Integrated Calendar

A major objective of neuroscience is to understand the neural code, namely how the patterns of neuronal signals (e.g. action potentials, membrane potential, calcium concentrations) “represent” physical objects, commands for actions, or psychological phenomena. An successful neural coding scheme has to be robust to noise (i.e. random neuronal activity). We have recently shown that using a small perturbation, an introduction of one “extra”-spike to the activity of a single neuron in the cortex, and studying the consequence of that perturbation we can obtain bounds on the level of noise in the cortex. Theoretical analysis of the data indicates that intrinsic, stimulus-independent variations in membrane potential of cortical neurons are on the order of 2.2–4.5 mV—variations that are pure noise, and so carry no information at all. Such level of noise places severe limitations on the plausibility of neural code based on precise spike timing. Using recent advances in optogentics we can extend the approach of introducing a precisely controlled perturbation. We explore how these perturbations affect the dynamics of activity in the cortex as well as theirs effect on animal performance on a task, to gain further bounds and insights on the neural code.

Contemporary artistic realizations elicit interest and excitement by controlling and projecting evolving coherent and chaotic patterns in varying space and time domains. Stemists ( STEM* people ) research to quantify and model and understand the underlying physics, chemistry and biology of the associated fluid and wave motions.

Historically, Leonardo da Vinci (1452 –1519,) the Renaissance man ( i.e.sketcher, painter, sculptor, scientist, engineer, inventor, anatomist, writer and more) was the first to sketch and paint images across STEM disciplines. His deep appreciation of vortex-and-turbulence fluid dynamics in diverse fluid environments is uncanny and he may be considered the "father" of flow visualization.

I will illustrate the approach of artists from the 19th-21st centuries who are intrigued by flow and stemists researching fundamental and technological fluid processes. Stemists regularly apply visualization-and-quantification ( "visiometric" [1] ) modes to explore ever-increasing amounts of data from laboratory experiment, remote observation and numerical simulation. The beauty resides in the ability of direct and projected colored images, animations and installations to: reveal truth; experience joy through understanding; and inspire viewers ( particularly youth, and including their educational process ).

Two of many forward looking contemporary fluid-kinetic artists include:
• Shinichi Maruyama , high-speed kinetic-fluid experimenter and photographer at http://shinichimaruyama.com/.
• Ned Kahn, at http://nedkahn.com.
Ned's many pioneering “… artworks frequently incorporate flowing water, fog, sand and light to create complex and continually changing systems. …I am intrigued with the way patterns can emerge when things flow… they are patterns of behavior - recurring themes in nature" ( from his 2003 MacArthur Award talk at his URL given above).

His works have been increasingly well-received around the world, most recently at Singapore's magnificent Marina Bay Sands urban forum and living center. Here we have the first major embedded "ArtScience" museum and three of Kahn's large kinetic-fluid installations:
• "Wind Arbor" where a centrally located wind-driven vertical wall, exhibits randomly changing patterns;
• "Rain Oculus", where a large swirling whirlpool at street level falls thru an indented circular hole;
• "Tipping Wall" where water at the top falls onto rows of mounted and pivoting rectangular plates and causes them to engage in a dance of chaotic oscillations .
These words hardly convey the unusual imagery and sounds to be seen in situ or in videos of these fluid dynamical environments [2].
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* Stemist: A practitioner from Science, Technology , Engineering or Mathematics who uses contemporary visualization and quantification techniques to enhance and communicate their work.

========================REFS for May 29 2012===============
[1]. "DAVID and Visiometrics: Visualizing and quantifying evolving amorphous objects" F.J. Bitz and N.J. Zabusky, Computers in Physics, Nov/Dec 1990 (603-614). Also,
"Visiometrics, Juxtaposition and Modeling". Norman J. Zabusky, Deborah Silver, Richard Pelz, and Vizgroup. Physics Today. 46, Issue 3, March 1993, p. 24, h

[2]. "Wind Arbor, Rain Oculus and Tipping Wall:The Art of Ned Kahn at Marina Bay Sands, Singapore" . Video narrated by chief-architect, Moshe_Safdie http://www.youtube.com/watch?v=lVwS7reOhX8&feature=player_embedded.

Amorphous solids, polymers, and disordered lattices show striking qualitative and quantitative similarities of e.g. their specific heat, thermal conductivity, and internal friction at temperatures below 3K This suggests the existence of a mechanism intrinsic to the disordered state of matter that dictates physical properties at low temperatures. The standard model within which this problem is treated is that of tunneling two-level systems (TLSs), introduced long ago by Anderson Halperin and Varma, and Phillips. Yet, key questions such as the nature of the TLSs, the mechanism dictating universality, and the energy scale dictating the range of the universal regime, are not yet understood. We propose here a model of two types of TLSs, (nearly) symmetric, and asymmetric with respect to inversion symmetry. The former interact weakly with the phonon field, yet gap the latter at low energies. Our model explains well the above and other puzzles related to universality, and may prove useful in treating other problems where TLSs play a crucial role, such as 1/f noise, ageing in glasses, and superconducting qubit decoherence.