NSF Head Presents With Penn State Researchers
Dr. Subra Suresh, with the support of three renowned Penn State researchers, headlined the Nelson W. Taylor Lecture in Materials on Thusday. This year’s theme was Materials Frontiers, where it was clear that the future of research lies in the ongoing collaboration between scientists of different specializations.
Department Head Gary Messing opened by thanking Suresh, Director of the National Science Foundation. The NSF is an independent, publicly funded organization, dedicated in part to advancing all fields of science and engineering. Basically, this organization is charged with making sure the United States stays respectable in the world of academia. After a brief history of the Taylor Lecture Series, Messing invited to the stage Dr. Moses Chan.
Chan opened by personally thanking Suresh and the NSF, as his work would not be possible without their funding. Chan’s lecture, Can a Solid be a Superfluid?, covered an experiment he conducted with the help of a graduate student where he found that Helium-4, a solid, had some very peculiar test results. “We performed the experiment in 2001, performed control experiments for three years, and published in 2004,” Chan remarked, noting the careful process researchers must go through for their work to be deemed credible.
In classical mechanics, inertia is the tendency of an object to want to stay put. His experimental results, since confirmed in over 10 labs worldwide, showed inertia readings were smaller than they should have been at very high speeds (thousands of rotations per second). That means that Helium-4, or at least a portion of it, wasn’t showing as much resistance to the spin as it should have. This could be explained by a leak in helium, but upon heating up (note: experiments are carried out at a temperature near Absolute Zero, as that is the only way helium can exist as a solid), the readings were normal.
So with a leak dismissed, another possibility was that a percentage of the solid, estimated to be less than 1%, was actually adopting the properties of a superfluid, which implies those molecules were showing no resistance to spin because they have zero viscosity. In other words, they don’t resist anything, at all. He devised a creative next step. Under the same conditions but with a bit of magnesium to block the helium in the cylinder from making a complete circle, it was shown that the rotational inertia was consistent with a more classical approach. “Back in the 60s, scientists were hedging their bets,” he jokes, “they said [a solid as a superfluid] was ‘not impossible’”.
Chan ended the speech by again acknowledging the NSF. Included on the last slide were some stats: 20 Ph.D.’s, 8 M.S.’s, ~30 undergrads, and 15 post-doctorates. These are the researchers whose work is made possible by the contributions of the National Science Foundation.
Next to speak was award-winning researcher Tony Huang, Ph.D., who also benefits from NSF funding. With a comfortable stage presence, Huang began with a story about his time in college, where he was a big soccer fan. His favorite player was Roberto Carlos of Brazil, for his ability to make the ball curve on a seemingly impossible path on the way to the goal. Juxtaposed was a video captured using a powerful microscope, in which a grad student was able to recreate the same exact scenario as the famous goal, using individual particles manipulated through acoustofluidics. “It is a fantastic way to burn professors’ money, but it is not particularly useful”, he quipped with a smile.
“Acoustofluidics,” Huang continued, “is the combination of acoustics and microfluidics.” Previously, the only way to manipulate single particles was through the use of a laser, known as optical tweezers. The downside of this technique is that when used on organic cells, they tend to die not soon after. Also, the energy expended is enormous. What Huang and his colleagues were able to do is nothing short of revolutionary.
Through the use of sound waves, they were able to duplicate the same end result as optical tweezers, single particle manipulation. What is so revolutionary is that this technique is incredibly non invasive, with over 99% of organisms surviving a ten-minute exposure, very close to the un-exposed result. Equally important is the fact that it uses 10 MILLION times less power than optical tweezers. He ended with a fun video in which one of his students made a particle spell out PSU.
The last member of the Penn State faculty to present was Michael Hickner, on the topic of Ion and Water Motion in Self-Assembled Polymers. “The working theory is that ions (charged particles) move through small channels in polymers,” Hickner began. “We can manipulate these channels, and the subsequent flow”. In many ways the human epidermis mirrors a polymer in that it too has channels, but we call these pores. One of the goals of his research is to use “electrical current to push [charged] drug molecules through skin and into the blood stream,” which would be an incredibly quick and efficient method of delivery.
Suresh, the keynote speaker, gave the final presentation of the morning. Relieved to be able to give a talk about science, as opposed to the agency he heads, he spoke about Biomechanics and Human Disease. The disease he and his colleagues were working on understanding better is one responsible for over a million deaths per year, making it more lethal than AIDS. Malaria is transmitted by mosquitoes, and causes fevers, which is the extent of common knowledge on the subject. He went on to demonstrate just how nasty of a parasite it really is.
The brain needs oxygen to function. It gets this oxygen from red blood cells, the size of which “from birds to elephants, doesn’t change much”. In order to get to the brain, red blood cells have to pass through very tiny openings, which are a fraction of the size of the cells themselves. Healthy red blood cells are very flexible, and can stretch themselves to pass through without a problem. Cells infected with the malaria parasite become incredibly stiff within 48 hours, which consequently can clog up these passageways. Normal cells can still pass through, but as he showed (through comparable lab conditions) experimentally, their progress becomes greatly hindered, and it takes longer. To put it in perspective, the average life cycle of a red blood cell is 120 days. That means it will have to pass through that inhibited opening millions of times.
Malaria comes from mosquitoes. These pregnant females need protein for their eggs, which they get from human blood. Transmitted in the process are parasitic spores, which grow over time. These spores effectively ‘fill up’ the red blood cell, which stiffens and becomes sticky as a result. How this happens is not fully understood. One parasite can breed 32, and after a period (usually 48 hours), the cell is so full that it explodes, releasing the parasites to repeat the process and causing the host to spike a fever in the process. In countries where malaria is most prevalent, it is almost impossible for the average victim to even diagnose what kind of illness they have.
Suresh sees the development of technologies made possible in part by the work of Huang as a stepping stone to his “holy grail:” portable, disposable chips costing 10 cents, capable of revealing a) whether the person has malaria, b) what kind of malaria it is (there are several) and c) if the malaria is the cause of the fever. Experiments performed as recently as last year showed the plausibility of such a vision. “The experiment was designed in Massachusettes, fabricated in Taiwan, and performed in Singapore by an MIT student” noted Suresh with a proud smile.
Suresh showed using advanced computer modeling that nature chose that particular shape for red blood cells because of its energy efficiency. In the process of studying, he also managed to discover a completely new method to diagnose if a cell has cancer, for much cheaper. As opposed to present methods, which is blood testing to look for markers consistent with cancer, Suresh was able to use a biomechanical approach to determine on an individual cell basis. In a test of fourteen cells, seven clean and seven infected, an independent researcher was able to correctly predict all seven cancerous cells using this method, which (very simply) consists of shooting a ray at a lever positioned above a cancer cell, then probing how the cell responds.
To conclude, Suresh restated his goals of finding a fundamental cellular understanding, improving diagnostic capabilities for diseases, novel therapeutics, and increasing drug effectiveness. This is made possible by the continuing collaboration of scientists worldwide, including those in the fields of engineering, materials, chemistry, physics, biology, and medicine. Science of tomorrow promises to blur the line between these fields, once considered worlds apart, as they become more intertwined.
Whether it is to discover the fundamental laws governing the universe, create new technology, improve water treatment, or fight disease, the scientists of today have one common goal: make the world of tomorrow a better and more knowledgeable place. It is comforting to know that for every Sandusky in the world, there is a Suresh. For better or worse, we are all, unmistakably, connected. Spread the love, people.