Elevated intraocular pressure (IOP) is one of the major risk factors for glaucoma. Since glaucoma is a leading cause of blindness, reliable methods for measuring the IOP are important. This doctoral dissertation presents a new method, applanation resonance tonometry (ART), for measurement of IOP. The method is based on resonance sensor technology combined with the novel multipoint analysis of continuously sampled data of both contact force and contact area. The ART was evaluated in in vitro porcine-eye studies as well as in clinic on both healthy volunteers and patients. A new symmetric probe with a larger sensor tip and improved aligning light was developed and evaluated in vitro. It showed that the error from off-centring was highly reduced. The new ART probe, used as a biomicroscope device (ARTBiom) and as a handheld device (ARTHand), was further evaluated in a clinical study designed in accordance with the International Standard Organisation’s (ISO) requirement. Both the ARTBiom and the ARTHand met the precision set by the requirements. Laser surgery is a common way to correct vision. The biomechanical effect of photorefractive keratectomy (PRK) on IOP measurements was evaluated using Goldmann applanation tonometry (GAT) and ART in an in vitro study. Both methods were affected, but to a different extent. The flat contact probe of GAT, as compared with the convex tip of ART, and single point vs. multipoint approach, provide explanation to the ART advantage regarding measurement error of IOP after PRK. In conclusion, resonance sensor technology has made it possible to introduce a new multipoint method for measuring IOP, and the method is relevant for measuring IOP in humans. It may be possible to reduce errors in the clinical measurement of IOP with this new method, especially after corneal surgery. The ART has the potential to become a useful clinical instrument for IOP measurement.

Dans la critique littéraire française des années 1950-1960, certains éléments apparaissent comme des évidences. Malgré les différences des méthodes, une idée sous-tendait toutes les lectures : il y aurait, dans les textes, des significations cachées qu’une interprétation devrait révéler. Dans les travaux des trois auteurs étudiés (Charles Mauron, Lucien Goldmann et Roland Barthes), on peut repérer des images qui traversent leurs œuvres et qui sont liées à leurs conceptions de l’objet littéraire. Or, ce qui est intéressant dans leur critique, c’est qu’il est impossible de trouver des éléments qui décrivent les textes qui ne soient imaginaires : en suivant le fil des interprétations de ces auteurs, il n’y a pas de moment où l’image cesse d’agir, comme si le propre du texte se dérobait à chaque fois sous le travestissement d’une autre image.Ces images montrent que la critique littéraire de l’époque étudiée accomplissait deux gestes, proches de deux figures de langage. La tautologie est ce qui ne réussit à établir un rapport de l’objet qu’avec lui-même. Le paradoxe fait le mouvement contraire, puisqu’il repose sur l’idée que les différences doivent être authentiques.Or, ce que l’imaginaire des auteurs donne à voir, c’est une certaine notion de la littérature. Leurs images témoignent de la construction de la littérature comme une pratique discursive marginale : ce qui intéresse les auteurs, c’est de voir ces textes comme un acte de résistance, capable d’utiliser un langage qui défie les usages « normaux » de la langue. Mais, paradoxalement, ils tendent à naturaliser cette position marginale et légitimer la place centrale occupée par les sciences et par la philosophie. / In French literary critique of the years 1950-1960, certain elements were seen as evidences. Despite the differences between the methods the authors used, one idea was always present: for them, the texts concealed hidden meanings that their analyses were meant to reveal. In the works of the three authors we chose to study (Charles Mauron, Lucien Goldmann and Roland Barthes), it is possible to find images that are related to a certain conception of literature. It is interesting to note that in their methods, it is impossible to find definitions of the text that are not touched by an imaginary activity. Reading the authors, we realise that images are everywhere, as if the text itself constantly eluded the analysis.The images show that the literary critique of the time performed two different gestures, that correspond to two figures of speech. Tautology is the figure that establishes that an object can only be defined by itself. Paradox does the exact opposite, stating that only in difference can we find its identity.By analysing the authors’ imaginary, one can reconstruct a certain idea of literature. Their images show literature as a marginal discourse: their interest in literary texts lies in the fact that they can resist the “normal” usage of language. But, paradoxically, this way of looking at them tends to naturalise their marginal position and thus legitimate the privilege accorded to science and philosophy as the standard form of expression.

La presente tesi tratta del fenomeno dello sviluppo della visione del mondo, da un punto di vista sociologico, seguendo la teoria e il metodo di critica letteraria del saggista marxista Lucien Goldmann, che si focalizza sul ruolo di contesti socioeconomici e temporali. Il materiale primario di analisi è costituito dei due romanzi Lessico famigliare di Natalia Ginzburg e Les armoires vides (“Gli armadi vuoti”) di Annie Ernaux.

Purpose: The aim of the study was to quantify the isolated tear film adhesion error in a Goldmann applanation tonometer (GAT) prism and in a correcting applanation tonometry surface (CATS) prism. Methods: The separation force of a tonometer prism adhered by a tear film to a simulated cornea was measured to quantify an isolated tear film adhesion force. Acrylic hemispheres (7.8 mm radius) used as corneas were lathed over the apical 3.06 mm diameter to simulate full applanation contact with the prism surface for both GAT and CATS prisms. Tear film separation measurements were completed with both an artificial tear and fluorescein solutions as a fluid bridge. The applanation mire thicknesses were measured and correlated with the tear film separation measurements. Human cadaver eyes were used to validate simulated cornea tear film separation measurement differences between the GAT and CATS prisms. Results: The CATS prism tear film adhesion error (2.74 +/- 0.21 mmHg) was significantly less than the GAT prism (4.57 +/- 0.18 mmHg, p<0.001). Tear film adhesion error was independent of applanation mire thickness (R-2=0.09, p=0.04). Fluorescein produces more tear film error than artificial tears (+0.51 +/- 0.04 mmHg; p<0.001). Cadaver eye validation indicated the CATS prism's tear film adhesion error (1.40 +/- 0.51 mmHg) was significantly less than that of the GAT prism (3.30 +/- 0.38 mmHg; p=0.002). Conclusion: Measured GAT tear film adhesion error is more than previously predicted. A CATS prism significantly reduced tear film adhesion error by similar to 41%. Fluorescein solution increases the tear film adhesion compared to artificial tears, while mire thickness has a negligible effect.

It is widely known that Central Corneal Thickness (CCT) and Radius of Curvature (RoC) in uence the estimated IntraOcular Pressure (IOP) obtained from Goldmann Applanation Tonometry (GAT). However, not much is known about the in uence of corneal material properties, especially in a clinical setting. Several numerical studies have been conducted in an attempt to quantify the in uence of corneal material properties on the IOP. These studies agree that corneal material properties do in uence the estimated IOP, which contradict the initial premise on which GAT was designed, namely that material properties do not in uence the obtained GAT readings. Also, there is no consensus among these studies with respect to corneal material properties, thus a wide range of proposed properties exist. A possible explanation for this range of available corneal properties is the numerical modi elling assumptions used, which seem to be quite different. Different sets of experimental in ation test data were used to calibrate the constitutive models and different limbal boundary conditions were applied to simulate the experimental setup as well as in vivo conditions during GAT simulations. Therefore the purpose of this study is to determine whether these modelling assumptions in uence the obtained IOP and ultimately the overall conclusions. A Finite Element (FE) model of the human cornea is developed, implementing a constitutive model to represent the complex corneal structure and two limbal boundary conditions. This model is then calibrated using two different sets of experimental in ation test data. During calibration of the fibre reinforced elastic constitutive model it is found that independent of the assumptions made regarding the material coe cients, that the numerical in ation data compare well with the experimental data for all cases. Using this model a GAT simulation is conducted to estimate the IOP and the in uence of the modelling assumptions, cornea geometry and material properties are then investigated. The results indicate that the modelling assumptions, cornea geometry and material properties do infuence the estimated IOP. However, when assuming the cornea ground substance stiffness to be constant, it is found that the in uence on IOP due to material properties is not as significant. A correction equation is also proposed to account for the corneal geometric properties by calibrating the numerical model for a numerically normal cornea. This is done by utilising the various data sets which are obtained during the calibration of the constitutive model with the experimental inflation test data. It is concluded that using only inflation data to calibrate the constitutive model is not sufficient to uniquely describe the corneal material. This is evident as different material data sets are obtained, even though the experimental inflation data is matched well for a variety of considered cases. Each of these material data sets, in conjunction with geometric properties, yield different estimates for IOP during GAT simulations. This study therefore recommends the use of additional experimental data, such as strip extensometry, along with inflation test data to adequately calibrate a numerical model. It should also be noted that when modelling GAT care should be taken when considering the choice of limbal boundary condition, experimental data for calibration and assumptions made with regards to material coe cients, as these choices could potentially influence the outcomes and conclusions of a study. / Dissertation (MEng)--University of Pretoria, 2014. / gm2014 / Mechanical and Aeronautical Engineering / unrestricted

Purpose: Clinically evaluate a modified applanating surface Goldmann tonometer prism designed to substantially negate errors due to patient variability in biomechanics. Methods: A modified Goldmann prism with a correcting applanation tonometry surface (CATS) was mathematically optimized to minimize the intraocular pressure (IOP) measurement error due to patient variability in corneal thickness, stiffness, curvature, and tear film adhesion force. A comparative clinical study of 109 eyes measured IOP with CATS and Goldmann prisms. The IOP measurement differences between the CATS and Goldmann prisms were correlated to corneal thickness, hysteresis, and curvature. Results: The CATS tonometer prism in correcting for Goldmann central corneal thickness (CCT) error demonstrated a reduction to <+/- 2 mmHg in 97% of a standard CCT population. This compares to only 54% with CCT error <+/- 2 mmHg using the Goldmann prism. Equal reductions of similar to 50% in errors due to corneal rigidity and curvature were also demonstrated. Conclusion: The results validate the CATS prism's improved accuracy and expected reduced sensitivity to Goldmann errors without IOP bias as predicted by mathematical modeling. The CATS replacement for the Goldmann prism does not change Goldmann measurement technique or interpretation.

Ce projet de recherche a pour but d’étudier le processus créatif, l’apprentissage social, la rationalité, les conflits, les règles et les normes de trois groupes d’auteurs contemporains à New York et à Paris. Les méthodes de recherche incluent des entretiens avec des auteurs, la narration d’anecdotes sur le comportement des acteurs sociaux, la construction d’un tableau sociométrique des règles et des normes propres à chaque groupe d’après la théorie de Howard BECKER, et une analyse de texte qui mobilise la méthode d’étude structurale du sociologue de la littérature Lucien GOLDMANN. Ce projet de recherche a permis l’identification des niches sociales d’auteurs contemporains, dans lesquelles des échanges d’informations permettent un apprentissage social qui a de la valeur professionnelle et personnelle pour les acteurs sociaux en question. Enfin, ce projet de recherche permettra le placement des auteurs contemporains dans l’organigramme de la production culturelle de Pierre BOURDIEU, qui distingue « le sous-champ de l’avant-garde », « le sous-champ de la grande production » et « le champ du pouvoir » dans le monde littéraire. / The purpose of this research project is to explore the creative process, social learning, motivation, conflicts, rules and norms of three groups of contemporary writers in New York and Paris. Research methods include interviews with authors, the narration of anecdotes about the behavior of the social actors, and the construction of a sociometric table of rules and norms specific to each group according to the theory of Howard BECKER. This project also offers contains a literary analysis using Lucien GOLDMANN’s method of structural study. This research led to the identification of social networks of contemporary authors, in which the exchange of information allows social learning that has both professional and personal value for the social actors in question. Finally, this research will allow the placement of contemporary authors into Pierre BOURDIEU’s map of cultural production, which distinguishes “the sub-field of the avant-garde,” “the sub-field of large-scale production,” and “the field of power” in the literary world.

Diss. : Freiburg im Breisgau : 1992. / Bibliogr. p. 277-297.

Background: Compare Goldmann applanation tonometer (GAT) prism and correcting applanation tonometry surface (CATS) prism to intracameral intraocular pressure (IOP), in vivo and in vitro. Methods: Pressure transducer intracameral IOP was measured on fifty-eight (58) eyes undergoing cataract surgery and the IOP was modulated manometrically to 10, 20, and 40 mmHg. Simultaneously, IOP was measured using a Perkins tonometer with a standard GAT prism and a CATS prism at each of the intracameral pressures. Statistical comparison was made between true intracameral pressures and the two prism measurements. Differences between the two prism measurements were correlated to central corneal thickness (CCT) and corneal resistance factor (CRF). Human cadaver eyes were used to assess measurement repeatability. Results: The CATS tonometer prism measured closer to true intracameral IOP than the GAT prism by 1.7+/-2.7 mmHg across all pressures and corneal properties. The difference in CATS and GAT measurements was greater in thin CCT corneas (2.7+/-1.9 mmHg) and low resistance (CRF) corneas (2.8+/-2.1 mmHg). The difference in prisms was negligible at high CCT and CRF values. No difference was seen in measurement repeatability between the two prisms. Conclusion: A CATS prism in Goldmann tonometer armatures significantly improve the accuracy of IOP measurement compared to true intracameral pressure across a physiologic range of IOP values. The CATS prism is significantly more accurate compared to the GAT prism in thin and less rigid corneas. The in vivo intracameral study validates mathematical models and clinical findings in IOP measurement between the GAT and CATS prisms.

In 2005 the Swedish social democratic government settled a defense treaty with Saudi Arabia. Ten years later, a new Social democratic government ends the treaty. This thesis will study the Social democratic party’s motives behind their actions regarding the treaty. Kjell Goldmanns theory regarding the three fields of interest concerning state’s foreign policy, security policy, economy and international values, will serve as the theory and operationalization of this thesis. The thesis will operate an analysis of motives to study the main motives of the party’s actions during four events. After examining the actions of the Social democrats in media and the parliament, the thesis found that the party had changed their main motives between 2005 and 2015. Their main motives in 2005 were economical and in 2015 were their main motives international values, which reaches the conclusion that the Social democrats have changed their motives regarding the treaty.