The Daily’s science and technology desk gathers a weekly digest collecting some of the most impactful and interesting research publications and developments at Stanford. Read the latest in this week’s Research Roundup.

Scientists develop method to promote neuron growth

Researchers from Stanford Medicine have found a new way to accelerate the growth of neurons, or nerve cells, according to a study published in Nature on Oct. 2.

Neurons are vital to memory, but they experience cell death just like other human cells. Normally, neuronal stem cells generate new neurons to replace old ones, but those stem cells grow less efficient at generating new neurons as they age — which can lead to memory loss in the long run. 

Led by genetics professor Anne Brunet, researchers used the molecular gene-editing tool CRISPR to look for a gene that, when silenced such that no protein from the gene is translated, activates neuronal stem cells.

They found it. When the gene controlling glucose transport protein GLUT4 is suppressed, the production of that protein decreases and the body’s glucose levels also decrease. This increases the activation of neuronal stem cells, stimulating the growth of new neurons.

The researchers are hopeful they can use this knowledge in the future to create genetic therapies that can silence GLUT4 and promote neuronal growth. They aim to apply their findings to treat various neurological conditions, including brain damage caused by strokes and traumatic brain injuries. 

Ocean absorbs carbon dioxide more slowly than scientists believed

A Stanford-led study has uncovered new details of how microscopic marine life matter absorbs carbon dioxide from the atmosphere. Using observations from a microscope they invented themselves, the researchers described precisely how marine snow — a mixture found in oceans consisting of dead phytoplankton, bacteria and other organic particles — collects carbon dioxide and falls to the ocean floor. 

The study, published in Science on Friday, found that marine snow can produce mucus “parachutes” that slow the sinking of the particles. Manu Prakash, associate professor of bioengineering, and his team used their newly-invented rotating microscope to observe this phenomenon. The organisms are kept in a circular chamber meant to mimic the ocean, while the microscope rotates to accommodate their movements and simulate their travel.

Prakash’s study showed that the ocean absorbs carbon dioxide more slowly than previously understood, due to marine snow mucus impeding its fall to the ocean floor.

The rotating microscope has also helped the team make other scientific observations more reliably. Instead of collecting marine organisms during expeditions and transporting them to the lab, Prakash and his team can simply take the rotating microscope on the expeditions, enabling them to observe the marine organisms in their natural habitats.

“In biology, stripping [life] away from its environment has stripped away any of our capacity to ask the right questions,” Prakash told Stanford Engineering. 

In the future, the team plans to identify the factors contributing to the production of the mucus they observed in the marine snow using the rotating telescope. 

Hurricanes shown to increase mortality for years after striking

While public attention on a hurricane typically lasts only as long as the hurricane itself, a new Stanford study published in Nature shows that higher death rates persist long after a hurricane has ended. 

Typically, official reports only publish death tolls of hurricanes themselves. However, Solomon Hsiang, Stanford professor of environmental social sciences, and Rachel Young, a postdoctoral fellow at UC Berkeley, found that the average U.S. tropical cyclone can cause between 7,000 to 10,000 deaths not directly related to the cyclone itself. A community’s limited access to resources following a hurricane is just one factor that can contribute to this toll.

While the researchers initially believed the effects of a hurricane could last months, after analyzing the distribution of mortality risk across the U.S., they found that harm caused by hurricanes could last for years, depending on the community. The study also found that Black individuals are far more likely to die after a hurricane than white individuals, reinforcing concerns of racial disparities in natural disaster aid.

The researchers are now working to develop a clearer understanding of the causes of abnormally high post-hurricane death rates. They plan to combine data across different disciplines, including economics and social science fields, to help paint a more well-rounded picture of post-hurricane deaths.