Mathematical Application Seminar*
Fall 2009 Spring 2010
Tuesdays 2 3 pm
Monroe Hall,
Organizer: E. Arthur Robinson and Yongwu Rong
May 6, 2010, Thursday 11:45 4 pm
Monroe Hall, Room B32
For directions, check
GWU campus map. Select Foggy Bottom
campus.
Schedule
11:45 12
noon. Refreshments
12 12:45
pm. Keynote Lecture
Xiaofeng Ren, Department
of Mathematics,
Title:
Ansatz solutions of a curvature-potential
equation from morphology and mophogenesis problems.
Abstract:
See below.
12:45 1pm. Break
1 2pm
Cristian Tomasetti, Department
of Mathematics,
Title:
A stem cell clonal expansion with mutations.
Hosam Mahmoud, Department
of Statistics,
Title:
Phases in urn models for the mixing of gases.
Title:
Self-dual graph embeddings and their connection to percolation theory.
2 2:15pm. Break.
2:15
3:15pm
Wei Cheng, Department of
Computer Sciences,
Title:
Multipath Maintenance in Many to One Wireless Sensor Networks.
Guanyu Wang, Department of Physics,
Title:
Logical based reverse network
engineering reveals backbone motif structure in biomolecular
networks.
E. Arthur
Robinson, Department of Mathematics, George Washington University.
Title:
Some remarks about Boolean networks from the dynamical systems point of
view.Some remarks about Boolean networks from the dynamical
systems point of view.
3:15
3:30pm. Break.
3:30 4pm
Jagdish Chandra, Department of Statistics,
Title: Dynamic Models of Social
Networks.
Informal
discussion.
Abstracts:
Ansatz solutions of a curvature-potential
equation from morphology and mophogenesis problems.
Xiaofeng
Ren, Department of Mathematics,
Abstract: Pattern formation problems arise in many physical and
biological systems as orderly outcomes of self-organization principles.
Examples include animal coats, skin pigmentation, and morphological
phases in block copolymers. Recent advances in singular perturbation
theory and asymptotic analysis have made it possible to study these
problems rigorously. In this talk I will discuss a central theme in the
construction of various patterns as solutions to some well known PDE and
geometric problems: how a single piece of structure built on the entire
space can be used as an Ansatz to produce a near
periodic pattern on a
bounded domain. We start with the simple disc and show how the spot
pattern can be mathematically explained. More complex are the ring
structure and the oval structure which can also be used to construct
solutions on bounded domains. Finally we discuss the newly discovered
smoke-ring structure and the toroidal tube structure
in space. The
results presented in this lecture come from joint works with Kang,
Kolokolnikov, and Wei.
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April 5, 2010, Monday 4
5 pm (note the unusual time / room)
Speaker: Seth Sullivant,
Department of Mathematics, North Carolina State University
Title: Identifiable Gaussian Graphical Models
Place: Monroe 113, 2115 G Steet.
Abstract: A Gaussian graphical model is a statistical model
that uses a
graph to encode linear relationships between a collection
of random
variables. These linear relationships determine a positive
definite
covariance matrix whose entries are polynomials in certain
parameters
associated to the edges of the graph. The edge parameters are
identifiable
if they can be recovered from the covariance matrix. I
will discuss recent
results, where we employ techniques from computational algebra
and
algebraic combinatorics to make
progress on the identifiability problem.
This is joint work with
Mathias Drton, Rina Foygel, Luis Garcia, and Sarah
Spiegelvogel.
Biography: Seth Sullivant's research
interests are in algebraic statistics and, more
generally, in using algebraic geometry as a tool in applied
mathematics.
He received his Ph.D. from
UC Berkeley in 2005, and was a Junior Fellow at
Harvard University from 2005
- 2008. Currently he is an Assistant
Professor of
Mathematics at
several Noble prizes, including the Packard Foundation
Fellowship in Science and Engineering.
http://www.packard.org/newsDetails.aspx?RootCatID=2&CategoryID=48&ItemID=4797
November 24, 2009,
Tuesday 2 3 pm
Speaker: Huzefa Rangwala, Computer Science/Bioinformatics,
George Mason University
Title: Interactions using Kernel-based Methods.
Place: Monroe Hall, 2115 G Street, Room 267
Abstract: Proteins have a vast influence on the
molecular machinery of life.
Stunningly complex networks of proteins perform innumerable functions
in every living cell. Knowing the three-dimensional structure of
proteins is crucial to advances in biology, as this information
provides insight into how proteins operate. For example, structural
information enables function prediction, the identification of other
interacting biomolecules (e.g., proteins, DNA and
RNA), and the
rational search for ligands that can be used to
enhance or inhibit
these interactions.
In this talk I will highlight my work involving use of sequence
information to characterize the structural and functional nature of
proteins. I will introduce the notion of pairwise
kernels to study
protein-protein interactions, and finally talk about an application
towards drug discovery.
Biography:
Huzefa Rangwalas research
interests include bioinformatics, machine
learning, and high performance computing. His research has resulted in
the development of software packages for performing protein sequence
classification (kernel-compute), predicting local structure and
functional properties (svmPRAT, MONSTER, TOPTMH).
Recently, he has
been involved in development of methods for integrating information
from heterogeneous data, learning from unlabeled instances, and
multi-label classification within the context of chemical and
biological data. He has also started developing a prototype for
fragment assembly for high throughput short reads. He got his PhD from
the University of Minnesota in 2008.
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November 17, 2009,
Tuesday 2 3 pm
Speaker: Tim McCaffrey, Medical Center, GWU
Title: The evolution of massively parallel sequencing methods: Opportunities for mathematical and statistical modeling.
Place: Monroe Hall, 2115 G Street, Room 267
Abstract: The sequencing of the human genome was
transformational for biomedical research, but provided only a single template
to overlay diverse types of experimental data. The recent technological advances in massively parallel sequencing allows scientists
to acquire new genomes in a matter of days, not years. Future discovery will
require new mathematical and statistical techniques to process and display
terabytes to petabytes of sequence information within
a highly integrated software environment. The opportunities and challenges for
transforming human health will be discussed.
November 10, 2009,
Tuesday 2 3pm
Speaker: Guanyu Wang, Department of Physics, GWU
Title: Computational complexity in Boolean networks
Place: Monroe Hall,
Abstract: We recently developed a logic-based approach for
investigating
the structure-function relationship of biomolecular networks.
In this talk, I will briefly
review the approach and then discuss
the computational complexity in some aspects of the
algorithm.
I will show the connection
between our algorithm and the well-known
set covering problem in computer science. I will prove
that finding
a minimal network (an important concept in our
approach) is
equivalent to the minimal set covering problem, which is
NP-hard.
Some perspective from the
approach will also be addressed.
November 3, 2009, Tuesday
2 3pm
Speaker: Hao Chen, Department of Physics, GWU
Title: The Structure of the Solution Space of the Strong Inhibition
Model
Place: Monroe Hall, 2115 G Street, Room 267
Abstract: The central task of the system biology is to understand the
biology process. During the past decade, various models have been proposed and
studied. Among them, the strong inhibition model is very simple and successful.
In this talk we will discuss the solution structure of the model.
Previous Seminars
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* The
Mathematical Application Seminar is currently sponsored by the George Washington University Seminars program.
It also
received support the Department of
Mathematics at the George Washington University.
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