PNS females, but not males, displayed an impairment in social memory in comparison to control females, which was supported by lower vasopressin receptor type 1a (Avpr1a) mRNA expression in the anterior part of lateral septum and bed nucleus of stria terminalis. Acute stress exposure immediately prior to the social memory test, impaired social memory in control males and females, but had no effect in PNS males and markedly improved performance in PNS females. This facilitated learning in the PNS females was supported by the finding of higher Avpr1a mRNA expression in both target regions in the brain. Finally, olfactory memory for social but not non-social odours was also impaired in PNS females, compared to control females, indicating that deficits in social memory in PNS females are specific to social odours and not in the detection and/or processing of all odours. It has been shown previously that phenotypes observed in PNS animals can also be seen following disrupted maternal care in the early post-partum period and that stress can affect maternal behaviour. To investigate this possibility in the current model a maternal behaviour observation protocol was developed. Dams were observed during the first postnatal week, three times/day in 90 min blocks. Stressed dams showed an increase in pup-directed behaviours, together with an increase in arched back nursing specifically, compared to control dams. Furthermore, studies have shown that maternal behaviour patterns can be transferred from mother to daughters, therefore this possibility was also investigated here. There were no differences in maternal behaviour between F1 control and F1 PNS dams. The maternal behaviour experiment for the F1 PNS dams created a unique opportunity to study their offspring (F2). F2 PNS rats had lower body weights than their control counterparts throughout their lifetimes, while not differing significantly in their calorie intake. Increased anxiety-like behaviour was also observed in both the F2 males and females (but only during proestrous and estrous stages of their cycle). These changes were supported in males by increased Crh and Crh receptor type 1 and decreased Crh receptor type 2 mRNA expression in discrete regions of the amygdala. Furthermore, F2 PNS females exhibited exaggerated, and males attenuated ACTH and corticosterone secretion in response to acute stress, compared with controls. The reduced stress response in F2 PNS males was supported by higher glucocorticoid receptor (GR, Nr3c1) mRNA expression in field CA1 of hippocampus. In F2 PNS females, increased stress responses were associated with increased Crh and Avp mRNA expression in the medial parvocellular division of the paraventricular nucleus of the hypothalamus and lower basal Nr3c1 and mineralocorticoid receptor (MR, Nr3c2) mRNA expression in the hippocampus. As increased stress and anxiety-like responses have been linked to a depressive phenotype that possibility was also investigated. No changes were found in either sucrose preference or floating/swimming behaviour in the forced swim test between the F2 PNS and control rats, in either sex. Finally, the variation in individual stress responsiveness and anxiety-like trait and the relationship between these phenotypes was investigated in an outbred male Sprague Dawley population. It was found that three of the most commonly used anxiety tests: open field test, light dark box and elevated plus maze do not correlate as well with each other as could be expected. Secondly plasma corticosterone concentrations 30min after the onset of acute restraint stress were positively correlated with the amount of time the rats spent in the anxiogenic environments, showing perhaps counter-intuitively, that the higher the stress responses the less anxious the male rat is. The behavioural tests were also used as a selection procedure to compare gene expression by microarray in the amygdala of high and low anxious rats and hypothalamus of high and low stress-responsive rats. To summarise, stress during pregnancy has profound effects on the dams’ immediate maternal behaviour, as well as neuroendocrine and behavioural effects in both the F1 and F2 offspring. Furthermore, there is evidence of inter-individual variation in stress responsiveness and anxiety-like behaviour in an outbred rat population. This data could lead to further understanding of the origins of inter-individual variation and appreciation of the effect of stress throughout the life course.

1. I have described a population of children and young adults with asthma in primary and secondary care, in terms of relevant history, medication use and exacerbations. 2. My thesis presents observations reported for the first time that asthmatic children and young adults homozygous for the Arg16 allele on the ß2 adrenergic receptor gene (ADRB2), on frequent doses of on demand short-acting ß2-agonists are at greater risk of asthma exacerbations.I have shown an increase in the risk of exacerbations per copy of Arg16 allele in children and young adults with asthma on the regular long-acting ß2-agonist salmeterol. 4. I have shown that there is an increase in risk of exacerbations per copy of Arg16 allele in children and young adults with asthma on frequent (once daily or more) as required doses of inhaled salbutamol. This effect is not observed on participants with asthma who are not exposed to ß2-agonist on a daily basis. 5. I have shown that the Arg16Arg variant status may be associated with worse airway obstruction, as measured by the FEV1/FVC ratio.6. I have shown that the individuals with FLG null alleles have a significantly increased risk of exacerbations requiring hospital admissions, courses of oral steroids, or experiencing school absences

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Large dense structures like DRAMs (Dynamic Random Access Memory) are particularly susceptible to process variation, which can lead to variable latencies in different memory arrays. However, very little work exists on variation studies in DRAMs. This is due to the fact that DRAMs were traditionally placed off-chip and their latency changes due to process variation did not impact the overall processor performance. However, emerging technology trends like three-dimensional integration, use of sophisticated memory controllers, and continued scaling of technology node, substantially reduce DRAM access latency. Hence, future technology nodes will see widespread adoption of embedded DRAMs. This makes process variation a critical upcoming challenge in DRAMs that must be addressed in current and forthcoming technology generations. In this paper, techniques for modeling the effect of random, as well as spatial variation, in large DRAM array structures are presented. Sensitivity-based gate level process variation models combined with statistical timing analysis are used to estimate the impact of process variation on the DRAM performance and leakage power. A simulated annealing-based Vth assignment algorithm using adaptive body biasing is proposed in this thesis to improve the yield of DRAM structures. By applying the algorithm on a 1GB DRAM array, an average of 14.66% improvement in the DRAM yield is obtained.

As VLSI technology moves into the Ultra-Deep Sub-Micron (UDSM) era, manufacturing variations, power supply noise and temperature variations greatly affect the performance and yield of VLSI circuits. Clock Distribution Network (CDN), which is one of the biggest and most important nets in any synchronous VLSI chip, is especially sensitive to these variations. To address this problem variability-aware analysis and optimization techniques for VLSI circuits are needed. In the first part of this thesis an analytical bound for the unwanted skew due to interconnect variation is established. Experimental results show that this bound is safer, tighter and computationally faster than existing approaches. This bound could be used in variation-aware clock tree synthesis.The second part of the thesis deals with optimizing a given clock tree to minimize the unwanted skew variations. Non-tree CDNs have been recognized as a promising approach to overcome the variation problem. We propose a novel non-tree CDN obtained by adding cross links in an existing clock tree. We analyze the effect of the link insertion on clock skew variability and propose link insertion schemes. The non-tree CDNs so obtained are shown to be highly tolerant to skew variability with very little increase in total wire-length. This can be used in applications such as ASIC design where a significant increase in the total wire-length is unacceptable.

Linguistic research on adverbs has taken many forms: typological, morphological, syntactic, semantic and pragmatic. However, little work has been conducted on adverbs using the tools of quantitative sociolinguistics, and most of that work has focused solely on morphological variation of the -ly suffix. This work addresses the lacuna by examining two adverb phenomena using quantitative variationist methodology. Data come from two large, socially stratified, sociolinguistic corpora of vernacular English. The two corpora contain data collected in Ontario, Canada and in Northern England, and are comprised of the speech of over 150 speakers across all age groups. In the first case study, I examine a claim in usage guides (e.g., Swan 2001) that North American English widely permits pre-auxiliary adverbs in canonical, declarative sentences, while British English prohibits them unless accompanied by contrastive stress. As I show, the varietal differences in speech are not only minimal and unrelated to stress, but instead are highly circumscribed. In addition, I demonstrate that the positioning of adverbs observed here must involve post-syntactic processes. The second case study examines variability in the discourse adverb "actually" and several related adverbials (e.g., "really" and "in fact") and examines the path of grammaticalization (Traugott & Dasher 2002) in the two communities. I demonstrate that Canadians, regardless of sex or education level, prefer the more grammaticalized forms of "actually"; in the UK, the more grammaticalized use is less common, though some young men are leading a shift to the more grammaticalized pattern.