In Review: Discover

BOTH SIDES NOW: Rochester-developed coatings simultaneously reflect and transmit the same wavelength. (Photograph: J. Adam Fenster)

Researchers at the Institute of Optics along with colleagues at Case Western Reserve University describe in Nature Nanotechnology a new class of optical coatings, so-called Fano-resonance optical coatings, that can simultaneously reflect and transmit the same wavelength, or color.

“Before our technology, the only coating that could do this was a multilayered dielectric mirror, that is much thicker, suffers from a strong angular dependence, and is far more expensive to make,” says Chunlei Guo, a professor of optics at the institute. “Our coating can be a low-cost and high-performance alternative.”

The researchers—including postdoctoral associates Mohamed ElKabbash (lead author) and Julia Zhang, and James Rutledge ’19, who worked on the project as an undergraduate—say the technology could lead to a sixfold increase in the life of photovoltaic cells, devices that convert light energy directly into electricity. The rest of the spectrum “is absorbed as thermal energy, which could be used in other ways, including energy storage for nighttime, electricity generation, solar-driven water sanitation, or heating up a supply of water,” Guo says.

He adds that the coating will likely have more applications; but as with many discoveries, “it will take a little bit of time to further study this and come up with more applications.”

—Bob Marcotte

Cracking the Secrets to the Interior of Exoplanets

An international team of researchers from Lawrence Livermore National Laboratory, the University of Oxford, and the Laboratory for Laser Energetics at Rochester has developed the first model of carbon structures that may make up planets outside the solar system. In developing the model, the team measured carbon at the highest pressures ever achieved in a laboratory.

As the fourth most abundant element in the universe, carbon is a building block for all known life and forms the interior of carbon-rich exoplanets. Graphite and diamond are the most common carbon structures found at ambient pressures, but scientists have long predicted that there are several other structures of carbon that could be found at pressures greater than that in Earth’s core.

As reported in the journal Nature, the researchers succeeded in measuring carbon at pressures five times the pressure in Earth’s core. That’s nearly double the maximum pressure at which carbon’s crystal structure has ever been directly probed. They found that even under that condition, solid carbon retains its diamond structure far beyond its range of predicted stability, resulting in large energy barriers that hinder carbon’s conversion to other possible structures. “The diamond phase of carbon appears to be the most stubborn structure ever explored,” says Ryan Rygg, an assistant professor of mechanical engineering and of physics and a senior scientist at the LLE.

The findings could have implications for carbon in the deep interiors of planets.

“Now we anticipate the diamond structure of carbon will persist over a much greater range of planetary conditions than we previously thought,” Rygg adds.

—Lindsey Valich

How Does the Brain ‘Comprehend’ Spoken Language? AI Helps Map Meaning

A study by Rochester researchers describes the complex network within the brain that comprehends the meaning of a spoken sentence.

“The meaning of a sentence is more than the sum of its parts,” says Andrew Anderson, a research assistant professor in the Del Monte Institute for Neuroscience and lead author of the study. “Take a very simple example: ‘The car ran over the cat’ and ‘The cat ran over the car.’ Each sentence has exactly the same words, but those words have a totally different meaning when reordered.”

Published in the Journal of Neuroscience, the study is an example of how the application of artificial neural networks, or AI, are enabling researchers to unlock the complex signaling in the brain that underlies functions such as processing language. The researchers recorded brain activity in study participants who read sentences while undergoing functional MRI (fMRI). The scans showed activity in the brain spanning a network of different regions. Using an AI model developed by Facebook that’s trained to produce unified semantic representations of sentences, the researchers were able to predict patterns of fMRI activity reflecting the encoding of sentence meaning across those brain regions.

Anderson and his team, which included School of Arts & Sciences faculty members in the Departments of Brain and Cognitive Sciences and in Linguistics, believe the findings could be helpful in understanding several clinical conditions.

The team says the model may also be useful in predicting brain activity in the production of spoken sentences.

—Kelsie Smith Hayduk

A Clue to Alleviating Frailty in Cancer Patients

“Frailty,” while part of common parlance, is also the name of a medical condition. Characterized by weakness, fatigue, weight loss, and slow walking speed, it’s often associated with cancer and its treatments. Understanding frailty and how to prevent it is important to improving quality of life for people at any age who are facing disease.

In a study of women with breast cancer, Medical Center researchers found that patients were more likely to exhibit frailty if they showed higher levels of inflammatory markers in the blood prior to chemotherapy.

“Our findings confirm that oncologists should consider inflammation and frailty in their patients and perhaps personalize treatment, especially in older adults,” says Nikesha Gilmore, a research assistant professor of surgery who conducts studies for the Wilmot Cancer Institute’s Cancer Prevention and Control program.

The mean age of the women in the study was 53, suggesting that frailty can occur among younger patients, too. Gilmore adds that future research should focus on whether it’s possible to reduce inflammation before treatment begins.

—Leslie Orr

Age-Related Macular Degeneration: A Step toward a Cure

Rochester researchers have made an important breakthrough in the quest for a cure for age-related macular degeneration (AMD), the leading cause of blindness in adults 50 years of age or older: they’ve created the first three-dimensional (3D) lab model that mimics the part of the human retina affected in macular degeneration.

Their model combines stem- cell-derived retinal tissue and vascular networks from human patients with bi-oengineered synthetic materials in a three-dimensional “matrix.” Notably, using patient-derived 3D retinal tissue allowed the researchers to investigate the underlying mechanisms involved in advanced neovascular macular degeneration, known as the wet form of macular degeneration, which is the more debilitating and blinding form of the disease.

The lab of Danielle Benoit, professor of biomedical engineering and director of the Materials Science Program, engineered the synthetic materials for the matrix and helped configure it, as described in a paper in Cell Stem Cell.

Ruchira Singh, an associate professor of ophthalmology at the Flaum Eye Institute, says the model suggests wet-AMD-related changes in the human retina could be targeted with drugs.

“Once we have validated this over a large sample,” Singh says, “the next hope would be to develop rational drug therapies and potentially even test the efficacy of a specific drug to work for individual patients.”

—Bob Marcotte