Snap2Diverse: Coordinating Information Visualizations and Virtual Environments

The field of Information Visualization is concerned with improving with how users perceive, understand, and interact with visual representations of data sets. Immersive Virtual Environments (VEs) excel at providing researchers and designers a greater comprehension of the spatial features and relations of their data, models, and scenes. This project addresses the intersection of these two fields where information is visualized in a virtual environment. Specifically we are interested in visualizing abstract information in relation to spatial information in the context of a virtual environment. We describe a set of design issues for this type of integrated visualization and demonstrate a coordinated, multiple-views system supporting 2D and 3D visualization tasks such as overview, navigation, details-on-demand, and brushing-and-linking selection. Software architecture issues are discussed with details of our implementation applied to the domain of chemical information and visualization. Lastly, we subject our system to an informal usability evaluation and identify usability issues with interaction and navigation that may guide future work in these situations

Perforin-like protein PPLP2 permeabilizes the red blood cell membrane during egress of Plasmodium falciparum gametocytes

Egress of malaria parasites from the host cell requires the concerted rupture of its enveloping membranes. Hence, we investigated the role of the plasmodial perforin-like protein PPLP2 in the egress of Plasmodium falciparum from erythrocytes. PPLP2 is expressed in blood stage schizonts and mature gametocytes. The protein localizes in vesicular structures, which in activated gametocytes discharge PPLP2 in a calcium-dependent manner. PPLP2 comprises a MACPF domain and recombinant PPLP2 has haemolytic activities towards erythrocytes. PPLP2-deficient [PPLP2(−)] merozoites show normal egress dynamics during the erythrocytic replication cycle, but activated PPLP2(−) gametocytes were unable to leave erythrocytes and stayed trapped within these cells. While the parasitophorous vacuole membrane ruptured normally, the activated PPLP2(−) gametocytes were unable to permeabilize the erythrocyte membrane and to release the erythrocyte cytoplasm. In consequence, transmission of PPLP2(−) parasites to the Anopheles vector was reduced. Pore-forming equinatoxin II rescued both PPLP2(−) gametocyte exflagellation and parasite transmission. The pore sealant Tetronic 90R4, on the other hand, caused trapping of activated wild-type gametocytes within the enveloping erythrocytes, thus mimicking the PPLP2(−) loss-of-function phenotype. We propose that the haemolytic activity of PPLP2 is essential for gametocyte egress due to permeabilization of the erythrocyte membrane and depletion of the erythrocyte cytoplasm