Radiation repellent, blood test in your pocket, and magnetic nerve cells. This week’s coolest things are master manipulators.
Seeing the Forest for the Trees

What is it? In a surprise, researchers in Israel found that planting forests in arid areas to fight global warming could actually make it worse.
Why does it matter? Afforestation — or planting forests where there weren’t any before — is a popular approach for pulling carbon emissions from the atmosphere. “When we began the research, we expected to show that extensive planting of forests in semi-arid areas would significantly slow down climate warming,” said Yohay Carmel, an environmental engineering professor at Technion Israel Institute of Technology and senior author of a Science study. “But our study disproved this accepted hypothesis. It is disappointing indeed.”
How does it work? While tree planting can mitigate the effects of planet-warming gases, the researchers found that replacing barren land with forests can increase heat trapped in the atmosphere. This is due to the albedo effect: Lighter-colored areas (such as glaciers and deserts) reflect more of the sun’s radiation than dark surfaces, including forests. Planting trees in large swaths of the earth’s semi-arid regions would end up increasing temperatures, the researchers concluded.

What is it? An international team of researchers has identified a potential way to protect astronauts from cosmic radiation: synthetic hibernation.
Why does it matter? One of the biggest risks of long-term space exploration is damage from radiation. Putting astronauts into torpor — the slowed-down biological state of hibernation — could increase their resistance to radiation’s effects, the researchers conclude in Scientific Reports.
How does it work? When animals hibernate, their heart rates, metabolism, breathing, and gene activity slow, and body temperature drops. Reproducing that state in rats, which do not hibernate in nature, protected their tissues against lethal doses of high-energy ion radiation. “It could thus be an effective strategy to protect humans as they explore the solar system,” said Marco Durante, a co-author from GSI Helmholtzzentrum in Germany.
What is it? University of Washington scientists created a test for blood clotting that requires just a drop of blood and a smartphone.
Why does it matter? Some people with heart issues have to monitor blood coagulation with frequent doctor visits. “The devices that exist in hospitals to test for this haven’t changed much for 20 or 30 years,” said Shyamnath Gollakota, senior author of a study in Nature Communications. “But smartphones have been changing a lot. They have vibration motors, they have a camera, and these sensors exist on almost any smartphone.”
How does it work? A person uses a finger prick to draw a drop of blood and inserts it into a tiny cup. The cup fits into a smartphone attachment under the camera lens. Using the phone’s vibrating motor, the cup shakes the sample while the camera tracks movement of a floating piece of copper within. When the copper stops moving freely, it means the blood has coagulated.

What is it? Researchers at the University of Pennsylvania’s medical school tested a potential universal flu shot.
Why does it matter? There are 20 known flu strains, and each flu season, scientists tailor vaccines to the strains predicted to circulate that year. The shots are less effective when those predictions miss the mark. As such, they “offer little protection against pandemic influenza virus strains,” the UPenn team wrote in Science. They are working on a single vaccine to guard against illness from any strain of influenza.
How does it work? The scientists used mRNA vaccine technology, like that in COVID-19 vaccines. The genetic data in the vaccines encodes for fragments of proteins found on the surfaces of all 20 flu strains that cause illness each year. When tested in rats and ferrets, the shots were 100% effective against flu viruses with proteins that closely matched the vaccine’s encoded proteins and still 80% effective against another strain with different variants of those proteins. Today’s flu shots reduce the chances of needing treatment by 40% to 60%.

What is it? Bioengineers at Israel’s Bar-Ilan University created magnetically controlled brain cells.
Why does it matter? When neurons — nerve cells of the brain and nervous system — are damaged, they usually can’t repair themselves. The researchers’ lab-grown neurons could pave the way toward regenerating broken neural circuits in the body.
How does it work? The researchers embedded magnetic materials into neural progenitor cells, which are like stem cells for neurons. They used a magnetic field array to organize the matured cells into a three-dimensional network that formed connections and sent electrical impulses. “They can be used as experimental ‘mini-brains’ and serve as a model for the study of medicinal drugs, for investigating communication between tissues, and as a way to build artificial networks for interfaces between engineering and biological components,” said Reut Plen, first author of a study in Advanced Functional Materials.