News & Announcements

Previous front page features

Current Faculty Positions

Mathematics Help Room and Course Graders application

2014 Holl Mathematical Discovery Workshop for Teachers

Math + Juggling = better problem-solving tools for ISU students

ISU takes top two spots at ICMC

Kliemann named 2013 ICTM Friend of Mathematics

Department presents special session at ICTM

Pearson representatives hold help sessions for MyMathLabs

Spring 2013 Fellowship winners announced

Szemeredi named Erdos lecturer for Spring AMS meeting

Sing-Tung Yau visits department - photos

AMS invited and keynote speakers

Career Day 2012

Donald Steiner: Distinguished Alumnus Award

Hogben a finalist

Leslie Hogben is a finalist for the Academic Innovation and Leadership 2012 DuPont Pioneer Women of Innovation presentd by Techology Assication of Iowa.

Leslie Hogben: 2012 Dio Lewis Holl Chair in Applied Mathematics

MIGHTY LIII conference

Clifford Bergman: Janson Professor of Mathematics

Former grad student and professor publish co-authored paper in SIAM journal

Haseen Ahmed (2009) and Hailiang Liu have published Alternating evolution schemes fo rhyperbolic conservation laws in the SIAM Journal on Scientific Computing, Volume 33, No. 6, pp. 3210-3240.

Solutions in search of problems: Alum (former student of R. Maddux) writes in AMS Notices

Jeremy Alm (2004), assistant professor of mathematics at Illinois College, writes about the "two cultures" phenomenon.


ISU hosts STEM conference targeting secondary/post-secondary collaboration of pre-calculus teachers

The Department of Mathematics at Iowa State University will host Pre-Calculus: Three communities, One goal on campus June 7-9, 2012.

Teachers of pre-calculus and calculus as well as guidance counselors at Iowa high schools, community colleges, and Regents universities will hear from experts and will discuss ways to better prepare students to succeed in mathematics.  Students who fail or are misplaced in pre-calculus often change majors away from science, technology, engineering, and mathematics (STEM).  The conference will address means to collaborate across institutions and advance students’ understanding of key ideas in pre-calculus and calculus. 

Keynote speakers include Marilyn Carlson from Arizona State University and David Bressoud, past-president of the Mathematics Association of America from Macalester College.  Carlson, who has developed student tasks and teacher tools for teaching pre-calculus, will report on the use of the tools that results in pre-calculus students’ increased understanding of key ideas that are foundational for calculus.  Bressoud will report on the effects of the growth of the AP Calculus program as shown by his large ongoing study of calculus.  He will address the responses needed within high schools and universities.  

This conference meets the recommendations of the Governor’s STEM Advisory Council where emphasis is placed on growth and alignment of STEM education partnerships among PK-16 programs and retention of students in the STEM disciplines.

Conference resources

Teachers participating in the conference receive housing, meals, travel support, and a stipend. 
Those interested in participating should contact Heather by May 23. 


Outstanding performance by ISU Putnam team

The ISU Putnam Team of Tyler Chenhall, Kevin Moss, and Nathan Rehfuss finished 35th in this years competition.  A total of 4440 students from 572 Colleges and Universities in the United States and Canada competed.  

Tyler Chenhall ranked 102nd among all competitors and Kevin Moss ranked 276th.  

This was an outstanding performance by our outstanding undergraduate students.


First place, third year in a row

The results of the 2012 Iowa Collegiate Math Competition are out. 

Ruth Berger from Luther College, organizer of the competition, announced that the top-scoring team was "Iowa City West Varsity Team 1" from Iowa State University with 98 points out of 100.  A close second was "What's Your Problem?" , a combined Drake/Drake/Wartburg team (95 points).  There was a 3-way tie for 3rd place, each team with 94 points, between: "Lemma Llama" from Cornell, "Score" from ISU, and "Lemma Lemur" from Cornell.  

The coveted trophy will therefore return to ISU for another year, to be placed in the Mathematics Department office in 396 Carver. 

Each team consisted of three students, who had 3 hours to work 10 problems.  The first place team "Iowa City West Varsity Team 1" from ISU consisted of Nathan Rehfuss, Kevin Moss, and Tyler Chenhall.  The third place team " Score " from ISU consisted of Matt Krambeer, Hao Yuan, and Benjamin Sheller.  In 9th place with 84 points was ISU team "Gamblers" consisting of Chunlei Yuan, Xiaosheng Zhan, and Shenzhi Wang.

Both Nathan Rehfuss and Kevin Moss were also on the first place teams one year ago and two years ago.   They graduate this semester.
The 18th annual Iowa Collegiate Mathematics Competition took place on Saturday, February 25, 2012, at the University of Iowa.  Thirty-eight teams participated this year, from thirteen different colleges or universities. ISU had six teams, plus one student on a team with students from the University of Northern Iowa. 

Participants from ISU were:  Tyler J Chenhall, Michael Doody, Yanbin Fu, Matt Krambeer,  Xinu Ma, Xuetong Mao, Hannah K McCuddin, Kevin Moss, Wu Qianrong, Nathan Rehfuss, Ke Ren, Benjamin A Sheller, Xiyuan Sun, Diego H Useche-Reyes, Shenzhi Wang, Chunlei Yuan, Hao Yuan, Ruisi Zhang, and Xiaosheng Zhang.

The local organizer and coach from ISU was Professor Stephen Willson.

Congratulations to all the participants, and especially to first place winners Nathan Rehfuss, Kevin Moss, and Tyler Chenhall. 


Ling Long wins Ruth I. Michler Memorial Prize

The Association for Women in Mathematics (AWM) and Cornell University are pleased to announce that Ling Long, Iowa State University, will receive the 2012-13 Ruth I. Michler Memorial Prize.

The Michler Prize grants a mid-career woman in academia a residential fellowship in the Cornell University mathematics department without teaching obligations. This pioneering venture was established through a very generous donation from the Michler family and the efforts of many people at AWM and Cornell.

Ling Long was selected to receive the Michler Prize because of her wide range of mathematical talents. In 1997 she earned a B.Sc. from Tsinghua University, Beijing, China, majoring in mathematics with a minor in computer science and engineering. Long received her Ph.D. in mathematics from the Pennsylvania State University (PSU) in 2002. She studied modularity of elliptic surfaces under the direction of Wen-Ching Winnie Li from PSU and Noriko Yui from Queen’s University.
Before coming to the Iowa State University in 2003, where she is currently an Associate Professor in the Department of Mathematics, Long spent a year as a postdoctoral fellow at the Institute for Advanced Studies.

Long’s research involves modular forms for finite index subgroups of the modular group. These groups play an important role in Grothendieck’s program of dessins d’enfants (children’s drawings. Her work is partially funded by the National Science Foundation

At Cornell, Long plans to work with Ravi Ramakishna on Galois representations attached to noncongruence modular forms based on the pioneering work of Anthony Scholl and her joint work with Oliver Atkin, Winnie Li, and Tong Liu. The Langlands philosophy predicts that the L-functions of these Galois representations should be expressible in terms of L-functions of automorphic forms. Such a connection has far-reaching impacts on the arithmetic of modular forms. Long also looks forward to potential collaborations with other faculty members at Cornell.

Great Plains Math League competition held at ISU

On Saturday, February 11, the Iowa State University hosted a round of the Great Plains Math League competition.  We hosted 181 students from 20 schools.  The teams were accompanied by a total of 30 coaches.  25 faculty, graduate, and undergraduate students worked as volunteers to help the day run smoothly.

Bergman's new Algebra textbook review on MAA site

Michael Berg, professor of mathematics at Loyola Marymount University in Los Angeles, reviews Cliff Bergman's new book, Universal Algebra: Fundamentals and Selected Topics.

Graduate student Orizaga published

In his 4th semester at Iowa State, graduate student Saulo Orizaga has been published in the Journal of Theoretical and Applied Mechanics 50, 1, pp. 301-319, Warsaw 2012. While working on his demanding program at Iowa State, Orizaga continued working with UTPA mentor Daniel N. Riahi to finalize the text of On combined spatial and temporal instabilities of electrically driven jets with constant or variable applied field. The paper, which contained the higher level of computations, had systems of ODEs that were obtained from PDEs and explored certain modeling assumptions that they were able to carry on with the use of Newton's method for 2 variables. The case on non-linear effects was not considered in the process, but mentioned as a possible factor to be considered for future models.


Matzavinos presents colloquium at Ohio State's MBI

After being recognized by an Early Career Award from the Mathematical Biosciences Institute at Ohio State, Anastasios Matzavinos spent Fall semester at MBI. A video of the colloquium he gave there on November 28 can be viewed here.


Kliemann invited keynote at XV Bolivian Congress of Mathematics

Planners for the XV Bolivian Congress of Mathematics invited Wolfgang Kliemann to travel to Cochabamba, Bolivia November 19-27 to keynote the conference. Kliemann presented Continuity and persistence in dynamical systems.


Schultz article on challenging secondary students appears in NAGC newletter

Authored by Chris Schultz, Secondary students need to be challenged and supported in the STEM areas appears on pages 3-6 of the October 2011 Stem and Leaf newsletter published by the National Association for Gifted Children.


Graduate students present posters at the Fall 2011 AMS Central Section Meeting

Paul Hertz
An Application of Sharply Transitive Group Actions to Music

Music theorists model pitch-classes by elements of Z_12. In twelve-tone serialism, music is constructed from sequences of 12 distinct pitch-classes, called tone rows. The melodic and harmonic content of a twelve-tone work is drawn from the orbit of a tone row under the action of the semidirect product Z_12 \rtimes (Z_2 \times Z_2) on the direct product (Z_12)^12. We generalize to the action of the semidirect product G \times (Z_2 \times Z_2) on X^|G|, where G acts regularly on X, give a musical example involving the sharply 2-transitive action of AGL(7), and discuss related work.

Cory Howk
Computational Exploration of a Single-Cell Based Model for Uterine Epithelial Cancer

The most common locus for oncogensis are the epithelial tissues, highly proliferative regions that are subjected to harsh environments. Prominent among these is the uterine epithelium. Our single-cell based model of cell proliferation has shown the ability to simulate many varied cancer phenotypes. We examine the effects of variation in parameters on the probability of transformation through maximum likelihood estimation and weighted nonlinear least squares analysis. Comparison with epidemiological data yields both biological insight and methods to calculate phenomenological parameters.

Dominic Kramer
Identifying a Basis in a Frame

Given a frame, we present a convex optimization problem which identifies a subset of the frame which is a basis with some nice properties. This is joint work with Eric Weber and Mark Lammers.

Michelle A. Lastrina
Sum-list-coloring and sc-greedy graphs

Let G=(V,E) be a graph and f be a function assigning list sizes to the vertices of G. The graph G is f-choosable if every assignment of lists of colors to the vertices of G, where the list sizes agree with f, has a proper list-coloring of G. The sum choice number is the minimum of the sum of list sizes for f over all choosable functions f for G. The sum choice number of G is at most |V|+|E|. When the sum choice number of G is equal to this upper bound, G is said to be sc-greedy. This poster will illustrate some results on the sum choice number and give examples of sc-greedy graphs.

Tracy McKay
The Edit Distance Function for Graphs

Define the edit distance between two graphs on the same labeled vertex set to be the symmetric difference of their edge sets. The normalized edit distance from a graph G with n vertices to a hereditary graph property H is the minimum edit distance from G to any graph in the property divided by n(n-1)/2.

The edit distance function for H is a function of p and plots the limit as n goes to infinity of the maximum value of the normalized edit distance over graphs with edge density p. This poster explores the theory behind the edit distance function and results for some hereditary properties.

Steven Osborne and Nathan Warnberg
Computing Positive Semidefinite Minimum Rank for Small Graphs

The direct computation of positive semidefinite minimum rank of a graph G is difficult.
However, there are a number of known bounding parameters and techniques which can be calculated and performed on a computer. We programmed an implementation of these bounds and techniques in the opensource mathematical software Sage. The program, in conjunction with the orthogonal representation method, establishes the positive semidefinite minimum rank for all graphs of order 7 or less.

Jun-Koo Park
A non-homogeneous Gaussian Network Model for Protein Residue-level Fluctuations

To study the dynamic properties of biological molecules using computational techniques, several approaches can be considered. One of them is Normal Mode Analysis. In NMA, a complete analytical solution of the equation of motion can be obtained. Another approach is Gaussian Network Model. In GNM, a large biological molecule can be modeled as an elastic network composed of nodes and springs. We propose a new method called the non-homogeneous GNM to obtain a finer-grained GNM with non-homogeneous contact constants. In this method, we define the contact matrix using the Hessian matrix.

Arianne Ross
Positive Semidefinite Zero Forcing

The positive semidefinite zero forcing number Z+(G) of a graph G was introduced by
Barioli et. al.. We establish a variety of properties of Z+(G): Any vertex of G can be in a minimum positive
semidefinite zero forcing set (this is not true for standard zero forcing). The effect of various graph operations on positive semidefinite zero forcing number and connections with other graph parameters are studied.

Zachary D. Voller
An Optimal Solution to the Generalized Distance Geometry Problem

NMR experiments on a protein yield a set of inter-atomic distance ranges. A number of structures satisfying the distance constraints, derived from distance range and bond information, are then generated. This ensemble of structures is often under represented, and it generally does not accurately represent the fluctuations within the proteinÃs structure. In this poster we present an alternative problem in which it solution, derived from interior point optimization, provide a single representation for both a protein's conformation and the ensemble of possible structures.






Tribute to Lawrence E. Payne

written by Howard A. Levine

Lawrence E. Payne, who received his BS in Mechanical Engineering in 1946 and an MS and PhD in Applied Mathematics from Iowa State in 1950 under D. L. Holl, died August 11, 2011 of acute lymphoma. He was born in McCleansboro, Illinois, a small farming community near Carbondale in 1923. His first position was at the University of Arizona, followed by 14 years at the University of Maryland in the Institute  for Fluid Dynamics and Applied Mathematics. He joined the faculty of Cornell University as a full professor in 1965. Although he had a very distinguished academic career, he was fond of telling me that his first employer was the Merit Shoe Company in Detroit where he was first employed in July 1941, as a shoe salesman.  In his usual self-effacing style, he neglected to mention that by the time he left the shoe business in February 1943 to join the U. S. Navy, he was the assistant manager. He served a little  over three years in the Navy.

Larry, as he preferred to be called, was a recognized international leader in partial differential equations, especially in isoperimetric inequalities and improperly posed problems of mathematical physics. (Improperly posed problems are those for which the solution either fails to exist, fails to be unique when it does exist, or fails to depend continuously on the data.) He authored or coauthored nearly 300 articles and two books. He held visiting research positions for extended periods at the University of Genoa, the University of Florence, the University of Berlin, the University of Dublin, the University of Glasgow, Heriot Watt  University, the University  of Virginia  and the Swiss Federal Technical University  (ETH)  in Zurich.   He was the major professor for 15 PhD students, some of whom came from diverse backgrounds and from all over the world, including Iran, South Africa and South Korea.

He was primarily responsible for rebuilding applied mathematics and for the establishment of the Center for Applied Mathematics at Cornell. His quiet, persuasive manner enabled him to succeed where individuals with more dynamic but less politic personalities had failed.  This center as well as the group in numerical analysis and partial differential equations is considered to be among the best in the world.

Among his awards was the prestigious Steele Prize from the American Mathematical Society given infrequently for an expository paper (Isoperimetric Inequalities and Their Applications, (Soc. Ind. Appl . Math. Rev. 9 (1967) 453-488) that has made a significant and lasting impact on the field in which it is written. In 1990 he received an honorary Doctor of Science degree from the National University of Ireland. In 1992 he received the Citation of Merit from the College Liberal Arts and Sciences at Iowa State.  A three day conference in his honor was held at Cornell in October, 1990 that was well attended by friends and colleagues from all over the world.

Larry never forgot his Iowa State connections.  He always spoke appreciatively and highly of the education he received here. He returned to Ames many times over the years to attend class reunions or to reconnect with old friends and colleagues.  It was here that Larry met his lovely wife, Ruth Winterstein Payne, who was also an Iowa State alumna. They are survived by four of their children, Chris, Marcia, Michelle and Steven, as well as several grandchildren.

In addition to his numerous scientific achievements, his colleagues the world over held him in the highest esteem as a friend, advisor and and colleague. One of his former students remarked that he ”never heard an unkind word about Larry’s work or about him personally.” A colleague at Cornell commented that ”When they made Larry, they threw away the mold.” As for me, outside of my own family members, he was probably the best friend I ever had. This is, without a doubt, a sentiment with which many will agree.


Campus United Way campaign underway

  • The official campaign end date this year is October 29. Please return envelopes by Friday, October 29.
  • The 2011 goal for the College of Liberal Arts and Sciences is $35,500.
  • Faculty, staff and students are encouraged to place their return envelopes directly in campus mail. Envelopes will go to a campus lock box rented by Story County United Way and will be picked up by staff from the Story County United Way office.
  • Social security numbers are not to be used on the pledge cards. An envelope is provided for returning pledge cards (which should be signed and have the university id number listed).
  • Information about the campaign can be found on the ISU United Way website:
  • University-wide incentives:
    • Each donor will receive a coupon for four free tickets to the ISU / Iowa women’s basketball game on December 7, 2011.
    • Each donor will receive an Iowa State University pin.

Once again, thank you for your help to make this a successful campaign!


Graduate students Zach Voller and Junkoo Park attended a week long workshop on Discrete Geometry and Optimization last week at the Fields Institute for Research in Mathematical Sciences at Toronto, Canada. Voller presented a research poster entitled An Optimal Solution to the Generalized Distance Geometry Problem for Protein Structural Determination. Park presented one entitled A Non-Homogeneous GNM Model for Protein Residue Level Fluctuations. Both posters were well received by the participants of the workshop.



Career Day 2011 lineup

L-R: Wolfgang Kliemann, Dale Zimmerman, Jeff Anderson, Cliff Bergman, Leslie Hogben, Andrei Lyashenko, Cynthia Clark, Elgin Johnston, Alicia Carriquiry.


Distinguished alumni lineup to highlight career opportunities

Several distinguished Iowa State alumni will return to campus on September 23-24 to showcase career opportunities for students of mathematics and statistics. 

Cynthia Clark, Administrator (Director) of USDA’s National Agricultural Statistics Service (NASS), oversees USDA’s efforts to collect and disseminate data on every facet of U.S. agriculture.  Clark is an accomplished statistician who is highly respected for her expertise in survey research and development. Before joining NASS, she directed statistical research and survey methodology for the United Kingdom’s Office for National Statistics and, prior to that, at the U.S. Census Bureau.  Clark received MS and PhD degrees in statistics from Iowa State.

Andrei Lyashenko is head of Quantitative Research at Quantitative Risk Management (QRM), one of the world's leading enterprise risk management consulting firms. His expertise is in mathematical finance, interest rate modeling, risk management, quantitative methods for pricing and hedging of financial products. Lyashenko was a member of the Department of Mathematics at Iowa State in the 1990s.

Dale Zimmerman is the Robert V. Hogg Professor of Statistics in the Department of Statistics and Actuarial Science at the University of Iowa. He is also part of the Interdisciplinary Graduate Program in Informatics, and of the Computational Epidemiology Group. His interests are in spatial statistics, linear models, experimental design, multivariate analysis, and environmetrics.  Zimmerman received a PhD in statistics from Iowa State.

Jeff Anderson is the Dean of the College of Science, Technology, Engineering and Mathematics at the University of Wisconsin- Stout. His interest is in applied partial differential equations and his current projects include models of large river food webs and tumor-induced angiogenesis.  Anderson has a PhD in applied mathematics from Iowa State.

Paul Hertzel is a member of the mathematics faculty at North Iowa Area Community College. He has an MS degree in mathematics from Iowa State.

On Saturday, September 24, 2011 these five alumni will talk to graduate students in mathematics and in statistics about career opportunities in academic research institutions, in government and non-governmental organizations, in industry, and in four and two-year colleges. Together with faculty members from both departments they will analyze recent employment trends and give advice on how to be competitive in a tight labor market. The event starts at 9:00 am in 305 Carver Hall, with coffee and pastries being served at 8:30 in 400 Carver.

On Friday, September 23, 2011 Drs. Clark and Lyashenko will visit with undergraduate students about careers in mathematics and statistics in industry and government. This event will start at 4:00 pm in the Sprague Mathematics Resource Room, 400 Carver Hall.


Cynthia Clark

NASS administrator and ISU alum on campus September 23-24

Dr. Cynthia Clark, Administrator of USDA’s National Agricultural Statistics Service (NASS), overseeing the agency’s efforts to collect and disseminate data on every facet of U.S. agriculture, will visit campus later this month to talk with students about job opportunities with the Federal Government. Clark will also spend time with faculty members.

Clark is an accomplished statistician who is highly respected both in the United States and overseas for her expertise in survey research and development. Before joining NASS, she directed statistical research and survey methodology for the United Kingdom’s Office for National Statistics and, prior to that, at the U.S. Census Bureau.

Clark has strong roots in agricultural statistics, having previously spent 13 years working on the Census of Agriculture and serving as the Director of the NASS Census and Survey Division. She has also served in numerous professional positions with the American Statistical Association (ASA), the International Statistical Institute (ISI) and the International Association of Survey Statisticians. Additionally, she is a fellow of the ASA, an elected member of ISI and a Fellow of the Royal Statistical Society.

Under Clark’s leadership, NASS conducts hundreds of surveys and issues nearly 500 national reports each year on agricultural production, economics, demographics, and environmental statistics. NASS also conducts the Census of Agriculture every five years, providing the only source of uniform, comprehensive agricultural data for every county in the nation

Postdoctoral position in Control of Quantum Systems

ISU-PDQS [#3017]

A postdoctoral position is available in the area of Control of Quantum Systems at the Department of Mathematics of Iowa State University starting January 2, 2012. The position is for a period from a minimum of one year to a maximum of five years. The supervisor for the project will be Professor Domenico D'Alessandro.  The successful candidate is expected to conduct research in the area of quantum control and to teach up to one course per semester. Given the
interdisciplinary nature of the project, candidates with expertise in different fields of mathematics and physics are encouraged to apply. These include, but are not limited to: Geometric control, Lie groups and Lie algebras, Infinite dimensional control systems, stochastic systems, quantum field theory, quantum mechanics and quantum information.

The project is  part of a multi-university initiative involving Iowa State University, University of Southern California, University of Massachusetts Boston, University of California at Riverside, Princeton University and Griffith University (Australia). This project covers aspects of quantum control from theoretical to experimental. The successful candidate is, therefore, expected to interact with an interdisciplinary team and participate in conferences and meetings with other participants in the project.

If interested, please apply at and include the following information

  • Curriculum Vitae
  • Document describing scientific achievements and interests
  • Teaching Philosophy
  • 3 letters of recommendation (2 to address research, 1 to address teaching)

Direct information to
Professor Domenico D'Alessandro
Department of Mathematics
Iowa State University
440 Carver Hall
Ames IA 50011,

Willson organizing vans to AMS meeting in Lincoln

The AMS Central Section meeting this fall is October 14-16 at Lincoln, Nebraska.  The program for the meeting is online. Those interested in vans contact Stephen Willson at