Research

Rising tides

Scientists have long known that the retreat of the last ice age initiated a rise in sea levels, but the degree of the increase has been unclear, making it difficult to predict future fluctuations. Now a report in Nature, coauthored by Carling Hay, an assistant professor of earth and environmental sciences, details the rate and location of changes along the East Coast. A research team that, in addition to Hay, included scientists from Woods Hole Oceanographic Institution and Harvard used computer modeling and statistical analysis to produce a comprehensive picture of coastal Atlantic sea levels over the past hundred years. The scientists determined that the sea level has risen some 1.5 feet in the Virginia/Carolinas area, while the rise has been approximately half a foot along the coast of Maine. The changes have been triggered by the very gradual and uneven collapse of Earth’s elastic crust as it recovers from the last ice age. Although only one factor affecting ocean levels (climate change is a significant contributor), such processes, the team wrote, “will persist at similar rates for centuries.”

Speech therapy

Could computer science lead to improved communication and social skills for the often-overlooked population of adults affected by autism spectrum disorder (ASD)? That’s the hope of Emily Prud’hommeaux, associate professor of computer science. Prud’hommeaux and her colleagues at the University of Rochester and the Oregon Health and Science University have received a three-year National Institutes of Health grant to study “high-functioning” adults with ASD. This community includes people who have levels of education comparable to their neurotypical peers and the ability to live on their own, but who “often have difficulty finding employment and making friends,” Prud’hommeaux said. As part of the project, the researchers will ask groups of ASD adults to undertake a set of communication tasks—retelling a story, for example, or describing a picture. Machine-learning technology will then be used to identify atypical patterns in the responses of the study subjects. The results of this research could lead to software that enables therapists to recognize irregularities in an individual’s speech, and to develop therapies targeted to that person’s specific needs.

Current affairs

A breakthrough device from a team led by Boston College scientists could one day enable solar energy systems that are dramatically more efficient than current technologies. As reported in Nature Materials, the researchers, who also come from Switzerland, Germany, and California, used a recently discovered material called a Weyl semimetal to design the device, which is smaller than a single bacterium. Kenneth Burch, associate professor of chemistry and lead author of the paper, said the device, which employs the semimetal tantalum arsenide, allows light to be converted directly to electricity without the need for complex doping or fabrication. Testing results were more than ten times greater than had been previously achieved, Burch said, “far larger than we dreamed.” In addition to more-efficient solar energy systems, the breakthrough could also lead to novel thermal imaging devices such as those used by firefighters to detect heat through smoke.

The CEO’s incentive

Cuts in the personal capital gains tax rate can bring about significant (and unexpected) shifts in the corporate strategies that CEOs pursue, according to research by a professor at the Carroll School of Management. Assistant professor of accounting Benjamin Yost looked at the risk profiles of corporations before and after cuts in state and federal capital gains tax rates. He found that when a drop in long-term capital gains tax rates reduced personal tax liability, CEOs with large holdings in their companies sold shares, thereby making their personal wealth less tied to corporate performance. Subsequently, the companies became less risk-averse (for instance, investing more in R&D or taking on more debt), with greater volatility in earnings and stock prices. Yost notes his findings are not a prescription for capital gains tax cuts or the resulting corporate decisions. But his research does have a message for corporate boards, which he says should be aware of “the role played by managers’ personal taxes in influencing incentive alignment.” ◽