Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 339-359). Also available via the Internet

Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2004.

Background: Clinical studies have shown that tea consumption leads to decreased iron absorption. This finding is however, not supported by epidemiological studies, where no relationship between an increased tea consumption and a lower iron status in a population at risk of iron depletion has been found. Objectives: The main aim of this study was to compare the effects of black tea and Rooibos consumption on the iron status of primary school children in a rural setting in Potchefstroom, South Africa. Methods: One hundred and seventy five children, aged six to fifteen years, participated in this single blind, randomised, parallel intervention trial. Subjects were randomly allocated to receive two 200ml servings of either black tea or Rooibos with milk and sugar. These beverages were consumed during breaks and at the same time as the food h m the school-feeding scheme. The trial proceeded for sixteen weeks. The children received antihelminthic treatment (500mg mebendazole) at baseline. Haemoglobii haematocrit, serum iron, ferritin and transferfin were measured and total iron binding capacity and transferrin saturation were calculated. Trained fieldworkers measured dietary intakes by means of 24-hour dietary recalls and anthropometrists took anthropometric measurements. All the above mentioned data were gathered at the beginning and at the end of the intervention period. Results: Measurements indicated a study population that is malnourished in terms of anthropometrical indices and nutrient intakes. Biochemical markers of iron status also indicated that the population could be at risk of iron depletion. Changes in red blood cell count, haemoglobin, haematocrit, mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV), serum iron, transferrin, transferrin saturation, ferritin and total iron binding capacity (TIBC) did not differ significantly between the two groups. Mean red blood cell count, haematocrit, MCV, transferrin and TIBC increased significantly h m baseline to end in both groups (all p<0.0001) and MCH decreased significantly (p<.0001). Mean haemoglobin increased significantly with black tea consumption (p=0.002), although not with the consumption of Rooibos (p=0.073). Conclusion: Black tea or Rooibos consumption has similar effects on the iron status of primary school children. Iron status was not compromised by black tea in comparison with Rooibos. This questions the proposed limitation of black tea consumption as a public health strategy in order to combat iron deficiency in a population with marginal iron status. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2004.

Background: Clinical studies have shown that tea consumption leads to decreased iron absorption. This finding is however, not supported by epidemiological studies, where no relationship between an increased tea consumption and a lower iron status in a population at risk of iron depletion has been found. Objectives: The main aim of this study was to compare the effects of black tea and Rooibos consumption on the iron status of primary school children in a rural setting in Potchefstroom, South Africa. Methods: One hundred and seventy five children, aged six to fifteen years, participated in this single blind, randomised, parallel intervention trial. Subjects were randomly allocated to receive two 200ml servings of either black tea or Rooibos with milk and sugar. These beverages were consumed during breaks and at the same time as the food h m the school-feeding scheme. The trial proceeded for sixteen weeks. The children received antihelminthic treatment (500mg mebendazole) at baseline. Haemoglobii haematocrit, serum iron, ferritin and transferfin were measured and total iron binding capacity and transferrin saturation were calculated. Trained fieldworkers measured dietary intakes by means of 24-hour dietary recalls and anthropometrists took anthropometric measurements. All the above mentioned data were gathered at the beginning and at the end of the intervention period. Results: Measurements indicated a study population that is malnourished in terms of anthropometrical indices and nutrient intakes. Biochemical markers of iron status also indicated that the population could be at risk of iron depletion. Changes in red blood cell count, haemoglobin, haematocrit, mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV), serum iron, transferrin, transferrin saturation, ferritin and total iron binding capacity (TIBC) did not differ significantly between the two groups. Mean red blood cell count, haematocrit, MCV, transferrin and TIBC increased significantly h m baseline to end in both groups (all p<0.0001) and MCH decreased significantly (p<.0001). Mean haemoglobin increased significantly with black tea consumption (p=0.002), although not with the consumption of Rooibos (p=0.073). Conclusion: Black tea or Rooibos consumption has similar effects on the iron status of primary school children. Iron status was not compromised by black tea in comparison with Rooibos. This questions the proposed limitation of black tea consumption as a public health strategy in order to combat iron deficiency in a population with marginal iron status. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2004.

Haemoglobin concentration is becoming a widely popular parameter to use to assess physiological condition within a broad range of species. Assessments of large populations would preferable be done in field to receive quick results and avoid confounding factors associated with transport of blood. A validation study is here performed to see how well the point-of-care device HemoCue Hb 201 + can assess haemoglobin concentration on avian blood. Nucleated erythrocytes have previously been pointed out as something that makes it problematic to apply HemoCue Hb 201 +, designed for human blood, on avian blood. Here it is shown that HemoCue Hb 201 + accurately can estimate haemoglobin concentration for chicken-, tinamou-, and ostrich blood. However, manipulation of ostrich cells, to yield a larger mean corspuscular volume, results in HemoCue Hb 201 + overestimating haemoglobin concentration. A large mean corpuscular volume could therefore be something that impair accuracy in values retrieved with HemoCue Hb 201 +. This study shows that HemoCue Hb 201 + seems possible to apply on avian blood to some extent, but highlights the importance of validation studies when applying this device on new species.

Background: Iron deficiency, anemia, and iron excess have been associated with altered hearing functions in children and adults. Animal studies suggest that iron deficiency during pregnancy negatively affect fetal auditory development. The relationship between maternal iron status and auditory functions in healthy term newborns has not been clearly elucidated among humans. The goal of this pilot study was to determine the relationship between markers of iron status during pregnancy and brainstem auditory function in healthy neonates. Methods: Pregnant women who gave birth at the Montfort Hospital were recruited to take part in this study (n=6). Within two weeks after birth, their newborn’s hearing function was assessed by wave amplitude, latency and inter-latency from the Auditory Brainstem Response (ABR) test. Markers of iron status, namely hemoglobin (Hb) and mean corpuscular volume (MCV), were collected retrospectively for the first and second trimester from the women’s medical chart. Results: Overall, no significant relationship was observed between maternal Hb and MCV concentrations and newborns auditory function. Although two significant Spearman correlations were observed (MCV and inter-latency I-V; r=0.87; p=0.005 and Hb and amplitude V; r=0.89; p=0.04), these findings may be due to chance because of multiple testing and the small sample size. Conclusion: Although iron is a key nutrient involved in the brain and auditory system development, we were not able to demonstrate a relationship between iron status during pregnancy and newborn hearing function. Prospective or intervention studies with a larger sample size and with more specific iron markers (ex. ferritin) are required to confirm these findings.

Airbags are a passive safety technology, required to function with zero failure rate. Advances in Computer Aided Engineering have allowed vehicle manufacturers to predict material and system behavior in the event of a crash. The sudden and rapid nature of a vehicle frontal crash, together with strict requirements put on safety make this a sensitive task. This thesis focuses on the front passenger airbag deployment and the instrument panel’s response. Various airbag modelling techniques are studied and presented in this document. This work is part of a larger-scale attempt to model a generic-sled that is physically representative of a real vehicle. Various component tests are to be performed in the sled environment, as opposed to a real vehicle, to save costs. Various modules are added to the sled once their behavior is verified by testing and in simulations. Software are advanced enough to identify location and magnitude of stress concentrations that develop during crash. LS-DYNA is used for explicit finite element simulations of the instrument panel (IP) in question with different airbag models. Verification has been achieved by design of experiment (DOE); with tests conducted to capture both the movements of the airbag housing and IP movements in response. These movements are broken down in various phases, facilitating implementation in the sled environment. Simplifications are made both to the computer models as well as the physical testing environment. The effects of these simplifications are quantified and discussed. Theoretical background is provided where fit while assumptions are justified wherever made. DYNAmore recommendations regarding costeffective calculations as well as result verification are followed. The obtained results show that the FE models replicate the real event with acceptable precision. The findings in this work can, by minor tweaks, be implemented on other IP models in the Volvo Cars range, leading to cost-saving solutions. This thesis provides the necessary information for sled implementations as well as future improvement suggestions. / Krockkudde är en s.k. passiv säkerhetsteknik som krävs att fungera felfritt. Framsteg inom Computer Aided Engineering har tillåtit biltillverkare att förutsäga material och systembeteende i samband med krock. Den plötsliga karaktären av krock, tillsammans med höga säkerhetskrav, gör detta till en känslig uppgift. Denna avhandling fokuserar på passagerarsidans krockkudde och instrumentbrädans (IP) respons under uppblåsning. Olika metoder för modellering av krockkuddar har studerats och presenteras i detta dokument. Arbetet är en del av en större skala försök att modellera en generisk-släde som är fysiskt representativ av en riktig bil; där olika komponent-tester skall utföras för att minska kostnader. När olika modulers beteende verifieras läggs de till släden. Denna verifiering sker genom finita element (FE) simuleringar så väl som fysiska tester. FE mjukvara är idag tillräckligt avancerad för att identifiera samt visualisera spänningskoncentrationer som uppstår i en konstruktion vid krock. LS-DYNA används i detta arbete för explicita FE simuleringar av en Volvo XC90 IP, lastad med olika krockkudde-modeller. Modell verifiering har uppnåtts genom försöksplanering (DOE); med tester utförda för att fånga rörelser av IP så väl som krockkudde-behållaren. Dessa rörelser är sedan uppdelade i olika faser för enklare genomförande i släde miljön. Förenklingar och antaganden görs både till FE modeller och fysiska testmiljön. Effekter av dessa har kvantifierats och relevant teoretisk bakgrund har inkluderats. Dokumentet innehåller även diskussion kring val av mätutrustning samt förbättringsförslag för fortsatt arbete. DYNAmore rekommendationer gällande kostnadseffektiva beräkningar och verifiering av simulerings-resultat har följts. Under arbetet visade sig att FE modellerna kan återskapa händelsen med hög noggrannhet; dessa trotts svårigheter i modellering av plast material. Möjligtvis kan man, genom mindre modifieringar, relatera slutsatserna i detta arbete till olika IP modeller i företagets produktkatalog vilket förmodligen leder till ytterligare kostnadsbesparingar. Denna avhandling ger den information som behövs för genomföranden i den generiska miljön.

Sickle cell disease is a disabling chronic autosomal recessive blood disease characterized by abnormal hemoglobin, pain crises, and frequent emergency department visits. Adherence to hydroxyurea therapy has been shown to improve these patient outcomes. Guided by the theory of comfort, the purpose of this project was to determine if an educational intervention would increase adherence to hydroxyurea therapy in pediatric patients between 2 and 17 years of age recruited from an urban university hospital hematology clinic. The RE-AIM model was used to support the translation of evidence and the change process. An educational video produced by AFLAC was viewed by patients' parents 4 weeks after enrollment into this pretest/posttest design project. A total of 22 African-American parent participants completed the 8-item Morisky Medication Adherence Scale at baseline and again at 8 weeks to assess hydroxyurea adherence. The Short Test of Functional Health Literacy in Adults tool was used to assess parents' health learning needs; all parents met the adequate literacy level at baseline. Using t test statistics, no statistically significant differences were found pretest to posttest on the Morisky Medication Adherence Scale scores, mean corpuscular hemoglobin, and fetal hemoglobin percentages. Wilcoxon Signed Rank tests showed no significant differences in emergency room visits nor number of pain crisis. Although no significant changes emerged in short-term hematologic findings, emergency room visits, and pain crises, social change in the health care setting was promoted by confirming parents were able to understand education and a high level of hydroxyurea adherence was maintained; literature indicated that long-term adherence to hydroxyurea limits severe attacks.

This dissertation is an interdisciplinary study of scientific change. The undulatory theory of light replaces the emission theory of light in the early nineteenth century, triggering an "optical revolution" and vigorous debates among physicists in British from the 1830s to the 1850s. In this study I give the first full account of this extended episode of scientific change, drawing on methods and concepts from history, sociology and philosophy of science. The interdisciplinary account of the episode provides a basis for criticizing the existing models of scientific change in the philosophy of science. Previous historical studies of the “optical revolution" pay little attention to the period after the 1830s. Because the cognitive superiority of the undulatory theory had become obvious in the early 1830s, some historians have implicitly assumed that any controversy would soon come to a natural end. I, however, document that intensive debates continued from the 1830s until the end of the 1850s, and that emissionists even enjoyed temporary victories in their fights with undulationists. The narrative reveals the historical complexities of this episode: the debates extended long after the cognitive superiority of the undulatory theory should have become apparent by modern standard, the results of the debates did not necessarily coincide with modern cognitive judgements, and individual agents played decisive roles in determining how long a debate lasted and how it would end. On the basis of the historical narrative, I provide a philosophical analysis of the practices of theory appraisal and experiment appraisal that constituted the main theme of the controversy. Instead of merely identifying the criteria of evaluation employed in this episode, I pay special attention to how individual agents actually applied these criteria in concrete situations, what kinds of strategies or tactics they employed for the applications of these criteria, and how they created favorable conditions, both cognitive and social, for successfully applying these criteria. Individual agents’ efforts in selecting application strategies and in creating favorable conditions made the practices of appraisal complicated, exhibiting various features that are incomprehensible if we limit ourselves merely to studying the criteria of evaluation. I finally discuss a different approach to scientific change. The existing philosophical models of scientific change merely analyze the final product of science -- scientific theories, and ignore the impact of social factors and the role of individual agents. I suggest we concentrate on the process of knowledge production, and pay attention to individual agents’s practices in this process, as well as to the relevant cognitive and social factors that influence individual agents. Following this new approach, scientific change is understood as an evolution that involves interactions among three elements: theory, experiment, and human agent. / Ph. D.

This diploma thesis on the application of logical, empirical and statistical methods defined the role of the complementarity principle in the preparation of experts in the field of the protection of population in the framework of a quantitative research. The complementarity principle is characterized in the thesis in general (working with two expressions, both of them are necessary to explain the nature of the problem but cannot be used simultaneously, e.g. expressions "analysis" and "synthesis"). The diploma thesis then defined the physical aspect of the complementarity principle the wave-corpuscular dualism, the position and the momentum, the energy and the time. The comparison of the basics of the protection of population with the structure of the physical aspect of the complementarity principle followed. The performed comparison was adjusted to the needs and possibilities of future experts in the field of the protection of population on the basis of the theory of the curriculum process. The steps are clear from the set of objectives which were fulfilled gradually in the thesis: 1) To systematically describe the general form of the complementarity principle and its physical application from the point of view of the theory of the curriculum process. 2) To create a structure of the system of emergencies from the point of view of a scientific field of the protection of population and to focus on its educational aspect for the preparation of experts. 3) To perform the comparison of the physical aspect and emergencies with the general form of the complementarity principle. To transfer the findings, a theory of curriculum process was used. The link between a more generally approached complementarity principle and the protection of population was explained in the framework of a conceptual curriculum. The theory connecting these two different fields is the more generally approached complementarity principle and especially Bohr's complementarity principle linking not only the wave-corpuscular dualism but also Heisenberg's uncertainty principle. The physical aspect of emergencies was adjusted to the possibilities and needs of students (the intended curriculum) and written down in an educational text which was provided to students (the project curriculum). The practicality of the educational test was verified by an educational test the results of which were statistically processed (implemented curriculum). The statistical analysis of the test results confirmed the second hypothesis of this work. "The knowledge of future experts in the field of the protection of population will have, from the point of view of the role of the complementarity principle in their preparation, a theoretical division which will be close to the normal division." By confirming this hypothesis, the correctness and applicability of the curriculum process were confirmed as it was assumed by the first hypothesis: "Using the stages of a curriculum process, an educational basis of the role of the complementarity principle can be created within a quantitative research." The contributions of this work can be summarized by following points: 1) The use of an educational text in the preparation of experts in the field of the protection of population (a practical contribution of this diploma thesis). 2) The improvement of the applicability of the theory of the curriculum process in the field of the protection of population which has not been researched so far (the improvement of the theory of the curriculum process). 3) The definition of the link of the physical aspect of the complementarity principle to the general form of this principle (the theoretical contribution of this diploma thesis).