January 2000

News about Science, Technology and Engineering at Iowa State University

Power-packed equations
Do powerful mathematical equations using control theory carry the punch to combat diseases? Mustafa Khammash thinks so and may have delivered the first blow by developing a mathematical model that helps unravel the mystery of milk fever in dairy cows. During calving, the regulatory system of these animals fails to cope with large calcium demands, resulting in sickness and, if not treated, death.

Khammash, an Iowa State University associate professor of electrical and computer engineering, is working with graduate student Hana El-Samad and Jesse Goff, a research scientist at the National Animal Disease Center in Ames. "We are applying ideas from control theory and engineering to the biological areas," says Khammash, who envisions powerful control theory equations targeting human diseases in the future.

Khammash's model accurately describes the plasma calcium profiles seen in real physiological data obtained from dairy cows. It explains how the body actually does the control and how the different hormones interact to maintain equilibrium.

"Using this simulation, we can see what factors contribute to milk fever and what factors help alleviate it," Khammash says. "For example, we are able to predict that animals given small quantities of a certain hormone prior to calving will be less likely to develop milk fever and their calcium regulation mechanism is able to adjust to the increased demand. This has been confirmed by physiologists in the field."

Goff adds: "I think the future utility of the modeling concept is to examine control systems in the body and predict 'undiscovered' hormones or nervous input that act as a control for various physiological parameters, such as blood pressure, blood glucose and other complex systems." For more information, contact Khammash at (515) 294-9950, or Sunanda Vittal, Engineering Communications, (515) 294-8787.

Shedding new light on advanced materials
A compact furnace combined with high-energy x-rays is enabling researchers at the U.S. Department of Energy's Ames Laboratory at Iowa State to directly record the chemical and structural changes of complex materials under real processing conditions. This information, which is crucial to understanding and controlling the composition and microstructure of new materials, previously took months or years to collect. The researchers who designed the furnace now can gather data in a few days while getting a more detailed picture of the changes in a material's crystal structure as it heats and cools. "We're seeing details of the phase transitions that I don't think anybody has ever described before," says Ames Lab scientist Matt Kramer.

The new furnace is a scaled-down version of a standard laboratory tube furnace, measuring about 18 inches (46 cm) tall and 6 inches (15 cm) in diameter. It allows x-ray diffraction measurements to be performed at temperatures up to 1500 C (2730 F) under flexible environments, duplicating the conditions used in materials processing. The reactions are monitored with a time resolution of less than two seconds, fast enough to make a virtual movie of the material's structural transformation during temperature-driven processing.

Kramer said the new system is providing highly precise information about complex materials such as structural ceramics, superconducting wires and nanostructured materials. For more information, contact Kramer at (515) 294-0276, or Susan Dieterle, Ames Lab Public Affairs, (515) 294-1405.

Nondestructive evaluation helps build bridges
Iowa State University's Center for Nondestructive Evaluation (CNDE) is improving the caliber of the nation's quality and safety inspectors through improvements in educational materials. Nondestructive evaluation methods are used to inspect the internal integrity of a part or material without destroying it. They are used widely in several industries, most notably the airplane industry.

In an effort to upgrade NDE inspection technician education programs, the North Central Collaboration for Education in Nondestructive Evaluation links CNDE and ISU's College of Engineering with four Midwestern community colleges. The program's offerings to community colleges include interactive, computer-based educational materials; summer internships; and scholarships for students and professional development programs for instructors. ISU faculty co-host NDE Engineering Information Days with CNDE researchers, and the College of Engineering has worked with CNDE to establish routes for community college NDE students to transfer to ISU. The collaboration has also produced Internet-based materials aimed at junior and senior high school students to introduce NDE as a career choice and to encourage the study of math and science as preparation for technical careers.

For more information, contact Brian Larson, Iowa Demonstration Laboratory for NDE Applications, (515) 294-8158, or Danelle Baker-Miller, IPRT Public Affairs, (515) 294-5635.

- 30 -
Iowa State homepage

University Relations, online@iastate.edu
Copyright © 1999, Iowa State University, all rights reserved