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One of the problems encountered in paper converting is caused by the occurrence of "baggy webs", which essentially is when the tension profile of the paper web is uneven. In an area with low tension the paper is longer, which results in bagginess. The baggy parts can not usually be stretched to even out the tension of the paper web in a converting machine, with the result that runnability problems are likely to occur. The aim of the work described in this thesis was to investigate three particular stages in papermaking, namely drying, calendering and storage, and rank them according to their propensity for inducing baggy webs. The focus was placed on investigating the effects of uneven moisture and grammage profiles on the machine-direction strain difference profile. The largest strain difference occurred when there were systematic thick streaks throughout a reel that formed ridges. Stress relaxation during storage then gave rise to a difference in strain of 0.14% when the ridge height was around 2-3 mm. Thickness variations due to variations in grammage is also a source of moisture variation. A difference in moisture of 5% in the calendering stage resulted in strain differences of about 0.05-0.08%. These strain differences resulted in creases being formed as early on as in the calender nip when differences in both grammage and moisture content were present. Most creases appeared when the moisture difference was 2-8%. The difference in grammage could be large without creases being formed when no differences in moisture content were present. A moisture difference of about 5-6% during drying resulted in a strain difference of 0.1% measured on isotropic samples. The moist area turned into a tight streak when the moisture difference appeared at moisture contents higher than 25%. At moisture contents lower than 20%, on the contrary, the moist area turned into a slack streak. The conclusion drawn is that papermakers should concentrate first and foremost on eliminating variations in grammage, especially if these are systematic. This would also eliminate some variations in moisture content, which would solve more problems.

Despite over a century of inquiry, the mechanisms that achieve the close matching of oxygen supply to demand during exercise remain elusive. It has been proposed that in addition to its role as the primary oxygen carrier, the red blood cell (RBC) functions as a roving oxygen sensor, linking the oxygen demand at the muscle with oxygen delivery via the circulation (Ellsworth et al. 1995). It is hypothesised that the RBC would release adenosine triphosphate (ATP) in proportion to the number of unoccupied binding sites on the haemoglobin molecule as it traverses regions of high oxygen demand such as the microcirculation of active skeletal muscle. ATP would then stimulate the release of vasodilatory substances from the endothelium which would diffuse to neighbouring vascular smooth muscle resulting in vasodilation and an increase in blood flow in accordance with the oxygen demand set by the muscle. The first step in establishing a role for this mechanism during exercise in humans is to determine whether ATP increases in the venous blood draining an active muscle bed. Based on the handful of published studies, there is an increase in ATP concentration in the femoral vein during knee extensor exercise. However the response has not been studied in other vascular beds in humans. As such, the main aim of this thesis was to measure the ATP response to dynamic handgrip exercise. Secondary aims were to determine whether the response was modified by hypoxia, and to provide information about the timing of the changes in ATP concentration during a bout of handgrip exercise. These questions were addressed in Studies 3 and 4. Because blood flow is central to this hypothesis, a substantial portion of this thesis was also associated with the measurement of forearm blood flow (FBF) using venous occlusion strain gauge plethysmography (VOSGP), and this was conducted in Studies 1 and 2. VOSGP is based on the assumption that with venous outflow prevented, any increase in limb volume is proportional to the rate of arterial inflow. The rate of arterial inflow is determined as the slope of the change in limb volume over time. The slope must be calculated over the initial linear portion of this relationship, when arterial inflow is unaffected by the inevitable rise in venous pressure associated with venous occlusion. VOSGP was initially used to measure blood flow at rest and in response to pharmacological interventions which produced only modest increases in arterial inflow (Joyner et al. 2001). However, measurement of the high rates of arterial inflow that occur with exercise may challenge the limits of this technique. Tschakovsky et al. (1995) reported a marked reduction in arterial inflow over the first four cardiac cycles during venous occlusion following static handgrip exercise that elevated blood flow to 22-24 mL/min/100mL. Only during the first cardiac cycle was arterial inflow unaffected by cuff inflation. As such, the window for measuring high rates of arterial inflow may be very brief. Therefore Study 1 aimed to determine whether blood flow could be measured using VOSGP across the range of arterial inflows that occur with dynamic handgrip exercise. Participants (n = 7) completed four, five-minute bouts of dynamic handgrip exercise at 15, 30, 45, and 60% of maximum voluntary contraction (MVC). FBF was measured using VOSGP at rest, and following five minutes of dynamic handgrip exercise. The slope of the change in limb volume was measured over the first one, two, three, and four consecutive cardiac cycles following the onset of occlusion. FBF was 2.5 ± 0.5 at rest, and 16.5 ± 4.9, 24.9 ± 9.4, 44.1 ± 22.0, and 57.8 ± 14.9 mL/min/100mL following five minutes of exercise at 15, 30, 45, and 60% MVC, respectively. At rest, arterial inflow decreased across the four cardiac cycles (P = 0.017 for the main effect), however post-hoc pairwise comparisons revealed no significant differences between any of the cardiac cycles. In contrast, the inclusion of two, three, or four cardiac cycles at 30 and 60% MVC, and three or four cardiac cycles at 15 and 45% MVC resulted in reductions in calculated arterial inflow compared with using the first cardiac cycle alone (P > 0.05). The inclusion of just two cardiac cycles resulted in a 9-26% reduction in calculated arterial inflow depending on the workload. This reduction was even more pronounced when three (19-40%) or four (26-50%) cardiac cycles were included. In conclusion, resting FBF can be calculated over at least four cardiac cycles during venous occlusion at rest. However, exercising FBF should be calculated from the first cardiac cycle only following dynamic handgrip exercise across the range of intensities used in this study. This extends the findings of Tschakovsky et al. (1995) who demonstrated this effect following handgrip exercise at a single intensity. Study 2 was designed to establish the FBF response to dynamic handgrip exercise, whether the workloads produced different blood flow responses, and to establish the within- and between-day reproducibility of FBF measured using VOSGP. In Part A (within-day reproducibility), participants (n = 7) completed three trials of dynamic handgrip exercise at four intensities (15, 30, 45, and 60% MVC), with each exercise trial separated by 10 minutes of rest. In Part B (between-day reproducibility) participants (n = 7) completed three trials of dynamic handgrip exercise at 15, 30, and 45% MVC on three separate days within a two week period. FBF was measured at rest, and each minute of exercise during brief (5-7 second) pauses in contractions. FBF response. FBF increased from rest at all workloads (P > 0.05), and then plateaued between Minutes 1 to 5 at the 15 and 30% MVC workloads and between Minutes 2 and 5 at the 45% workload (P > 0.05 for each minute compared to Minute 5). Too few participants completed the 60% workload to permit any statistical analysis. FBF reached values of 13.0 ± 2.0, 26.8 ± 8.4, 44.8 ± 14.9, and 52.9 ± 5.1 mL/min/100mL in the final minute of exercise at the 15, 30, 45, and 60% MVC workloads. FBF was different between the 15, 30, and 45% workloads by Minute 3 (P > 0.05). Reproducibility. The within-day test-retest reliability of exercising FBF was poor to moderate (ICC = 0.375-0.624) with individual coefficients of variation (CVs) ranging from 6-25%, 9-23%, and 9-31% for the 15, 30, and 45% MVC workloads, respectively. The between-day test-retest reliability for resting FBF was moderate (ICC = 0.644, P > 0.05; individual CVs between 1 and 31%). Between-day test-retest reliability for exercising FBF was poor to moderate (ICC = 0.381-0.614), with individual CVs ranging from 14-24%, 8-23%, and 6-18% for the 15, 30, and 45% workloads, respectively. It was concluded from this study that VOSGP provides adequately reproducible measurements to detect changes in FBF of the magnitude seen between workloads in this study. However, the variability in the measurement precludes its use when smaller differences are of interest. Based on the previous findings reporting an increase in ATP concentration during dynamic knee extensor exercise in the leg (Gonzalez-Alonso et al. 2002; Yegutkin et al. 2007), Study 3 was designed to determine whether ATP concentration increased in the venous effluent during dynamic handgrip exercise in the forearm. Since the deoxygenation of haemoglobin is a primary stimulus for ATP release from red blood cells, a further aim was to determine whether this response was augmented by systemic hypoxia. Participants (n = 6) completed four, five-minute bouts of dynamic handgrip exercise at 30, 45, 65, and 85% MVC under normoxia (inspired oxygen fraction = 0.21) and hypoxia (inspired oxygen fraction = 0.12). Blood samples for the determination of ATP concentration were drawn at rest and 180 seconds after the onset of exercise at each workload from a catheter inserted into a forearm vein. Venous plasma ATP concentration at rest was 0.28 ± 0.11 μM/L and remained unchanged during exercise at workloads up to 85% MVC (P > 0.05). Systemic hypoxia, sufficient to reduce arterial oxygen saturation to 83 ± 2%, also failed to alter the plasma ATP concentration (P = 0.148). The lack of a change in ATP concentration was unexpected but there are several possible explanations. It is possible, although unlikely, that ATP was not released in the forearm microcirculation. The previous demonstration that ATP increased in response to static handgrip exercise (Forrester and Lind 1969) would suggest that this was probably not the case. When considered in the context of the findings from Study 4, the most plausible explanation is that a less than optimal blood sampling site may have hindered the measurement of a change in ATP. The blood flow response at the onset of dynamic exercise in the forearm is at least biphasic; Phase 1 describes the immediate, large increase in blood flow within 2 seconds of the onset of exercise and is believed to be governed by mechanical factors whereas Phase 2 has a latency of ~20 seconds and describes a further, slower increase until blood flow reaches steady state (Saunders et al. 2005b). The temporal characteristics of Phase 2, along with the fact that blood flow during this phase is closely related to the metabolic rate of the muscle, suggest regulation by metabolic factors. Currently there is scant evidence detailing the time course of vasodilator release, although it is important to demonstrate that the release of a vasodilatory substance precedes the blood flow response it is proposed to influence (Delp 1999). ATP is released from red blood cells in proportion to the offloading of oxygen and a reduction in the oxygen content of venous blood draining a muscle bed occurs within 10 seconds of the onset of exercise. Thus the release of ATP should follow soon thereafter. As such, Study 4 was designed to determine whether ATP increased in the venous effluent of the forearm following 30 and 180 seconds of dynamic handgrip exercise at 45% MVC; and whether this increase corresponded with a decrease in venous oxygen content. Participants (n = 10) completed two bouts of dynamic handgrip exercise at 45% MVC; the first was one minute in duration, and the second was four minutes in duration. Venous blood samples for the determination of ATP and venous oxygen content were drawn at rest and during exercise from a catheter inserted in a retrograde manner into the median cubital vein. Arterialised samples for the estimation of arterial blood gases and ATP concentration were obtained from the non-exercising hand. ATP concentration in arterialised blood from the non-exercising arm was 0.79 ± 0.30 μM/L at rest and remained unchanged at both time points during exercise (P > 0.05). ATP concentration in the venous blood of the exercising arm increased from 0.60 ± 0.17 μM/L at rest to 1.04 ± 0.33 μM/L 30 seconds after the onset of exercise (P > 0.05), and remained at this higher level after 180 seconds (0.92 ± 0.26 μM/L, P > 0.05 versus rest). This corresponded with a decrease in venous oxygen content from 103 ± 23 mL/L at rest to 68 ± 16 mL/L 30 seconds after the onset of exercise (P > 0.05) and 76 ± 15 mL/L (P > 0.05 versus rest) 180 seconds into exercise. Furthermore, at 180 seconds of exercise, ATP concentration was moderately and inversely related to venous oxygen content (r = -0.651, p > 0.05). In conclusion, this study provides the first evidence that ATP concentration is increased in the blood draining the exercising forearm muscles in response to dynamic handgrip exercise. The finding that ATP concentration was increased just 30 seconds after the onset of exercise is also novel, and particularly interesting in the context of the recently reported dynamic response characteristics of the forearm blood flow response. In conclusion, the work contained within this thesis provides several important findings. The first study has provided evidence that measuring high rates of arterial inflow using VOSGP is possible, but that the window for making these measurements is small, probably as brief as a single cardiac cycle. The second study demonstrated that while the reproducibility of forearm blood flow measurements using VOSGP is poor, it is adequate to detect the large changes that occurred between workloads. However, VOSGP cannot be used to detect more modest differences. Common to both Study 3 and 4 was the measurement of ATP at rest, and 180 seconds after the onset of dynamic handgrip exercise at 45% MVC. The primary difference was the position of the catheter which was inserted in an antegrade manner in Study 3, and in a retrograde manner in Study 4. Since ATP was unchanged in Study 3 but increased under similar conditions in Study 4, it is likely that ATP was also released during exercise in Study 3, but that a less than optimal blood sampling site precluded its measurement. This illustrates the necessity to sample blood from as close as possible to the probable site of ATP release, the muscle microcirculation. The most important and novel findings from this body of work come from Study 4. This is the first study to demonstrate an increase in ATP concentration in the forearm in response to dynamic handgrip exercise. However, the most novel finding was that ATP concentration was elevated just 30 seconds after the onset of exercise. Such an early increase has not previously been reported during dynamic exercise in any vascular bed. This is an important finding since establishing the time course for the release of vasodilatory substances is critical to our understanding of the mechanisms that regulate blood flow during exercise.

The principal contribution of this dissertation is a theory of Strongly Orthotropic Continuum Mechanics that is derived entirely from an assertion of geometric strain indeterminacy. Implementable into the finite element method, it can resolve widespread kinematic misrepresentations and offer unique and purportedly exact strain-induced energies by removing the assumptions of strain tensor symmetry. This continuum theory births the proposal of a new class of physical tensors described as the Intrinsic Field Tensors capable of generalising the response of most classical mechanical metrics, a number of specialised formulations and the solutions shown to be kinematically intermediate. A series of numerical examples demonstrate Euclidean objectivity, material frame-indifference, patch test satisfaction, and agreement between the subsequent Material Principal Co-rotation and P??I??C decomposition methods that produce the intermediary stress/strain fields. The encompassing theory has wide applicability owing to its fundamental divergence from conventional mechanics, it offers non-trivial outcomes when applied to even very simple problems and its use of not the Eulerian, Lagrangian but the Intrinsic Frame generates previously unreported results in strongly orthotropic continua.

Barramundi (Lates calcarifer) aquaculture is expanding throughout Australia and the Asia-Pacific region. The Department of Primary Industries, Queensland have estimated that the production from this industry could reach $30 million per annum in Australia by 2010. However, current production is severely impeded by outbreaks of Streptococcus iniae, which causes a fatal septicaemia in barramundi. S. iniae is a Gram positive bacterium which infects both humans and fish and was first reported in Australia in the 1980s in Queensland, but has rapidly disseminated to other states in Australia (Western Australia, Northern Territory, South Australia). Globally, there appears to be little geographical restriction to the distribution of S. iniae and infection occurs in temperate, sub-tropical and tropical, marine and fresh water fish with no evidence of species specificity. Outbreaks have been reported in North America, Middle East, Europe and Asia-Pacific, including Australia, Indonesia, Malaysia, Korea, China, Taiwan and Japan. Understanding distribution and spread of S. iniae is confounded by a number of factors. Firstly, identification of S. iniae is not straightforward, thus isolates often remain ‘unidentified’, as this bacterium is not included in commercial databases. In other cases it is misidentified as other bacteria such as S.uberis, S. dysgalactiae subsp. equisimilis and S. anginosus. Furthermore, variability in phenotypic traits has led to difficulty in identifying isolates using standard commercial diagnostic kits. Additionally, there is tangible evidence of geographic diversity and endemism with strain variability having been reported from fish isolates in Japan, USA and Israel, and in human isolates from Canada, USA and SE Asia. Understanding strain diversity amongst S. iniae is critically important in terms of managing the disease. Ability to track routes of distribution of the pathogen in imported fish, including ornamentals and food fish has implications for better biosecurity. Perhaps most importantly, strain diversity has been reported as a cause of vaccine failure in trout in Israel and in barramundi in Northern Territory, Australia. To date, very little information exists on strain diversity in S. iniae and no research has been conducted on the diversity amongst Australian isolates within the barramundi industry. The aim of this thesis is to develop reliable methods for identification of differing strains of S. iniae and to investigate antigenic diversity in order to better inform both vaccine design and biosecurity procedures with which to manage this important disease in Australia and globally. To achieve this, a collection of more than 100 isolates from Australia and throughout the world has been created and stored at the University of Queensland. In the first chapter of my thesis, routine confirmatory diagnosis using amplification of the lactate oxidase gene was performed to support biochemical and physiological identification provided by the supplying laboratories and veterinarians. During this initial screen, two important discoveries were made. Firstly, S. iniae isolates can be divided into two groups based on the different sizes of PCR product obtained, 869 bp (now named Type 1) and 921 bp (now named Type 2). This difference was only found in isolates from Northern Territory, Australia. In light of this, identity was further confirmed by the results of partial sequencing of the 16S rRNA gene with the 530F primer and submission to the BLAST server (http://www.ncbi.nlm.nih.gov/BLAST), which returned identities of 100% to S. iniae ATCC 29178. Sequence analysis of the lctO gene in isolates representing both the normal (lctO type 1) and higher molecular weight (lctO type 2) revealed that there is an insertion of 51 bp of repeat sequence in lctO type 2. Apart from the insertion sequence found in the 3' end of the gene in some isolates, three nucleotides in positions 211-213, not previously detected when the gene was described previously, resulted in an inserted valine residue in the translated product from all isolates. I also note an apparent error in the primary sequence and translation of the GenBank sequence (Y07622). This is likely to be due to an inserted C nucleotide at position 1148 at the far 3’ end of the gene sequence (inside the LOX-1, LOX-2 priming region) that has altered the reading frame. This means that the expected PCR product size of 870 bp is incorrect and is actually 869 bp. To determine the phenotypic relevance of the variation in lox gene product size, the lactate oxidase enzyme was extracted from cell lysates and assayed for activity. The two variant genes were each cloned and expressed in E. coli. Lactate oxidase enzyme activity also showed that there were differences in enzyme activity between the two gene products with strains expressing the higher molecular weight enzyme variant exhibiting higher enzyme activity. This suggests that positive selection may apply in favour of the larger gene in situations where lactate is the most readily available carbon source. However, no variation was detected in the lactate permease gene lctP, for any of the strains analysed. Whilst there was no difference in the Minimum Inhibitory Concentration Test (MIC) using different concentration of lactate there were differences detected in the growth rate of QMA0165 and QMA0177. Significant inhibition on growth rate of QMA0165 was detected with a 0.3% and 0.5% of lactate while there was no significant inhibition in QMA0177 with the same concentration. Prediction on three dimensional protein structure using PyMol based on Aerococcus viridans 3-D protein structure showed that there was an additional loop in lctO type 2 which suggested that it might play a role in enhancing enzyme activity of the binding site. The environment in barramundi farms in Northern Territory where the lctO type 2 isolates were isolated has 9 metre tides resulting in water flows in excess of 3km/h. It is likely that the resulting enforced swimming of the fish host has led to selection and maintenance of a gene encoding the higher efficiency enzyme in S. iniae. As diversity has led to reported vaccine failure in Israel, and antigenic diversity has been recorded in Japan and in isolates from the USA, the second data chapter of this thesis explores surface antigenic diversity of Australian S. iniae isolates from barramundi using a whole cell ELISA using a suite of antibodies raised in barramundi against four S. inaie isolates from differing habitats (freshwater and marine) and states (Western Australia and Queensland) in Australia. Forty-one isolates predominantly from farmed fish throughout Australia between 1995 and 2006 were serotyped and compared with reference isolates from the USA and Canada. Multiple serotypes were identified using polyclonal sera raised in barramundi against four different Australian S. iniae isolates i.e. anti QMA0072 (Queensland), anti QMA0074 (Queensland), anti QMA0083 (Western Australia) and anti QMA0087 (Western Australia). Different serotypes were often isolated from the same sites either simultaneously or within short time periods, indicating potential coexistence of multiple isolates in a particular geographic location or habitat. Electrophoretic profiles of whole cell proteins and integral membrane proteins were similar amongst isolates when analysed by SDS- PAGE, regardless of serotype. The results presented here suggest that surface serotypic variability of S. iniae is complex and multifactorial involving capsular carbohydrate and some surface proteins. As raising consistent antiserum in barramundi is almost impossible, and rabbit antisera invariably recognise more epitopes than teleost fish, a more consistent molecular method of typing was investigated in the third data chapter. In this chapter, the whole genome of S. iniae was digested using SmaI and separated using Pulsed Field Gel Electrophoresis (PFGE). Twenty four isolates representing different geographical origin and host were analysed using this method. Reference isolates from dolphins, fish and humans were obtained from the Centers for Disease Control for comparison. PFGE profiles indicated at least 4 distinct groups amongst the Australian isolates, but these did not correlate with surface serotype. Interestingly, whilst there have been no reports of human cases of S. iniae infection in Australia, many of the isolates examined had closely related PFGE profile with reference human isolates from USA and Canada, but were markedly different from the type isolates isolated from dolphins. One of the major difficulties associated with PFGE is between lab variability, hence the requirement for inclusion of large numbers of reference isolates on each gel. Recently, multilocus sequence typing (MLST) has been developed for epidemiological studies in a variety of human pathogens. MLST is based on sequencing of 8 ubiquitous housekeeping genes, genes which evolve slowly, allowing clustering of isolates. As sequencing is consistent between laboratories, results can be posted on a website and compared internationally without requiring transfer of strains overseas. The fourth data chapter in my thesis develops for the first time an MLST scheme for S. iniae. Primers for eight housekeeping genes were designed and annealing temperature for amplification were optimized. The selected housekeeping genes were: adhP (Alcohol dehydrogenase), pheS (Phenylalanyl tRNA syhthetase), atr (Amino acid transporter), glnA (Glutamine synthetase), sdhA (Serine dehydrogenase), glcK (Glucose kinase) and tkt (Transketolase). However, glnA was dropped from the analysis because of the inconsistent PCR product. Thirty seven isolates were selected representing the Australian isolates and other international isolates from United States, Canada, Israel, Thailand, Reunion Island with different hosts i.e. Amazon freshwater dolphin, human, flying fox and different species of fish (Channa striata, Oncorhynchus mykiss and Lates calcarifer). As there is no database available for S. iniae in the MLST database yet, only limited isolates from the global collection that can be analysed with the Australian isolates. The present study found that MLST results are less discriminative when compared to PFGE, but were very useful in pinpointing origin to a particular country, perhaps indicating little transfer of isolates between nations. MLST grouped together Australian, Thailand (QMA0187 and QMA0190), human isolates from Canada and USA regardless the geographic origin (QMA0130, QMA0133 and QMA0137) and also fish isolate from Canada (QMA0139). The similarity of the human isolates with the Australian isolates supporting PFGE results, which had a similar SmaI PFGE profiles to many of the fish isolates from Australia. However, MLST managed to distinguish isolates QMA0140 (dolphin/ USA), QMA0141 (dolphin/ USA), QMA0136 (human/ USA) and other international isolates from Israel (QMA0186 and QMA0188), Reunion Island (QMA0189). Despite the degree of heterogeneity in other methods used (serotyping, PFGE), MLST method showed a high homogeneity amongst S. iniae from Australia, perhaps reflecting the slow evolution of these genes and no accidental import of isolates. During the 12 years of isolates covered by our strain collection, there would appear to have been no evolution of these highly conserved genes within Australia. The variation in serotype within a single Sequence Type showed that there may be frequent horizontal gene transfer, or more rapid evolution of genes involved in synthesis and transport of capsular polysaccharide or other surface features. Moreover, the PFGE results indicate that there is more genetic plasticity in amongst the genome of S. iniae than indicated by then MLST. In order to gain a more discriminative epidemiological perspective of S. iniae, the results presented in this thesis suggest combination of different typing methods such as PFGE and MLST, with the latter providing an accurate means of determining nation of origin of strains (and therefore of great potential for biosecurity purposes) whilst PFGE may provide better discrimination of movement of local isolates within Australia.

[Truncated abstract] Characterising the behaviour of calcareous sediments that possess some degree of bonding between their constituents has attracted worldwide research interest in recent years. Although many recent studies have made significant contributions in delineating the behaviour of these sediments, there is still paucity of information particularly on the cyclic behaviour of cemented calcareous soils. This thesis describes in detail the characteristic features of cemented calcareous soils and proposes methods for characterising their cyclic behaviour. Two different calcareous soils Goodwyn (GW) and Ledge Point (LP) soils representing extreme depositional environments were examined in this study. Artificially cemented sample were created using the CIPS (Calcite Insitu Precipitation Systems) technique, considering its superiority over other most commonly available cementation techniques in replicating the natural pattern of cementation, and the behaviour of natural calcarenite under monotonic loading conditions. The experimental program involved triaxial testing of both uncemented and calcite-cemented calcareous soils under different loading conditions, i.e. isotropic compression tests to high-pressure (16 MPa), monotonic shearing tests, undrained cyclic shearing tests and undrained monotonic post-cyclic shearing tests. Significant emphasis has been placed on the cyclic behaviour of these soils. Internal submersible LDVTs were used for the accurate and continuous measurement of strain down to about 10-5

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 166-174).

Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 166-174). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 144-155).

Η Φυλλιτική-Χαλαζιτική ενότητα αποτελεί τμήμα των Εξωτερικών Ελληνίδων και έχει υποστεί μεταμόρφωση σε συνθήκες υψηλής πίεσης. Στην Κεντρική Κρήτη εμφανίζεται κυρίως στο βόρειο τμήμα του παραθύρου των Ταλαίων ορέων. Σκοπός της διπλωματικής εργασίας είναι να προσδιοριστεί η γεωμετρία του τριαξονικού ελλειψοειδούς της παραμόρφωσης και το ποσό της παραμόρφωσης στη Φυλλιτική-Χαλαζιτική ενότητα. Για το σκοπό αυτό συλλέχθηκαν 18 προσανατολισμένα δείγματα χαλαζιακής σύστασης και μετρήθηκαν ελλειπτικοί δείκτες της παραμόρφωσης σε δύο κάθετες μεταξύ τους τομές από κάθε δείγμα. Τα στοιχεία φανερώνουν ότι κατά την πλαστική φάση παραμόρφωσης D1 τα πετρώματα της Φυλλιτικής-Χαλαζιτικής ενότητας παραμορφώθηκαν κυρίως σε συνθήκες πλάτυνσης και σε μικρότερο βαθμό σε συνθήκες επίπεδης παραμόρφωσης. Επιπρόσθετα το ποσό της παραμόρφωσης έχει μια συστηματική και μη γραμμική αύξηση σε σχέση με την απόσταση από την επώθηση βάσης, ενώ ο τύπος του τριαξονικού ελλειψοειδούς δε συνδέεται με τη δομική θέση των δειγμάτων. / The Phyllite-Quartzite (PQ) unit is a part of the External Hellenides and has been subjected to a high pressure metamorphism. In Central Crete PQ unit mainly appears in the northern part of the Talaia window. The aim of this study is to determine the strain ellipsoid geometry and the intensity of deformation in the PQ unit. To do so 18 quartz-rich samples were collected, in which elliptical strain indicators were measured in two mutually perpendicular cross sections. Measurements show that during the D1 phase of the ductile deformation, rocks of the PQ unit were deformed mainly by flattening and secondary by plane strain conditions. Additionally, the amount of deformation shows systematic and non-linear increase relative to the distance of the Basal thrust while the type of strain ellipsoid is not related to the structural position of the samples in the PQ.