Leave your heart in San Francisco. And while you're at it, leave your ears in Boston, your liver in Tennessee, and your lungs in Seattle.

Charles DeLisi, who began the Human Genome Project, is trying to get financial support for an even more awesome undertaking: re-creating in software all the physiological processes of a human being. DeLisi, a professor and director of bioinformatics at Boston University, hopes to create a virtual human whose organs will be dispersed among research facilities across the country.

This is no cyborg. It would be a distributed computer program that uses algorithms to re-create the functions of the human body, and in particular to study how functions in one part of the body impact others. Ultimately, the models could predict what a chemical, virus, bacterium, or physical trauma would do at the cellular, organ, system, and organism levels. Doctors in an emergency room could see the effects of physical trauma without opening up the body, and patients could have drugs customized to their body chemistry.

In a setup similar to that of the Human Genome Project, the Virtual Human Project would divvy up computational responsibilities. Specialists at each university or laboratory would develop software that represents a particular organ and then test what effect different stimuli have on that organ.

Software for some organs and functions would be completed far in advance of others. Development would be ongoing, and there wouldn't be a completed virtual human, but rather an ever-evolving model. That, combined with the complexity of the programming, dictates that the virtual human must be developed and run on a distributed basis, DeLisi says. Boston University has already created a virtual cochlea, the bones inside the ear that vibrate in response to sound waves and translate them into electrical impulses for the brain. And, DeLisi says, scientists and programmers will make major progress in the next year on mapping how our sense of smell works and re-creating that in software. Vision is expected to follow over the next ten years or so.

PHYSICAL LIMITATIONS

The virtual human would link the organ models over the Internet as they are created and eventually produce a holistic picture of the human organism. "It's been done in astronomy. It's been done in molecular biology. It's not been done in physiology," DeLisi says.

Researchers say biological information about humans has become too specialized, voluminous, and dispersed to manage effectively without analytical and interactive help from computers. "The human has got a wonderfully adaptable brain, but the input is slow, and we get distracted," says Clay Easterly, a researcher at Oak Ridge National Laboratory in Oak Ridge, Tennessee, who is also promoting the virtual human. "I don't see any way for a human being, or a group of human beings, to synthesize this vast data."

While the project has drawn some interest from the government, academia, and industry, for the time being, the virtual human is likely to grow from relatively small efforts, such as the virtual cochlea project. But there are other issues as well. Computer models are still relatively crude, and they're narrowly defined to a particular reactionÑin a cell or in an organ, for example.

The many-to-many structure of the Internet and the use of XML would be the framework for sharing information that now exists in isolation, DeLisi says. But creating programs that accept input from other applications is a challenge. The virtual human would require integrating processes and software across vastly different scales, from molecules to whole organisms. "I don't think we have the foggiest notion of how to go about it," Easterly says. Programming would have to be done at each level--the molecular, cellular, organ, and systemic--simultaneously and progress up and down until the functions met. Biological research would influence, and be influenced by, the programming effort. The entire process could take a hundred years or more, especially since it must ultimately include the brain. "That, I think, is a ways off," DeLisi says.

-Jennifer DiSabatino. Reprinted with the permission of ComputerWorld magazine.

Light, in the form of lasers, has for some time been a frequent scalpel of choice for surgeons infields such as ophthalmology and dermatology. New research by Irving Bigio, an ENG biomedical engineering professor, and colleagues at University College, London, may pave the way for replacing the scalpel with light when performing biopsies to identify whether cells are cancerous.

The new technology, recently tested for the optical detection of breast cancer, uses two thin optical fibers. One carries light to the surface of the tissue where cancer is suspected. Light scattered back from the tissue is relayed by the second fiber to a spectrometer, where intensities at different wavelengths are recorded and analyzed on a portable computer. The analysis compares the optical signature of the tissue being tested with known signatures of healthy and cancerous tissue.

The researchers identified a range of healthy and cancerous signatures over four years by taking optical measurements on over 200 consenting patients and comparing the results with conventional biopsies. The computer "learned" to identify cancer signatures from a random sample of the biopsies. The other biopsies were used to test the technique. The same diagnosis resulted 93 percent of the time for breast tissue, and 85 percent of the time for lymph nodes.

Unlike conventional biopsies, which can require up to several days for samples to be examined in the lab, optical biopsies take only a fraction of a second. They can be done right in the operating room, allowing surgeons to make immediate clinical decisions about whether the margins around the site of the tumor are clean or whether further surgery is needed.

The researchers caution that the results are only preliminary, and large-scale tests on many patients will be required before this technology can be adopted. They are also investigating possible uses of the technology for diagnosing cancers in other parts of the body, like prostate cancer. -Joan Schwartz

Element number 73, tantalum, was named after the mythological king of Lydia, whose punishment by the gods was being surrounded with food and drink placed just beyond his reach. Tantalum, too, has proved a challenge--it is an extremely strong and versatile metal, but it is difficult to synthesize and purify. Uday Pal, an ENG professor, and colleagues in the ENG department of manufacturing engineering have achieved a major breakthrough in producing tantalum.

The team, including research associate Christopher P. Manning and graduate students Ajay Krishnan (ENG '04) and Timothy Keenan (ENG '02), has successfully produced tantalum using a "green" and highly efficient new process known as solid oxide oxygen ion conducting membrane process (SOM). It uses an electric potential applied across a solid oxygen-ion-conducting membrane to selectively separate oxygen from metal oxide (dissolved in a solvent) and produce the purified metal.

Tantalum has numerous applications. Drawn into a fine wire, it can be used to evaporate many other metals. Incorporated into glass, it increases the index of refraction, producing high-quality camera lenses. Because it is nearly impervious to chemicals at room temperature and does not react with bodily fluids or irritate the body, tantalum is ideal for surgical equipment, sutures, and implants such as artificial joints.

It is also used in components for chemical plants, nuclear power plants, airplanes, and missiles. Electronic capacitors made of tantalum are used in such diverse applications as hearing aids, pacemakers, ignition and motor control systems, airbag protection systems, cell phones, laptops, and digital cameras. A composite of tantalum carbide and graphite produces one of the hardest materials known.

Pal and his collaborators have also used the SOM process to successfully synthesize magnesium. The process can be used as well to synthesize metals such as titanium and aluminum. For all of these methods, the SOM process has the potential to be more energy-efficient, cost-effective, and environmentally sound than conventional methods. Pal and Steven Britten, a former student and research associate at BU, will receive the 2003 Extraction and Processing Technology Award from the Minerals, Metals and Materials Society for a paper related to the SOM process. -Joan Schwartz