Wicked Neuroarchitecture: Reciprocity, Shapeshifting Problems and a Case for Embodied Knowledge

Wicked problems are difficult or impossible to solve because of incomplete, changing or even contradictory conditions. Both architecture and neuroscience work on wicked problems as a matter of course. The utilisation of evidence-based design by some neuroarchitecture researchers implies that architecture is subservient to neuroscience, simply a matter of designing brain impulses. Fiona Zisch, lecturer in architecture and a neuroarchitecture researcher based in London and Innsbruck, suggests otherwise

The Impact of a Self-Avatar on Cognitive Load in Immersive Virtual Reality

The use of a self-avatar inside an immersive virtual reality system has been shown to have important effects on presence, interaction and perception of space. Based on studies from linguistics and cognition, in this paper we demonstrate that a self-avatar may aid the participant’s cognitive processes while immersed in a virtual reality system. In our study participants were asked to memorise pairs of letters, perform a spatial rotation exercise and then recall the pairs of letters. In a between-subject factor they either had an avatar or not, and in a within-subject factor they were instructed to keep their hands still or not. We found that participants who both had an avatar and were allowed to move their hands had significantly higher letter pair recall. There was no significant difference between the other three conditions. Further analysis showed that participants who were allowed to move their hands, but could not see the self-avatar, usually didn’t move their hands or stopped moving their hands after a short while. We argue that an active self-avatar may alleviate the mental load of doing the spatial rotation exercise and thus improve letter recall. The results are further evidence of the importance of an appropriate self-avatar representation in immersive virtual reality

Current concepts in periodontal bioengineering

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73112/1/j.1601-6343.2005.00352.x.pd

Quantifying the Proteolytic Release of Extracellular Matrix-Sequestered VEGF with a Computational Model

BACKGROUND: VEGF proteolysis by plasmin or matrix metalloproteinases (MMPs) is believed to play an important role in regulating vascular patterning in vivo by releasing VEGF from the extracellular matrix (ECM). However, a quantitative understanding of the kinetics of VEGF cleavage and the efficiency of cell-mediated VEGF release is currently lacking. To address these uncertainties, we develop a molecular-detailed quantitative model of VEGF proteolysis, used here in the context of an endothelial sprout. METHODOLOGY AND FINDINGS: To study a cell's ability to cleave VEGF, the model captures MMP secretion, VEGF-ECM binding, VEGF proteolysis from VEGF165 to VEGF114 (the expected MMP cleavage product of VEGF165) and VEGF receptor-mediated recapture. Using experimental data, we estimated the effective bimolecular rate constant of VEGF165 cleavage by plasmin to be 328 M(-1) s(-1) at 25 degrees C, which is relatively slow compared to typical MMP-ECM proteolysis reactions. While previous studies have implicated cellular proteolysis in growth factor processing, we show that single cells do not individually have the capacity to cleave VEGF to any appreciable extent (less than 0.1% conversion). In addition, we find that a tip cell's receptor system will not efficiently recapture the cleaved VEGF due to an inability of cleaved VEGF to associate with Neuropilin-1. CONCLUSIONS: Overall, VEGF165 cleavage in vivo is likely to be mediated by the combined effect of numerous cells, instead of behaving in a single-cell-directed, autocrine manner. We show that heparan sulfate proteoglycans (HSPGs) potentiate VEGF cleavage by increasing the VEGF clearance time in tissues. In addition, we find that the VEGF-HSPG complex is more sensitive to proteases than is soluble VEGF, which may imply its potential relevance in receptor signaling. Finally, according to our calculations, experimentally measured soluble protease levels are approximately two orders of magnitude lower than that needed to reconcile levels of VEGF cleavage seen in pathological situations

Synthesis and Self-Assembly of Well-Defined Block Copolypeptides via Controlled NCA Polymerization

This article summarizes advances in the synthesis of well-defined polypeptides and block copolypeptides. Traditional methods used to polymerize α-amino acid-N-carboxyanhydrides (NCAs) are described, and limitations in the utility of these systems for the preparation of polypeptides are discussed. Improved initiators and methods that allow polypeptide synthesis with good control over chain length, chain length distribution, and chain-end functionality are also discussed. Using these methods, block and random copolypeptides of controlled dimensions (including molecular weight, sequence, composition, and molecular weight distribution) can now be prepared. The ability of well-defined block copolypeptides to assemble into supramolecular copolypeptide micelles, copolypeptide vesicles, and copolypeptide hydrogels is described. Many of these assemblies have been found to possess unique properties that are derived from the amino acid building blocks and ordered conformations of the polypeptide segments. © Springer-Verlag Berlin Heidelberg 2013

Navigating the Museum

A visit to a museum is generally a welcome treat. As we experience a museum our brain constructs its own internal museum of the mind to help us navigate, explore, and form the memories we live our lives by. This process is fundamentally guided by the architecture of the space and its influence on our perceptions and expectations. In this chapter we will present recent discoveries of how the brain represents and remembers space and use this understanding to create a starting point for a journey we are beginning; the relation of architecture to neuroscience