Integrated Calendar

A few nanometer thin interface which is formed between the metal and the organic structure controls bonding strength, stability and charge transfer between these two quite different types of materials. To understand and optimize formation of that interface at the nanoscale we used Self-Assembled Monolayers (SAMs) which are considered a model system for the analysis of the interaction of organic molecules with the metal substrate. In this presentation we will focus on application of a new experimental approach based on ion beam-induced desorption which we used to address this problem demonstrating for the first time the effect of oscillations in stability of consecutive chemical bonds at the molecule-metal interface. As a next step we will analyze the consequence of this effect for the thermal stability of a model SAM systems and, finally, we will discuss how this effect can contribute to the charge transport at the molecule-metal interface

Driven by recent technological advancements, behavior and brain activity can now be measured at an unprecedented resolution and scale. This “big-data” revolution is akin to a similar revolution in biology. In biology, the wealth of data allowed systems-biologists to uncover the underlying design principles that are shared among biological systems. In my studies, I apply design principles from systems-biology to cognitive phenomena. In my talk I will demonstrate this approach in regard to creative search. Using a novel paradigm, I discovered that people’s search exhibits exploration and exploitation durations that were highly correlated along a line between quick-to-discover/quick-to-drop and slow-to-discover/slow-to-drop strategies. To explain this behavior, I focused on the property of scale invariance, which allows sensory systems to adapt to environmental signals spanning orders of magnitude. For example, bacteria search for nutrients, by responding to relative changes in nutrient concentration rather than absolute levels, via a sensory mechanism termed fold change detection (FCD). Scale invariance is prevalent in cognition, yet the specific mechanisms are mostly unknown. I found that an FCD model best describes creative search dynamics and further predicts robustness to variations in meaning perception, in agreement with behavioral data. These findings suggest FCD as a specific mechanism for scale invariant search, connecting sensory processes of cells and cognitive processes in human. I will end with a broader perspective and outline the benefits of the search for computational design principles of cognition.

Mixing semi-dilute solutions of oppositely charged polyelectrolytes generally yields compositions spanning complexes (solid) to coacervates (elastic liquid) to dissolved solutions with increasing salt concentration. In this work we show how to form a strong network of oppositely charged polyelectrolytes by using an interplay of hydrogen, hydrophobic, and electrostatic interactions.