Aristotle started the ball rolling. Our ideas about gravity have
evolved ever since. We will take a whirlwind tour of how theories of
gravity have changed as our mathematical technique, observations,
theoretical sophistication, and society have changed. Far from being
settled, this most obvious of natural forces is anything but well
understood.
January 30, 2018
Stochastic optimization: Making complex design, planning, and
operation decisions in the face of uncertainty
Jim Luedtke, UW Department of Industrial Engineering
Stochastic optimization is a branch of mathematical optimization
concerned with helping make design, planning, and operation
decisions in the face of uncertain outcomes or data. Example
applications of stochastic optimization include: planning power
generation in systems with uncertainty in wind outputs and rainfall
(which effects hydro-reservoir levels); deciding order quantities at
a retailer with uncertain customer demands; and making financial
investments without knowing the returns the different investment
options will yield. I will provide an overview of the field
stochastic optimization, with a bias towards topics related to my
research. I will focus on discussing different types of models
and when they might be useful, and, time permitting, will overview
some of the solution approaches.
February 6, 2018
Prions and the environment
Joel Pedersen, UW Department of Soil Science
Prions are the enigmatic etiological agents of transmissible
spongiform encephalopathies (TSEs), a class of fatal
neurodegenerative diseases affecting humans and other mammals. The
pathogenic prion protein is a misfolded form of the host-encoded
prion protein and represents the predominant, if not sole, component
of the infectious agent. Environmental routes of TSE transmission
are implicated in epizootics of sheep scrapie and chronic wasting
disease of deer, elk, and moose. Soil is the most plausible
candidate for preserving prion infectivity in the environment. We
have investigated prion attachment to and detachment from inorganic
and organic soil particle surfaces and examined the effect of
association with specific soil constituents on disease transmission.
Interaction of prions with some phyllosilicate mineral surfaces is
remarkably strong. Interestingly, rather than diminishing
bioavailability, attachment to such particles enhances disease
transmission. This finding suggests an explanation for environmental
disease transmission despite the presumably low levels of prions
shed by infected animals. Our results to date suggest that prions
released into many soil environments are preserved near the surface
in a bioavailable form, likely perpetuating prion disease epizootics
and exposing other species to the infectious agent. The high
stability of prions observed in other contexts may contribute to
their survival in the natural and engineered environments.
February 13, 2018
Complexity in gene editing outcomes with defined CRISPR
nanoparticles
Kris Saha, UW Department of Biomedical Engineering
Writing specific DNA sequences into the human genome is challenging
with gene-editing reagents, since most of the edited sequences
contain various imprecise insertions or deletions of DNA sequence.
Only a minor of sequences produced contain the desired sequence. We
developed a modular RNA aptamer-streptavidin strategy, termed
S1mplex, to complex CRISPR-Cas9 ribonucleoproteins with a nucleic
acid donor template. In human cells, tailored S1mplexes increase the
ratio of precisely edited to imprecisely edited alleles up to
18-fold higher than standard gene-editing methods, and enrich cell
populations containing multiplexed precise edits up to 42-fold.
Topics related to the complexity seen in the sequence outcomes will
be discussed. Advances in reducing the complexity of sequence
outcomes could greatly reduce the time and cost of in vitro or ex
vivo gene-editing applications in precision medicine and drug
discovery and aid in the development of increased and serial dosing
regimens for somatic gene editing in vivo.
February 20, 2018
Kim Krautkramer, Wisconsin Institutes for Discovery
Interactions between environment and host epigenome: metabolism, the
microbiota, and hibernation
How do environmental stimuli/insults signal to the mammalian
epigenome and what role do the microbiota play in this process?
This talk will highlight recent and ongoing collaborative work
aimed at understanding how environmental factors impact the host
epigenome in mammals, including diet, maternal environment, and
seasonal changes in body composition and metabolism in
hibernators. We explore these questions using a variety of
methods, including mass spectrometry, high throughput sequencing,
and both wild-caught and gnotobiotic animal models.
February 27, 2018
Thoughts on drumlins, a major component of Wisconsin's glacial
landscape
David Mickelson, UW Department of Geology
Thousands of cigar-shaped elongate hills dominate the landscape to
the east and north of Madison. Produced by glaciers 15,000 to 25,000
years ago, they have a range of heights from meters or less to
several hundred meters and have distinctly different length-to-width
ratios in different areas. All are parallel to former ice flow
direction. They are composed of sediments deposited by the last
glaciation, but many also contain older deposits. Why are they so
abundant in Wisconsin, but absent from the huge areas covered by the
last glaciation in most of Illinois, Indiana, Iowa, and Ohio?
March 6, 2018
Wada basins and distributed fields of determination
Steve Ridgely, UW Department of Asian Languages and Cultures
Wada Basins are spaces containing three or more subregions in which
each boundary is shared by all subregions. This topological concept,
attributed to Takeo Wada and described by his Kyoto University
colleague Kunizō Yoneyama in 1917, has gained an afterlife through
application to complex systems in which a “basin” of initial
conditions might be said to exhibit the “Wada property.” The
topological form of a Wada basin would seem to map determination
across a distributed field such that indeterminacy would be inherent
to the spatial form, well beyond a metaphor for systems about which
we have insufficient information.
March 13, 2018
Speech as a dynamical system
Ben Parrell, UW Department of Communication Sciences and Disorders
The act of speaking is one of the most complex motor behaviors
humans produce: a set of over 100 muscles must be precisely
coordinated in space and time to produce rapid movements (50-300 ms)
at a high rate (roughly 40 unique sounds per second). How can we
control such a complex system with enough precision to produce
intelligible speech? This talk will present the view that speech is
a hierarchical dynamical system, with control needed only at a
high-level (of speech goals or tasks) rather than a system where all
muscle activations are controlled centrally. I will explain how this
approach can explain speech phenomena in various languages, and show
a preliminary sketch of how such a system could be instantiated in
the brain.
March 20, 2018
What makes math hard? Hint: It’s not the math
Mitchell J. Nathan, UW School of Education
I present findings on mathematical intuitions and invented
solution strategies to challenge
well-entrenched notions that mathematics is hard to learn.
I consider how Expert Blind Spot shapes the framing of
Math-As-Hard that can alienate learners from entering
a field of great creativity and enormous societal relevance,
and I challenge the audience to reflect on who benefits from
this framing (look around the room), the implications for the
future of science and public policy, and what we all
can do about it.
April 3, 2018
The invention of public radio at the UW--Madison Physics Department,
1917-1919
Jim Reardon, UW Department of Physics
From April 1917-March 1919 Prof. Earle Terry of the UW-Physics
Department was able to continue research in wireless voice
telephony--what we would now call AM radio--while all through the
rest of the world, non-military radio research was halted by World
War I. By the end of this time, he and graduate student Cyril Jansky
were able to make triode vacuum tubes capable of dissipating more
than 50 W, allowing his station 9XM to transmit voice intelligible
at a range of 130 miles. Terry and Jansky freely shared their work
with researchers at other Universities, which contributed to the
proliferation of College and University radio stations in the
1920's, the ancestors of what we now know as public radio. The talk
will feature a replica of the original 9XM transmitter, constructed
as part of the celebration of the centennial of the Ingersoll
Physics Museum.
April 10, 2018
Cloud quantum computing
Maxim Vavilov, UW Department of Physics
In this talk I will describe the IBM quantum processor that is
open to the public. The processor has only 5 qubits, but is suitable
for quantum demonstrations of basic qubit gates, Bell
inequality experiments and elements of quantum error correction.
I will review the web-based interface for writing programs for
the quantum processor. Then, I will demonstrate the execution
of several programs and discuss the accuracy of the results obtained
from experiments. I will also review recent progress towards a
large-scale universal quantum processor.
April 17, 2018
Are modern psychological and social behavior investigators missing a
boat developmental neuroscience could help them catch?
Bernard Z. Friedlander, Department of Psychology, University of
Hartford
Large bodies of research with people of all ages tend to confirm
that children who perform better on tests of delayed gratification
(DG) tend to do well in life, while those with limited capacities
for DG as children do less well in the progress of their lives.
This paper presents the possibility that DG and related behavioral
realities represent critical processes in individual psychological
development. These processes are open to new vectors of
understanding based on new thinking about the autonomic nervous
system and developmental neuroscience. New ways of thinking about
old problems offer tantalizing possibilities for new research.
The postgenomic era has been ongoing for some time, depending on
whom one asks. This talk will discuss several fields that developed
with the aim to complexify the reductionism of genetics. I
earlier wrote about systems biology and developmental systems
theory. Developmental Systems Theory (DST) developed in negative
response to the genetic reductionism of early genetics rhetoric and
theoretical approaches. Systems biology developed in positive
response to the vast territories of information produced by the
genome sequencing projects, what we now call “big data.”
Sociologists have studied systems biology and epigenetics as
hoped-for avenues to operationalize DST and complexity.
Epigenetics has recently been proclaimed to be the solution to
difficulties met by genetics and genomics in the search for health
and disease mechanisms and potential therapies. However,
epigenetics as DNA methylation at and around the genome differs
vastly from “epigenetic inheritance.” Some scholars have argued that
epigenetics is producing reductive explanations such as “blame the
mother,” that emulate genetic reductive explanations. This
talk will discuss these in the context of our current research on
epigenetics and systems biology.
May 1, 2018
Year-end celebration
Following the tradition of recent years in which we had a delightful
discussion of where we have come and where we might go with the
seminars, this last seminar of the semester will be devoted to a
continuation of that discussion without any formal speaker. We will
also discuss what we want to do during our informal weekly lunches
on the Memorial Union Terrace which begin on May 8th. This
celebration will include expanded refreshments, to which your own
culinary contribution is welcome.