Madison Chaos and Complex Systems Seminar

Fall 2005 Seminars

All seminars are Tuesday at 12:05 pm in 4274 Chamberlin except as noted.

Short List

Abstracts

September 6, 2005

The resources of planet Earth and oil in particular

C. S. Clay, UW Department of Geology and Geophysics
Many of us who do geology and geophysics are aware of the nature of the resources that we-people use. Since beginnings of organized populations and agriculture some 13 000 yeas ago, people have used the land to support them and their children. Some climatologists suggest that global warming could have started then. "The optimist proclaims that we live in the best of all possible worlds: and the pessimist fears this is true". J. B. Cabell (1926). Today, oil runs our systems and controls our lives. Katrina gave us a little oil shock at the gas station.

Back a little more than 3 decades, the National Academy of Sciences-National Research Council published "Resources and Man" (Freeman and Company, 1969). The section, " 8/Energy Resources" by M. K. Hubbert, gives an analysis of energy resources. Coal , lignite, petroleum, and water power are included in his chapter. He compares the Zapp hypothesis (one used by some economists) with actual oil discovery data. The Zapp prediction is orders of magnitude too large. Hubbert estimates the US (lower 48 states) peak to be about 1970. This peak is at the center of 80% of the production with the duration of about 65 years. Kenneth Deffeyes revisited Hubbert's research and put an extension to the world in his book "Hubbert's Peak" (2001).

The petroleum deposits in Saudi Arabia have been the major supply for the world since the 1950's. Matthew R. Simmons has collected much data on the Aramco - Saudi Arabia oil situation in a book "Twilight in the Desert" Wiley (2005). From the Capitol Times, 9-3-05 and a review D. R. Baker:--- "For example Saudi Arabia, the global economy's gas tank, might not have the vast petroleum reserves its leaders claim, according to a new book rattling the energy industry." --- I believe that Simmons' book is consistent with Hubbert and Deffeyes. We may be on a decline of world wide reserves.

The petroleum companies do not want to admit they have limited reserves because their stock values could nose dive.


September 13, 2005

The biology of stress, fear, and anxiety

Ned Kalin, UW Department of Psychiatry

Stress is common, and we are always finding ourselves in stressful situations. We all handle our responses to stressful situations differently with some of us being relatively unaffected whereas others can become overwhelmed. Stress also is a frequent precipitant of psychopathology, like anxiety and depressive disorders. The biology underlying the stress response and how it relates to fear, anxiety, and depression will be discussed with emphasis on the brain circuitry that mediates these responses. Emphasis will also be placed on early developmental factors that confer either risk or resilience in developing individual differences related to the stress response and the development of psychopathology.


September 20, 2005

How plants remember winter

Rick Amasino, UW Department of Biochemistry

Certain species of plants have the remarkable ability to measure a complete winter season of cold and to 'remember' this prior cold exposure in the spring. Plants use this ability to distinguish the prolonged cold of winter from short cold spells in autumn and thus ensure that processes such as flowering and the release of bud dormancy occur only in the spring. I will discuss our work on how this memory system in plants operates at a molecular level.


September 27, 2005

Dynamics of competitive, cooperative and monotone systems

Morris W. Hirsch, UW Department of Mathematics and University of California, Berkeley

This talk concerns dynamical systems that as time increases preserve a (partial) order relation on the state space, such as the vector order in Euclidean space, or the natural order on a space of real-valued functions. These occur in population dynamics, epidemiology, economics and other fields. Examples in ordinary differential equations (ODEs) include the reversed-time flow in an attractor for a competitive Lotka-Volterra ODE; and in partial differential equations, in nonlinear heat equations. There are also discrete-time analogs. The main feature of such systems is that they tend to be non-chaotic: Under mild assumptions on such it can be proved that the trajectory of almost every initial state converges to a stable fixed point. In an attractor every orbit is nowhere dense, and the union of the periodic orbits is nowhere dense. There are no attracting limit cycles.


October 4, 2005

Leverage in complex systems

Mark Finster, UW School of Business

This seminar examines seven common approaches used by organizations to discover areas of focus where resources can be allocated for organizational change. These schools of thought include communication theory, stratification, structure and flow analysis (e.g., reengineering), cost-value analysis, theory of constraints, analysis of statistical variation and systems theories. Examples in business, government and non-profits (health care) will be provided.


October 11, 2005

Intelligent design

Elliott Sober, UW Department of Philosophy

Evolutionary biologists sometimes criticize creationism (or the theory of intelligent design) by saying that it is disconfirmed by the imperfect adaptations we observe in nature.  Here I develop a different criticism -- that intelligent design theory makes no predictions at all.  This criticism is independent of whether contemporary evolutionary theory
is adequate.

For further information, see The Design Argument.


October 18, 2005

A physicist's brain

Clint Sprott, UW Department of Physics

The human brain is perhaps the most complex object in the entire Universe, capable of remarkable feats. Although much progress has been made in understanding its composition and operation, much about it remains a mystery. This talk will describe a very simple model of the brain that, like a digital computer, is capable of universal computation, in principle solving any problem with the right program. The model brain behaves chaotically, following definite rules, but exhibiting a degree of unpredictability and novelty. A program (p-brain) will be demonstrated and trained in real time to produce aesthetically appealing visual art, many examples of which will be shown.

This talk is available as a PowerPoint Presentation.


October 25, 2005

The brain through the eyes of autism: Gaze-fixation, face processing and brain function in autism and fragile X syndrome

Kim Dalton, UW Waisman Center

Autism is a pervasive developmental disorder associated with moderate to severe deficits in social/emotional processes.  Inattention to faces is a developmentally primary symptom of autism that is apparent by the age of one year and is associated with delays in early, face-related milestones, such as looking to another person’s face to reference that person’s reactions or to share their own experiences.   Gaze aversion, social withdrawal and deficits in emotion and face processing continue through out the life span as hallmark characteristics of autism.  Converging evidence suggests that the social/emotional deficits associated with autism have their basis in dysfunction of areas of the brain associated with social/emotional processes, suggesting that autism is a disorder of the “social brain”.   Specifically, our results suggest that differences in gaze-fixation and face processing are associated with abnormalities in the central circuitry of emotion and emotion regulation leading to heightened sensitivity and over arousal to social/emotional stimuli in autism.  Our current research is designed to extend our findings of abnormalities in the brain circuitry of emotion and emotion regulation during emotional face and voice processing and integration in individuals with autism using state-of-the-art eye-tracking and brain imaging techniques.  In addition we are broadening our subject populations to include other developmental disabilities associated with autism such as fragile X syndrome.


November 1, 2005

Cortical effective connectivity across states of vigilance in humans

Marcello Massimini, UW Department of Psychiatry

When awakened early in the night from deep non rapid eye movements (NREM) sleep, people often report little or no conscious experience. It was first thought that this fading of consciousness was due to the brain shutting down. However, while metabolism is reduced, the thalamocortical system remains active, with mean firing rates close to those of quiet wakefulness. Moreover, coherent or synchronized activity continues to be detected among distant cortical areas (3, 4), and sensory signals still reach the cerebral cortex. Why, then, does consciousness fade?

According to a recent proposal, consciousness depends critically not so much on firing rates, synchronization at specific frequency bands, or sensory input per se, but rather on the brain’s ability to integrate information, which is contingent on the effective connectivity among functionally specialized regions of the thalamocortical system. Effective connectivity refers to the ability of a set of neuronal groups to causally affect the firing of other neuronal groups within a system. The fading of consciousness in deep NREM sleep should then be associated with an impairment of cortical effective connectivity. To test this prediction, we employed a combination of navigated transcranial magnetic stimulation (TMS) and high-density electroencephalography (hd-EEG). This is a novel approach developed to measure the brain response to the direct perturbation of a chosen cortical region non-invasively and with good spatiotemporal resolution.

We delivered low frequency (<1 Hz) TMS together with masking noise while subjects (n=6) lied on a reclining chair. An infrared positioning system and a 60-channel TMS-compatible EEG amplifier were used to target precisely and reproducibly the cortical region of interest while recording TMS-evoked potentials over the entire scalp. In some subjects, different areas (both frontal and parietal) were stimulated during separated sessions. In each subject, we calculated the strength and the spread of cortical evoked activity by solving the inverse problem on a realistic head model. We also analyzed evoked activity on a single trial basis. All subjects progressed from wakefulness to slow wave sleep while stimulation was delivered. Consistently, TMS evoked a series of high-frequency oscillations (15-45 Hz) during wakefulness while, during sleep, the same stimulation elicited a higher amplitude, slower component. This changes in cortical responsiveness were also evident on a single-trial basis during transition between behavioural states. In all subjects, source modelling of the average response revealed the presence of recurrent cortical activations that propagated amongst anatomically connected cortical regions during wakefulness. During sleep, an initially stronger cortical activation progressively dissipated while remaining localized.

Compared to wakefulness, the reaction of the sleeping brain to a direct cortical perturbation is initially stronger, but remains local and is not sustained over time. These changes possibly reflect a substantial decrease of cortico-cortical effective connectivity and may underly the fading of consciousness during NREM sleep.


November 8, 2005

Can, how can we predict the future?

C. S. Clay, UW Department of Geology and Geophysics
John Young, UW Department of Atmospheric and Oceanic Sciences

Starting in the 1920's, geophysicists-seismologists used seismic waves to "image" the subsurface structure of the Earth. By the  1950's, exploration seismology became a rather well defined region for research. Discovery of oil bearing formations enriched the oil companies. As interpreted by geophysicists, seismic records were much better at finding oil than "divining rods". The skill of an interpreter began to look a little like the intuition of a diviner. We needed a objective method to identify the reflections from interfaces in the subsurface structure in the presence of many other wiggles on the paper records.

In 1942, Norbert Weiner produced a monograph, Extrapolation, Interpolation and Smoothing of Stationary Time Series. Doing the calculations was a challenge then. Several of the geophysical students at MIT recognized that Weiner's method could be a powerful tool for identify the structural interfaces. They started doing time series analysis. Enders Robinson summarizes use of digital expressions of the geophysical signals in Multichannel Time Series Analysis with Digital Computer Programs(1967) and revisions. In exploration geophysics, the book of Enders Robinson and Sven Treitel, Geophysical Signal Analysis (1980) gives a practical summary. G.E.P. Box and G. M. Jenkins, Time Series Analysis Forcasting and Control (1970) is a text on digital methods. Much of this work was done before the Apple II, simple-robust programing languages and MatLab.

These the least squares prediction-error filters were created with the assumption that the time series were stationary. Question: Are the climate and economic time series stationary, are they Mandelbrot fractal like or a little of both? A simplified derivation is Clay's Elementary Exploration Seismology (1990),Section B1.5.

Given: signal x and length N, find the least squares optimum filter f that predicts the value p at its next time step of x. Does the difference between the signal x and the prediction p display something unexpected?


November 15, 2005

Antievolution in America:  From creation science to intelligent design

Ron Numbers, UW Department of History of Medicine

Scarcely a day goes by without some account appearing in the news about the progress of creationism or intelligent design.  As readers of the New York Times and watchers of "The Daily Show" know, these issues have become a topic of both concern and comedy.  Is intelligent design simply creationism dressed up in fancy clothes, or is it a revolutionary scientific breakthrough, rivaling (as its proponents maintain) those of Newton, Lavoisier, and Einstein?  Does it deserve a respectful hearing, perhaps even a place in the science curriculum, or should it be dismissed as pseudo-science?


November 22, 2005

Synaptic inhibition and neuronal oscillations studied in gene-targeted mice

Bob Pearce, UW Department of Anesthesiology

The function of neuronal oscillations remains mysterious. Early EEG recordings revealed that different frequencies emanate from different brain regions, and that their properties vary with behavioral state and are altered by drugs that interfere with cognitive function. But, the specific functions that these oscillations provide, and indeed whether they serve any crucial role at all or are simply epiphenomena, are subjects of intense interest and debate. To address these questions it will be useful to identify the cellular and molecular substrates of specific types of oscillations. Toward this end, we have used gene-targeted animals that harbor mutations in specific GABA receptor subunits to test their contributions to different types of inhibitory synapses and oscillations in the hippocampus, a brain structure that is crucial for long-term memory formation.


November 29, 2005

Questions about complexity in nature and design in science

Craig Rusbult, UW Department of Chemistry

We'll look at complexities (specified, nuclear, minimal, and irreducible) and will ask questions: If we observe a radio signal containing prime numbers (2, 3, 5, 7,...) is it logically justifiable to conclude that this is "complex specified information" and it was produced by design-directed action rather than undirected natural process? When a fine-tuning of nature causes stars to naturally produce complex nuclei (including the carbon, oxygen, and sodium in our bodies) does this indicate a universe that is intelligently designed, and/or a multiverse that overcomes improbability because in a multitude of universes almost everything will happen? What does current science indicate about the plausibility of natural chemical evolution producing a living organism, which seems to require a minimal complexity involving hundreds of biomolecules? Do some biological systems have an "irreducible complexity" that could not be produced in a step-by-step process of natural selection?

We'll also examine the methods of historical science, and will ask whether a design theory can be scientific: Can we use evidence and logic to evaluate the plausibility of theories proposing that nature was designed, or that design-directed action has occurred during the history of nature? What are the similarities and differences between operation science (to study what is happening) and the historical science (to study what has happened) in astronomy, geology, paleontology, biology, and forensics? In what ways can a design theory be consistent with the methods used in historical sciences? Logically and sociologically, how should we analyze the relationships between theories proposing design and creation? What are the interactions between scientific evaluation and philosophical interpretation? When scientists ask questions about complexity and design, is proof possible? And should we ask the questions?

This talk is available as a PowerPoint Presentation.


December 6, 2005

Lake-ice phenologies: Temporal and spatial patterns in a simple observation of nature.

John Magnuson, UW Department of Zoology

The dates that ice covers a lake in early winter and breaks up in spring are simple observations requiring no instrumentation to collect. The observations have been made around the world and in some cases for more than 100-150 years. The records reveal complex temporal and spatial patterns in slopes and in inter-annual dynamics. That the records seem to integrate seasonal data may be one of its strengths. How best to represent the dynamics and spatial patterns in these records? What explains the dynamics and spatial patterns? What do they tell us of the world in which we live?


December 13, 2005

Images of a complex world: The art and poetry of chaos

Clint Sprott, UW Department of Physics
Robin Chapman, UW Department of Communicative Disorders

Clint will describe the mathematics behind the images and Robin will read poems about chaos from their recently published book, Images of a Complex World: The Art and Poetry of Chaos.


THE FOLLOWING TALK WAS CANCELED DUE TO ILLNESS:

Single molecule platforms for the New Biology

Dave Schwartz, UW Department of Genetics

Single molecule approaches are enabling researchers to understand mechanistic details and events that commonly evade traditional means that employ bulk analysis techniques, which intrinsically obscure valuable distributions. With some notable exceptions, the single molecule approaches currently in use are quite toilsome and very low throughput. Given the modern requirements for large and complex datasets, a critical need for high-throughput single molecule approaches has developed within the biological community. This need has emerged due to the recent appreciation of what large, complex datasets offer, when optimally interfaced with insightful analysis and experimental systems. In this regard, high-throughput, single molecule systems provide the necessary platform for whole genome analysis, which is applicable to a broad range of biological problems. High-resolution, whole genome analysis has been gaining favor because we now have the means to grapple with the complexities of "real" biological systems, both locally and in terms of meaningful populations.