Hemos analizado el efecto de la IL-12 sobre la enfermedad autoinmune en un modelo murino semialogénico de enfermedad crónica de injerto contra el huésped (EICHc) inducida en ratones (Balb/c X A/J) F1 (CAF1) inyectados por vía intraperitoneal con células semialogénicas de la cepa parental BALB/c. La IL-12 fue administrada 1 h antes del transplante de células semialogénicas siguiendo dos protocolos diferentes de administración: (a) inyectando 2 g de rmIL-12 (IL-12 murina recombinante) por ratón antes de la primera inyección de células semialogénicas; o (b) inyectando los 2 g de rmIL-12 fraccionada en 5 días. Se produjo una respuesta Th1 pero no apareció la enfermedad aguda de la EICH a pesar de las diferencias en clase I y II de antígenos del complejo mayor de histocompatibilidad (MHC) entre donante y receptor. Cuatro días después de la transferencia de células semialogénicas, los ratones tratados con rmIL-12 mostraron una marcada reducción en el porcentaje de células B comparado con animales control CAF1 y ratones con EICH CAF1+BALB/c. Después de 5-6 meses de seguimiento de la enfermedad, el quimerismo de células donantes incrementó significativamente en bazo (70  31 vs 43  31 %) y en timo. La citometría de flujo de esplenocitos demostró que el quimerismo de células donante estaba constituido por linfocitos T CD4, T CD8 y B y los porcentajes fueron más elevados en animales inyectados con IL-12. Además, el 100% de linfocitos T CD8 fueron de origen donante en los animales con EICH tratados con IL-12 y el 50 % fueron de origen donante en los animales con EICH no tratados. Los resultados demostraron que: (1) La IL-12 probablemente juega un papel en el mecanismo del quimerismo de células donantes, probablemente producido por mecanismos mediados por CTL donantes anti-huésped; (2) no induce la enfermedad aguda de ICH a pesar de las diferencias en clase I y II de moléculas del MHC; (3) la IL-12 no muestra ningún efecto sobre signos clínicos de la enfermedad AR-like desarrollada en este modelo de EICH aunque los signos subclínicos histológicos fueron menos frecuentes, y no se detectó glomerulonefritis en ratones con EICH tratados con IL-12. / We analyzed the IL-12 effect in an autoimmune disease induced in a semiallogenic murine model of graft-vs-host disease (GVHD) Balb/c semiallogenic lymphoid cells i.v. infected in hybrid mice (Balb/c x A/J) F1 (CAF). IL-12 was administered 1 h before cell transplantation following two different protocols: (a) injecting 2 microg of mrIL-12 (murine recombinant IL-12) per mouse before the first semiallogenic cell injection; or (b) injecting the 2 microg of mrIL-12 fractionated in 5 days. ATh1 response was produced but an acute GVHD did not appear although differences in class I and II major histocompatibility complex (MHC) antigens were present. Four days after the semiallogenic cell transfer, IL-12 treated mice showed a marked reduction in the percent of spleen B cells compared with CAF1 control and CAF1 + Balb/c GVHD mice. After 5-6 months of follow-up, the donor cell chimerism increased significantly in spleen (70 +/- 31 vs. 43 +/- 31%) and in thymus. Flow cytometry of spleen lymphocytes demonstrated that donor chimerism was made up of TCD4, TCD8 and B lymphocytes and was higher in animals injected with IL-12. Moreover, CD8 T lymphocytes were 100% donor origin in the IL-12-injected group of GVHD animals and 50% origin in the IL-12-non-injected CAF1 + Balb/c group of animals. This paper shows that: (1) IL- 12 may play a role in the mechanisms of donor cell engraftment, probably produced by a CTL donor anti-host mechanism; (2) no acute GVHD was induced in spite of class I and II MHC differences; (3) IL-12 did not show any effect on the AR-like clinical signs of disease developed in this model of GVHD although histological subclinical signs were less frequent, and no glomerulonephritis was detected in the IL-12-treated GVHD mice.

Thin-film theorems are well developed and so are the fabrication processes. Yet under some special conditions, traditional methods (such as the ABCD matrix and the transmission matrix methods) will lead to a serious numerical error. In this thesis, we propose a new method called Couple E/H field formulation, which will overcome this numerical problem in simulating characteristics of complex multi-layered structures. We have verified both the algorithm and its results with the traditional techniques. By extending the impedance matching principle, we came out with a multi-layer anti-reflection coating design optimized for a time-harmonic plane wave incidence with any incident angle. Such a design allows for more plane waves with adjacent angles to pass through the coating layers with minimal reflection. Furthermore, we apply this AR coating design to facets of semiconductor lasers. Our calculation shows that multi-layer coating does a better job than a single layer coating. The reflectivity of a laser diode from single layer coating 0.085% to 5 layer coating 0.056%, which is a 33% improvement.

This study investigates augmented reality using third person perspective and what precision can be achieved by using this method. There have been prior studies in regards to precision using augmented reality, however studies using third person perspective is scarce. This study presents a solution using a static camera capturing the user as well as the plane to augment from behind. This augmented image is then transferred to a handheld device that is held by the user. Using this method the user will be free to manipulate and work with the plane without removing the device that captures the scene, a common problem when using visual reference markers in augmented reality. The study successfully shows that this can be implemented without compromising user experience as well as achieving a precision below 13 millimeters. The AR-tool has been proven to reduce time consumption of the task by up to four times compared to the manual method using a folding ruler.

Augmented Reality (AR) is a powerful tool for the visualisation of, and interaction with, digital information, and has been successfully deployed in a number of consumer applications. Despite this, AR has had limited success in industrial applications as the combined precision, accuracy, scalability and robustness of the systems are not up to industry standards. With these characteristics in mind, we present a concept Industrial AR (IAR) framework for use in outdoor environments. Within this concept IAR framework, we focus on the improving the precision and accuracy of consumer level devices by focusing on the issue of localisation, utilising LiDAR based point clouds generated as part of normal surveying and engineering workflow. We evaluate key design points to optimise the localisation solution, including the impact of increased field of view on feature matching performance, the filtering of feature matches between real imagery and an observed point cloud, and how pose can be estimated from 2D to 3D point correspondences. The overall accuracy of this localisation algorithm with respect to ground-truth observations is determined, with unfiltered results indicating an on par horizontal accuracy and significantly improved vertical accuracy with best-case consumer GNSS solutions. When additional filtering is applied, results of localisation show a higher accuracy than best-case consumer GNSS.

Produsente van landboukommoditeite, veral in ontwikkelende lande, word blootgestel aan prysrisiko's. Markte vir landboukommoditeite in Suid-Afrika, soos in die res van die wêreld, is die afgelope aantal jare gekenmerk deur prosesse van deregulering. Die bemarkingsrade wat aanvanklik verantwoordelik was vir die bemarking van landbouprodukte, het ontbind en produsente van landbouprodukte moes nuwe metodes vind om hulle produkte te bemark. Een van die metodes wat gebruik word, is termynkontrakte. Witmielies en geelmielies is die twee landboukommoditeite wat in die grootste hoeveelhede geproduseer word in Suid-Afrika. Witmielies en geelmielies word as twee afsonderlike kommoditeite verhandel op die termynbeurs. Witmielies word hoofsaaklik aangewend vir menslike verbruik en geelmielies vir dierevoer. Hierdie studie fokus hoofsaaklik op witmielies. Die prys van mielies word beïnvloed deur veranderinge in die vraag daarna en aanbod daarvan. Faktore wat die vraag en aanbod van mielies beïnvloed is, onder andere, oesskattings, reënval, die wisselkoers en die pryse van mielies op die buitelandse mark, veral die markte in die VSA. In Suid-Afrika vorm die invoerpariteit en uitvoerpariteit 'n band waarbinne die prys van mielies varieer. Die doel van hierdie studie is om 'n regressievergelyking te konstrueer ten einde prys van die witmielietermynkontrakte te verklaar. Die regressie-analise word deur middel van 'n foutherstellende model met outoregressiewe foutterme behartig. Die regressie-analise slaag daarin om die prys van witmielietermynkontrakte te verklaar. / Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2004.

The goal of this research thesis is to explore and evaluate a novel interaction interface performing canonical manipulations in 3D space for Augmented Reality (AR) on handheld devices. Different from current handheld AR applications usually using touch-screen based interaction methods, we developed a 3D gesture based interaction approach for handheld AR using an attached RGB-Depth camera to provide intuitive 3D interaction experience in 3D space. By identifying fingertips and mapping their 3D positions into the coordinate system of AR virtual scene, our proposed method allows users to perform operations on virtual objects using their fingers in midair with six-degrees-of-freedom (6DOF). We applied our methods in two systems: (1) a client-server handheld AR system, and (2) a standalone handheld tablet AR system. In order to evaluate the usability of our gesture-based interface we conducted a user study in which we compared the performance to a 2D touch-based interface. From the results, we concluded that traditional 2D touch-based interface performed faster than our proposed 3D gesture-based interface. However, our method proved a high entertainment value, suggesting great possibilities for leisure applications.

Produsente van landboukommoditeite, veral in ontwikkelende lande, word blootgestel aan prysrisiko's. Markte vir landboukommoditeite in Suid-Afrika, soos in die res van die wêreld, is die afgelope aantal jare gekenmerk deur prosesse van deregulering. Die bemarkingsrade wat aanvanklik verantwoordelik was vir die bemarking van landbouprodukte, het ontbind en produsente van landbouprodukte moes nuwe metodes vind om hulle produkte te bemark. Een van die metodes wat gebruik word, is termynkontrakte. Witmielies en geelmielies is die twee landboukommoditeite wat in die grootste hoeveelhede geproduseer word in Suid-Afrika. Witmielies en geelmielies word as twee afsonderlike kommoditeite verhandel op die termynbeurs. Witmielies word hoofsaaklik aangewend vir menslike verbruik en geelmielies vir dierevoer. Hierdie studie fokus hoofsaaklik op witmielies. Die prys van mielies word beïnvloed deur veranderinge in die vraag daarna en aanbod daarvan. Faktore wat die vraag en aanbod van mielies beïnvloed is, onder andere, oesskattings, reënval, die wisselkoers en die pryse van mielies op die buitelandse mark, veral die markte in die VSA. In Suid-Afrika vorm die invoerpariteit en uitvoerpariteit 'n band waarbinne die prys van mielies varieer. Die doel van hierdie studie is om 'n regressievergelyking te konstrueer ten einde prys van die witmielietermynkontrakte te verklaar. Die regressie-analise word deur middel van 'n foutherstellende model met outoregressiewe foutterme behartig. Die regressie-analise slaag daarin om die prys van witmielietermynkontrakte te verklaar. / Thesis (M.Com. (Economics))--North-West University, Potchefstroom Campus, 2004.

Tübingen, Universiẗat, Magisterarbeit, 2006.

Thesis (D. Min.)--Midwestern Baptist Theological Seminary, 2001. / Abstract. Includes bibliographical references (leaves 215-218).

Thesis (D. Min.)--Midwestern Baptist Theological Seminary, 2001. / Abstract. Includes bibliographical references (leaves 134-135).