· · · Repository hosted by TU Delft Library

In this paper we describe the context-aware Adaptive Daily Rhythm Atmosphere (ADRA) system. The ADRA system is designed to stimulate thehealing of hospital patients, neurology patients in particular. Wefirst report on the needs and issues of neurology patients based ona observation study in a hospital neurology ward. Based on these needs, we define several of concepts to promote healing. Finally, the context-aware system to realize these concepts is described, as wellas how the system is implemented in practice.

Using the inverse-electron-demand Diels Alder reaction we demonstrated non-invasive pretargeted tumor imaging in mice bearing LS174T colorectal xenografts. Anti-TAG72 mAb CC49 functionalized with trans-cyclooctene moieties was administered, followed 24 h later by 111In-labeled tetrazine. Pronounced tumor uptake of the 111In-tetrazine was demonstrated by SPECT/CT imaging of live mice up to 3 h post injection (tumor-to-muscle ratio: 13.1), while no tumor binding occurred in mice treated with unmodified CC49. The components exhibited a remarkable 52-57 % chemical reaction yield in mice. We are currently optimizing this system for cancer therapy.

We investigate the potential to enhance breast cancer event predictors by exploiting subtype information. We do this with a two-stage approach that first determines a sample's subtype using a recent module-driven approach, and secondly constructs a subtype-specific predictor to predict a metastasis event within five years. Our methodology is validated on a large compendium of microarray breast cancer datasets,including 43 replicate array pairs for assessing subtyping stability. Note that stratifying by subtype strongly reduces the training set sizes available to construct the individual predictors, which may decrease performance. Besides sample size, other factors likeunequal class distributions and differences in the number of samplesper subtype, easily obscure a fair comparison between subtype-specific predictors constructed on different subtypes, but also between subtype specific and subtype a-specific predictors. Therefore, we constructed a completely balanced experimental design, in which none ofthe above factors play a role and show that subtype-specific eventpredictors clearly outperform predictors that do not take subtype information into account.

In order to guide our actions, the human brain relies most on the information that is received from the visual sense. However, the visual input the brain receives through the eyes is often subject to noise and ambiguity. Consider for example a person driving a car throughthe fog. In this situation, the visual information that the brain receives is severely degraded. It is obvious that the brain needs a way to resolve such ambiguities in order to be able to provide the reliable visual information necessary to guide our actions. The neuralmechanisms that are involved in resolving ambiguity in the visual input have been the subject of many studies for over a century. In recent years, many studies have used psychophysics and neuroimaging toinvestigate how and where the brain processes and resolves ambiguous visual information. In this study we used a structure-from-motionstimulus to investigate the neural responses during the viewing of an ambiguous stimulus. To investigate these neural responses underlying ambiguous visual perception we used a novel approach. Intracranial electroencephalography is a relatively new method that provides several advantages over more commonly used methods such as scalp EEGor magnetic resonance imaging. The electrodes that are used to record the electrical activity of the brain are implanted directly on thesurface of the brain. This allows for more accurate measurements ofbrain activity becausethere is no interference from the skull and skin which cause problems in scalp EEG.Using intracranial EEG, we identified two separate locations in the left hemisphere of one partici-pant that showed a significant difference in alpha band power during a switch in perception when viewing an unambiguous stimulus compared to viewing an ambiguous stimulus. This difference could indicatethat the neuronal populations at theselocations respond preferentially to bottom-up visual information and not to top-down visual information. A subsequent analysis of the time-frequency spectrum revealedno significant differences but clearly showed a decrease in power in the lower frequencies before the participant responded to a changein the stimulus. This decrease in power is likely related to the preparation of the motor response. The results of this study show thatintracranial EEG is useful new method that can provide an improvement over both scalp EEG and MRI.

The High Definition scene is constantly changing. The arrival of Full HD flat panel displays, the constant improvement of the AVC encoder, and the trend towards 1920x1080 progressive broadcasting have changed the balances of the High Definition broadcasting chain. It is, therefore, required to revisit the TV-formats debate. This research project was set up to consider: End-viewer perceived quality for critical content when broadcasting 720p/50, 1080i/50, and 1080p/50. End-viewer perceived quality for critical content encoded with MPEG 2, VC1 and H.264/AVC in various bitrates. Industry trend to migrate from MPEG 2 at 18 Mbps to AVC at 12 Mbps. New techniques for better usage of the available bitrate. Research during the project showed that: MPEG 2 and AVC have different types of artifacts but the overall perceived quality is similar for the same bitrate. The choice depends on the viewer. 1080i/50 quality is highly dependent on the set of(de-) interlacer. A possible solution for better bitrate usage could be frame sub-sampling prior the encoding and frame interpolation on the decoder. Tests showed that it can work only for content with smooth motion or temporally filtered. For a certain bitrate, there is an optimal tradeoff between the resolution format and the perceived quality. It is, though, highly content dependent and therefore not easily exploitable.The results of the perception test conducted showed that: 720p, 1080i, and 1080p have differences in quality, not statistically significant for MPEG 2 encodings. 1080p and 720p are preferred to1080i for AVC encodings. Viewers prefer MPEG 2 artifacts to AVC arti-facts. Viewers prefer MPEG 2 at 18 Mbps to AVC at 12 Mbps Subjects that need to be investigated: The role of Kell factor in the comparison between 1080p and 720p for-mats. The simulation of the broadcast chain with less critical content.