Authors Posts by Daniel Dunaief

Daniel Dunaief

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Some people like slamming things together, whether it’s a young child sitting on a floor crashing two matchbox cars into each other or an adult behind the wheel of a bumper car at a fairground.

Gene Van Buren gets to do the same thing, although he’s not using cars. He’s propelling a gold nucleus along a 2.4-mile track at speeds approaching that of light and slamming it into another gold nucleus.

The effects of the collision are more spectacular, albeit on a miniature scale, than watching the bumper pop off a matchbox car. The temperatures in these crashes climb to 4 trillion degrees Celsius. That’s 250,000 times hotter than the temperature in the center of the sun.

“The day when we get to see what [such a collision] looks like on a computer screen, we are all like a bunch of kids,” said Van Buren, an experimental nuclear physicist at Brookhaven National Lab. “It’s so cool. It’s what we’ve been working for for the past decade to do. We remember how exciting this is.”

Besides doing it because they can, nuclear physicists like Van Buren who work at the Relativistic Heavy Ion Collider (RHIC) study the results of those nuclear mash ups to gain a better understanding of the way nature works at very small scales.

When they’ve jammed these tiny particles together, they’ve been able to examine the way smaller ones, like quarks and gluons, interact. Quarks are the building blocks for protons (matter with a positive charge) and neutrons (those with a neutral charge). Gluons, which don’t have mass, serve as the “glue” that holds quarks together.

“From a theoretical calculation, we expected that once you got these gluons and quarks really hot, they wouldn’t want to interact with each other,” he said. Their collisions, however, showed the opposite, that these subatomic particles “still want to stick to each other.”

What that means is that the parts of the nucleus of an atom behave much more like a liquid than a gas. In a gas like air, Van Buren explained, molecules tend to flow freely away from each other. Liquids like water, on the other hand, tend to bind together. That is why water forms droplets when it is spilled.

“For us, this is very exciting because it has implications for the nature” of how these particles behave, “under normal, everyday conditions that we don’t necessarily observe from our perspective of everyday life,” Van Buren said.

At the same time, these experiments may simulate the kinds of conditions that existed during the beginning of the universe, at least according to the big bang theory. At RHIC, colliding these nuclei at such high speeds is similar to making a “little bang.”

The biggest difference, however, is that RHIC doesn’t collide matter with as much “stuff.”
“In the big bang, the universe started out dense and hot with a lot of material and energy. In our case, we have two out of those three” conditions, Van Buren said. “We have the density and heat.”

Still, by examining high temperatures and density, the scientists at RHIC may be able to see “how the universe evolved during that particular epoch.”

Van Buren said down the road, maybe decades of even a hundred years from now, other scientists can use the knowledge he and others are generating at RHIC to engineer new products.

“It was like that with electricity,” he said. “The first people studying it had no idea how this would affect their everyday life. Over 100 years later, look what electricity does. We can learn to engineer things with the knowledge we gain about the universe.”
Physicists like Van Buren are inspired by the first dozen years that RHIC has been operating (its first experiment was in the summer of 2000).

The scientists “have the pioneering spirit of climbing to the top of Mount Everest,” offered Jim Thomas, a visiting physicist from Lawrence Berkeley Lab in California who has worked closely with Van Buren for several years.

In addition to designing collision experiments, Van Buren has helped create computer programs that analyze the results of the collisions.

Van Buren “understands a lot about computers and a ton about physics,” said Thomas. “He’s able to make the physics/ computer connection very nicely.”

If Van Buren ever needs to consult with a computer-programming expert, he doesn’t have to look far. His wife Marie Van Buren, whom he met when he was at graduate school at the Massachusetts Institute of Technology, is a computer programmer at BNL.

The couple met when they joined a volleyball league at MIT. Marie, who is around 5 feet tall, sometimes sets up her 5-foot-10-inch nuclear physicist husband to spike the ball when they are on the same team.

Sports have always been an important part of Van Buren’s life, whether it was soccer in high school, track and racquetball in college or volleyball and, in summer, ultimate frisbee.
Residents of Middle Island, the Van Burens have lived on Long Island since 1998, when Gene did his post-doctoral work for UCLA at Brookhaven National Lab.

As for his research, Van Buren said his primary goal is “pure research,” in which the end result is knowledge, not a product. The basic knowledge of nuclear physics may one day pave “the way for new developments that perhaps no one today can dream.”

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When their son Dylan was under a year old, Debbie and Ron Cuevas noticed he couldn’t support his head and had trouble rolling over. They brought him to a pediatrician, who diagnosed Dylan with spinal muscular atrophy.

The doctor said he likely had two years to live. Determined to make every day count, the Cuevas family of Rockville Centre has rallied around their son, who is now 8 and in third grade.

A genetic disease with varying severity that weakens muscles in the central nervous system, spinal muscular atrophy (or SMA) has no current cure. Some with the disease die because they can’t breathe or swallow. SMA is the leading genetic cause of death among infants and affects about 1 in 6,000 newborns.

Researchers, including Dr. Adrian Krainer at Cold Spring Harbor Laboratory, however, have been working to find a treatment. Krainer has unlocked a potential solution. His work with antisense oligonucleotides (or ASOs) has been impressive enough in the lab and on mice that California-based Isis Pharmaceuticals started using his treatment in the first phase of clinical trials in December. It’s too early to determine the effectiveness of this approach.

SMA is a genetic disorder and is caused by a defective SMN1 gene, which is on the fifth chromosome. That gene produces the survival of motor neuron protein. Without enough of that protein, the motor neurons in the spinal chord gradually die and the muscles they control cease to function.

The solution to this recessive genetic disease may be in the genes themselves. There is a backup gene, called SMN2, that produces the same protein. The problem in children with the disease is that the backup often doesn’t produce enough protein or the protein isn’t complete or breaks apart.

Krainer’s lab has aimed one of its efforts at improving the function of SMN2. The problem with SMN2 is in something called splicing, a process where important pieces of genetic information (exons) are linked together while white noise (introns) is spliced or cut away. The exons are like the proverbial wheat and the introns are the chaff.

As DNA and its cousin RNA go from the genetic blueprint stage to the protein-building stage, there are signposts along the way that indicate whether the next set of genetic instructions is an exon or an intron. A repressor sits on SMN2 at exon 7 that mistakenly sends the cell’s RNA machinery away. The repressor acts like a “Do Not Enter” sign, making it hard for the cell’s machinery to recognize an exon.

Krainer’s lab has created a synthetic molecule called antisense oligonucleotide that replaces that “Do Not Enter” sign and encourages the gene splicing tools to include the information from exon 7 when it builds the survival of motor neuron protein.

In the lab, ASO has done its job, making SMN2 act like its much more effective SMN1 cousin. When Krainer injected ASO into mice with severe SMA, he found that they not only lived longer, but they also were able to grow and develop the same way as mice without the genetic defect.

Krainer’s lab is “changing how the splicing machinery” works, he offered. “We took the repressor out of the picture.”

Krainer has been working on SMA for over a decade. The Uruguay-native who has been at Cold Spring Harbor Lab since 1986 is on the advisory board for two SMA foundations.

He said he quickly moved from understanding SMA as an abstract cell mechanism problem to the urgent need to “do something about it. When [a disease] affects children and very young infants in particular, it is something even more touching.”
Residents of Huntington Station, Krainer and his family have made the Cold Spring Harbor Lab a family affair over the years.

Krainer’s wife Denise Roberts (who met Adrian when they were Ph.D. students at Harvard in the 1980s) is the deputy administrative director of the cancer center at Cold Spring Harbor.
All three of their children — Emily, 22, Andrew, 19 and Brian, 18 — have pitched in at different labs over the years. After she graduates from Brandeis this year, Emily plans to attend medical school and has shown an interest in pediatric neurology. Some day, if her father’s treatment proves effective, Emily may be able to do more for children like Dylan Cuevas than doctors have been able to do up until now.

“I definitely hope [Krainer’s treatment] leads to an improvement,” said Debbie Cuevas, who runs the Families of SMA Greater New York Chapter. “I’m happy to see that it’s going into clinical trials.”

A full-time mom to Dylan and Heather, 5, Debbie Cuevas gave up her job at AIG to take care of her children. Cuevas and her husband, Ron, who works for Chips Technology Group in Syosset, have been through some harrowing times. Dylan has had respiratory failure several times and breathes with the assistance of a respirator.

Still, Cuevas remains positive. “Every day we’re on this Earth is a gift,” she said.

Even if Krainer’s research doesn’t provide the single, definitive solution to SMA, Cuevas believes his research, and that of others, can move science and medicine in the right direction.

Some day, for all the families who pray for a cure, she hopes “someone won’t have to utter the words SMA as a diagnosis.”