Visualizing the 3D Architecture of Multiple Erythrocytes Infected with Plasmodium at Nanoscale by Focused Ion Beam-Scanning Electron Microscopy

Different methods for three-dimensional visualization of biological structures have been developed and extensively applied by different research groups. In the field of electron microscopy, a new technique that has emerged is the use of a focused ion beam and scanning electron microscopy for 3D reconstruction at nanoscale resolution. The higher extent of volume that can be reconstructed with this instrument represent one of the main benefits of this technique, which can provide statistically relevant 3D morphometrical data. As the life cycle of Plasmodium species is a process that involves several structurally complex developmental stages that are responsible for a series of modifications in the erythrocyte surface and cytoplasm, a high number of features within the parasites and the host cells has to be sampled for the correct interpretation of their 3D organization. Here, we used FIB-SEM to visualize the 3D architecture of multiple erythrocytes infected with Plasmodium chabaudi and analyzed their morphometrical parameters in a 3D space. We analyzed and quantified alterations on the host cells, such as the variety of shapes and sizes of their membrane profiles and parasite internal structures such as a polymorphic organization of hemoglobin-filled tubules. The results show the complex 3D organization of Plasmodium and infected erythrocyte, and demonstrate the contribution of FIB-SEM for the obtainment of statistical data for an accurate interpretation of complex biological structures

A framework for realistic real-time walkthroughs in a VR distributed environment

Virtual and augmented reality (VR/AR) are increasingly being used in various business scenarios and are important driving forces in technology development. However the usage of these technologies in the home environment is restricted due to several factors including lack of low-cost (from the client point of view) highperformance solutions. In this paper we present a general client/server rendering architecture based on Real-Time concepts, including support for a wide range of client platforms and applications. The idea of focusing on the real-time behaviour of all components involved in distributed IP-based VR scenarios is new and has not been addressed before, except for simple sub-solutions. This is considered as “the most significant problem with the IP environment” [1]. Thus, the most important contribution of this research will be the holistic approach, in which networking, end-systems and rendering aspects are integrated into a cost-effective infrastructure for building distributed real-time VR applications on IP-based networks

Situated interaction on spatial topics

In this thesis, we present a model and an implementation to handle situational interactions on spatial topics as well as several adaptation strategies to cope with common problems in real-world applications. The model is designed to incorporate situational factors in spatial reasoning processes at the basic level and to facilitate its use in a wide range of applications. The implementation realizing the model corresponds very closely to the structure of the model, and was put to test in a scenario of a mobile tourist guide. The adaptation strategies address the lack of information, resource restrictions as well as the problem of varying availability and quality of positional information.In dieser Arbeit stellen wir ein Modell zur Verarbeitung situierter Interaktionen über raumbezogene Sachverhalte und seine Implementation vor. Außerdem präsentieren wir verschiedene Strategien zum Umgang mit häufigen Problemen, die im Zusammenhang mit dem (mobilen) Einsatz von Systemen im realen Umfeld auftreten. Das zu Grunde liegende Modell bezieht situationsbezogene Faktoren auf unterster Ebene mit ein und erleichtert durch den modularen Aufbau seinen Einsatz im Rahmen verschiedener Anwendungen. Die entsprechende Implementation spiegelt die Struktur des Modells wider und wurde im Rahmen eines mobilen Touristenführers getestet. Die ebenfalls vorgestellten Adaptionsstrategien dienen unter anderem zur Behandlung von Informationsmangel und von Ressourcenbeschränkungen sowie zum Umgang mit dem Problem variierender Verfügbarkeit und Qualität von Positionsinformation