Local displacement efficiency in miscible floods is significantly affected by mixing taking place in the medium. Laboratory experiments usually measure flow-averaged ("cup mixed") effluent concentration histories. The core-scale averaged mixing, termed as dispersion, is used to quantify mixing in flow through porous media. The dispersion coefficient has the contributions of convective spreading and diffusion lumped together. Despite decades of research there remain questions about the nature and origin of dispersion. The main objective of this research is to understand the basic physics of solute transport and mixing at the pore scale and to use this information to explain core-scale mixing behavior (dispersion). We use two different approaches to study the interaction between convective spreading and diffusion for a range of flow conditions and the influence of their interaction on dispersion. In the first approach, we perform a direct numerical simulation of pore scale solute transport (by solving the Navier Stokes and convection diffusion equations) in a surrogate pore space. The second approach tracks movement of solute particles through a network model that is physically representative of real granular material. The first approach is useful in direct visualization of mixing in pore space whereas the second approach helps quantify the effect of pore scale process on core scale mixing (dispersion). Mixing in porous media results from interaction between convective spreading and molecular diffusion. The converging-diverging flow around sand grains causes the solute front to stretch, split and rejoin. In this process the area of contact between regions of high and low solute concentrations increases by an order of magnitude. Diffusion tends to reduce local variations in solute concentration inside the pore body. If the fluid velocity is small, diffusion is able to homogenize the solute concentration inside each pore. On the other hand, in the limit of very large fluid velocity (or no diffusion) local mixing because of diffusion tends to zero and dispersion is entirely caused by convective spreading. Flow reversal provides insights about mixing mechanisms in flow through porous media. For purely convective transport, upon flow reversal solute particles retrace their path to the inlet. Convective spreading cancels and echo dispersion is zero. Diffusion, even though small in magnitude, causes local mixing and makes dispersion in porous media irreversible. Echo dispersion in porous media is far greater than diffusion and as large as forward (transmission) dispersion. In the second approach, we study dispersion in porous media by tracking movement of a swarm of solute particles through a physically representative network model. We developed deterministic rules to trace paths of solute particles through the network. These rules yield flow streamlines through the network comparable to those obtained from a full solution of Stokes' equation. In the absence of diffusion the paths of all solute particles are completely determined and reversible. We track the movement of solute particles on these paths to investigate dispersion caused by purely convective spreading at the pore scale. Then we superimpose diffusion and study its influence on dispersion. In this way we obtain for the first time an unequivocal assessment of the roles of convective spreading and diffusion in hydrodynamic dispersion through porous media. Alternative particle tracking algorithms that use a probabilistic choice of an out-flowing throat at a pore fail to quantify convective spreading accurately. For Fickian behavior of dispersion it is essential that all solute particles encounter a wide range of independent (and identically distributed) velocities. If plug flow occurs in the pore throats a solute particle can encounter a wide range of independent velocities because of velocity differences in pore throats and randomness of pore structure. Plug flow leads to a purely convective spreading that is asymptotically Fickian. Diffusion superimposed on plug flow acts independently of convective spreading causing dispersion to be simply the sum of convective spreading and diffusion. In plug flow hydrodynamic dispersion varies linearly with the pore-scale Peclet number. For a more realistic parabolic velocity profile in pore throats particles near the solid surface of the medium do not have independent velocities. Now purely convective spreading is non-Fickian. When diffusion is non-zero, solute particles can move away from the low velocity region near the solid surface into the main flow stream and subsequently dispersion again becomes asymptotically Fickian. Now dispersion is the result of an interaction between convection and diffusion and it results in a weak nonlinear dependence of dispersion on Peclet number. The dispersion coefficients predicted by particle tracking through the network are in excellent agreement with the literature experimental data. We conclude that the essential phenomena giving rise to hydrodynamic dispersion observed in porous media are (i) stream splitting of the solute front at every pore, thus causing independence of particle velocities purely by convection, (ii) a velocity gradient within throats and (iii) diffusion. Taylor's dispersion in a capillary tube accounts for only the second and third of these phenomena, yielding a quadratic dependence of dispersion on Peclet number. Plug flow in the bonds of a physically representative network accounts for the only the first and third phenomena, resulting in a linear dependence of dispersion upon Peclet number. / text

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Environmental attitudes are shaped by a variety of factors including our educational history, cultural background, childhood and life experiences, and past and current interactions with nature. This research set out to examine attitudes toward the environment in an understudied but growing segment of the Canadian population, homeschoolers. The purposes of this study were to investigate whether environmental attitudes in Canadian homeschoolers differ from those of people involved with public school and to acquire a greater understanding of the factors that affect the development of these attitudes. The mixed method, follow-up explanatory research design utilized the New Ecological Paradigm Scale and the Connectedness to Nature Scale in an internet survey. The survey was sent to homeschooling and parent groups across Canada. Subsequently, interviews were conducted with a subsample of respondents. The results of the survey showed that demographic variables were not significantly related to environmental attitude scores with the exception of locale and religion. Urban respondents had slightly stronger environmental attitudes than rural respondents. The confluence of homeschooling and religiosity emerged as the key factor influencing environmental attitudes. There was no significant difference between environmental attitudes of homeschoolers and public schoolers until importance of religion was taken into account. As measured by the scales, religious homeschoolers exhibited the weakest environmental attitudes, public schoolers were in the middle, and not-as-religious homeschoolers had the strongest environmental attitudes. The qualitative data supported these results, with religious homeschoolers expressing weaker iv environmental attitudes, particularly in terms of climate change and the need for a more sustainable lifestyle. Religious homeschooling respondents favoured a more structured back to basics style of schooling which also correlated with lower environmental attitude scores. Unstructured homeschooling respondents tended to choose a child-centred philosophy of education which was correlated with stronger environmental attitudes. During the interviews, respondents were asked to reflect on what in their lives had influenced their attitudes toward the environment. Consistent with other literature, unstructured outdoor time as a child remained the most significant factor, cited by a majority of respondents. Other important factors included religion, parents, school, teachers, TV/media, economic necessity, and negative experiences with environmental pollution. The results of this study highlight the importance of considering variables associated with religion when exploring the development or level of environmental attitudes or when conducting a study of homeschooling. Religious beliefs are complex and highly personal in some cases, as is their corresponding influence on environmental concern. Potential exists for environmental concern and action from a group of spiritual people with strong community bonds and often political involvement. The key may be finding common ground and learning to communicate, while resisting expectations of complete agreement. This dissertation showed that stepping outside of the educational system does not necessarily have a direct impact on environmental attitudes, as they are mediated by a complex array of variables. Homeschooling may not directly generate a different level of environmental attitudes than public school; however, religious v homeschoolers definitely have a different set of attitudes toward the environment that deserve further in-depth study.

The intergenerational continuity of knowledge has become a concern as small-scale societies worldwide balance the challenges of adapting to environmental change associated with globalization while retaining continuity in their ways of life. This dissertation examines the intergenerational continuity of environmental knowledge through the conceptual lens of an Ethnoecology of Practice framework (EofP) developed to guide this research. Integrating insights from political ecology, social wellbeing and adaptive learning, the EofP provides theoretical and methodological tools based on practice theory to examine the knowledge of small-scale societies. Based on fieldwork in the community of Ponta Negra (Atlantic Forest Coast, Brazil), this dissertation uses a qualitative case study strategy of inquiry guided by a phenomenological worldview. Methods included participant observation, semi-structured interviews covering livelihoods, life histories and marine and terrestrial knowledge themes, document review and a census. Chapters 4 and 5 examine the perception of marine and terrestrial natural resources by tracing their social life from harvesting grounds to exchange and consumption sites. Chapters 6 and 9 analyse historical and contemporary adaptation to environmental change. While Chapter 6 describes the adoption of the pound net fishery, Chapter 9 illustrates contemporary modes of learning associated with natural resource harvesting and presents the processes associated with production of new knowledge through the example of local participation in the tourism economy. Chapter 7 examines local perspectives on livelihood transition from a social wellbeing perspective and highlights factors underlying the continuity of natural resource harvesting practice in Ponta Negra. Chapter 8 discusses how the term Caiçara, as used in biodiversity conservation and tourism development discourses, circumscribes the relation between coastal people and their local environments to a subsistence economy, denying their current economic engagements as well as their desires and aspirations. This dissertation contributes to ethnobiological understandings of the intergenerational continuity of knowledge by providing a framework and grounding evidence that demonstrates how knowledge is generated through context-specific practice attuned to dynamic environments that leads to individual innovation. It provides a theoretical contribution to our understanding of framing and creating processes inherent to human-in environment relations that lead to fluidity in ways of life over time.

Includes bibliography / vi, 153 [i.e. ca. 300] leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Entomology, 1985

Thesis (M.A. (Psychology))--Rhodes University, 2006. / Submitted in partial fulfilment of the Masters in Clinical Psychology.

Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2014. / Background: Practitioners are required to practice evidence-based medicine. The availability of large volumes of information make this practice style difficult for the practitioner. However, a systematic review allows literature to be organised, rated and allows current, abbreviated research resources for practitioner in clinical practice. Objectives: The effectiveness of the Gonstead Chiropractic Technique (GCT) was evaluated to present current evidence available for various conditions for which the GCT is utilised in clinical practice. Thus, the aim of the study was to systematically review, collate and evaluate the research evidence in the literature to determine the effectiveness of the GCT. Method: A literature search was conducted, based on key terms including: Gonstead and manual, Gonstead and technique, and Gonstead and manipulative/manipulation. Databases searched were: CINAHL Plus, Google Scholar, MEDLINE, Metalib, Pubmed, Science Direct, Springerlink and Summons. The articles were screened according to inclusion and exclusion criteria, after which secondary hand and reference searches were done. Thereafter the articles were reviewed by six independent reviewers. Appropriate scales were used to rate the methodological rigour of each article (e.g. PEDro). The results were analysed and ranked, before these outcomes were classified and contextualised in the clinical conditions on which the included studies were based. Results: A total of 477 citations were identified; after screening 26 English articles remained. Two articles were added through the secondary hand-search. Limited to no evidence existed for the effectiveness of GCT for neck pain / headache / face pain and limited evidence existed for gynaecological issues, scoliosis, neurological disorders, fractures, blood pressure and physiological presentations. Consensus was evident for gynaecological issues, neurological disorders, fractures (with the exception of the undiagnosed fracture) and physiological presentations, whereas the neck pain / headache / face pain and scoliosis were conflicting. Conclusion: Limited evidence shows a need for future studies with stringent methodological rigour, so as to investigate the appropriateness / inappropriateness of the use of the GCT. The lack of evidence for GCT may compromise appropriate informed consent and treatment. Therefore practitioners are encouraged to use appropriate and validated tools to measure the patient’s clinical progress

OBJECTIVES: The S100B protein subgroup is a thermolabile acidic calcium-binding protein. S100B protein was first described in the central nervous system. Destruction of the nerve tissue results in S100B protein release from astrocytic glial cells and elevation of its levels in the cerebrospinal fluid. If the blood-brain barrier is also damaged, S100B gets into the systemic circulation and elevated blood levels of S100B are detected. Higher S100B serum levels in patients with head injury are predictive of possible development of secondary brain injury and the extent of permanent injury to the CNS. MATHERIAL AND METHODS: The authors present their results obtained in the group of 39 children aged 0 (newborns) to 17 years with isolated craniocerebral injury. RESULTS: Our group included 39 children aged 0-17 years. Excellent results (GOS - Glasgow outcome scale 4-5) were observed in 33 patients already at the time of transfer from our ICU to the neurological department. There was no death and the poor outcome group included only 6 children. Second GOS evaluation was performed 6 months later, when 36 children were in the GOS 4-5 group and only 3 children in the GOS 2-3 group. CONCLUSIONS: Due to high variability in S100B protein serum levels in children depending on age and gender, no correlation between...

Growing demand on the limited resources available to head-injured individuals, emphasizes the need for accurate diagnosis and proper allocation of funds. Consequently, neuropsychologists are increasingly asked to render opinions regarding the validity of cognitive deficits reported following head injury. Detection of biased responding has typically been approached through the use of symptom validity measures and/or evaluation of performance patterns on standardized neuropsychological tests. This dissertation examined patterns of malingered performance on the Wechsler Adult Intelligence Scale-III (WAIS-III), Wechsler Memory Scale-III (WMS-III), and a self-report measure of physical and psychological symptoms. In addition, attempts were made to address several methodological concerns noted in previous analogue studies (e.g., allocation of preparation time). Malingered performance was compared to that of a normal control group (NC = 34) and a group of mildly head injured individuals (MHI = 22). Results revealed that the simulating group (SIM = 32) endorsed more subjective concerns than the NC group. On the cognitive measures, simulators showed a tendency towards general suppression of performance versus specific areas of deficit (e.g., attention). Specifically, the SIM group suppressed their performance on the WAIS-III, but not typically enough to differentiate them statistically from either the NC or MHI groups. The SIM group's performance on the WMS-III was more in keeping with the overall suppressed performance pattern reported in previous research. Although simulators often performed significantly worse than the NC group, they did not generally suppress their performance excessively when compared to the MHI group. Results obtained in this study may reflect the use of more detailed instructions or the preparation time allocated to the SIM group. Overall, these findings emphasize the importance of incorporating multiple detection measures to assure the accurate assessment and diagnosis of head injury. / Graduate

This study examined the effects of level and quality of education on WAIS-III Digit Symbol-Incidental Learning performance. The Pairing and Free Recall measures were administered to a South African sample (N = 68, age range 19-30), which was stratified for English and African language, level of education attained (Grade 12s and Graduates) and quality of education (advantaged and disadvantaged schooling). Results yielded no significant main or interaction effects between acculturation factors of level and quality of education. Normative guidelines of 13 or more pairs and 8 or more free recall symbols, appropriate to a non-clinical sample in a multicultural setting, are provided. Digit Symbol-Incidental Learning proved to be a culture-fair test, which contributes to its clinical utility as a sensitive memory screening tool.