Radon is a naturally occurring radioactive gas produced when metals like uranium or radium break down in rocks and soil. The gas can make its way into homes through cracks in basement walls and floors, construction joints and gaps around pipes.

“Radon is an indoor air pollutant that can only be detected through testing that measures concentrations of the gas in homes,” said study author Eric A. Whitsel, MD, MPH, of the University of North Carolina in Chapel Hill. “Our research found an increased risk of stroke among participants exposed to radon above — and as many as two picocuries per liter (pCi/L) below — concentrations that usually trigger Environmental Protection Agency recommendations to install a home radon mitigation system.”

The study involved 158,910 female participants with an average age of 63 who did not have stroke at the start of the study. They were followed for an average of 13 years. During the study, there were 6,979 strokes among participants.

To determine radon exposures, researchers linked participants’ home addresses to radon concentration data from the U.S. Geological Survey and the U.S. Environmental Protection Agency (EPA).

The EPA recommends that average indoor radon concentrations do not exceed four picocuries per liter (pCi/L). For concentrations this high, the EPA recommends installing a radon mitigation system to lower radon levels in the home.

Participants were divided into three groups. The highest group had homes in areas where average radon concentrations were more than four pCi/L. The middle group lived in areas with average concentrations between two and four pCi/L. The lowest group lived in areas with average concentrations of less than two pCi/L.

In the group with the highest radon exposures, there were 349 strokes per 100,000 person-years compared to 343 strokes in the middle group and 333 strokes in group with the lowest exposure. Person-years represent both the number of people in the study and the amount of time each person spends in the study.

After adjusting for factors such as smoking, diabetes and high blood pressure, researchers found participants in the highest group had a 14% increased risk of stroke compared to those in the lowest group. Those in the middle group had a 6% increased risk.

“It’s important to note that we found an increased stroke risk among those exposed to radon concentrations as much as two pCi/L below the current lung cancer-based threshold for recommending radon mitigation,” said Whitsel. “More studies are needed to confirm our findings. Confirmation would present an opportunity to improve public health by addressing an emerging risk factor for stroke.”

A limitation of the study was that it included only female participants who were middle age or older and primarily white, so the results may not be the same for other populations.

The study was funded by the National Institute of Environmental Health Sciences and National Heart, Lung, and Blood Institute.

It’s found on farms, in woods, landscapes, fields, hiking trails and other open spaces. So, if you go to those places, you’re susceptible to irritation caused by poison ivy, which can lead to reactions that require medical attention. Worse, most people don’t know poison ivy when they see it.

To find poison ivy before it finds you, University of Florida scientists published a new study in which they use artificial intelligence to confirm that an app can identify poison ivy.

Nathan Boyd, a professor of horticultural sciences at the UF/IFAS Gulf Coast Research and Education Center near Tampa, led the research. Renato Herrig, a post-doctoral researcher in Boyd’s lab, designed the app.

“We were the first to do this, and it was designed as a tool for hikers or others working outdoors,” Boyd said. “The app uses a camera to identify in real-time if poison ivy is present and provides you with a measure of certainty for the detection. It also functions even if you don’t have connectivity to the internet.”

The next step is to make the app commercially available, and there’s no timetable for that yet, Boyd said.

For the study, researchers collected thousands of images of poison ivy from five locations: Alderman’s Ford Conservation Park and Hillsborough River State Park, both in Florida; Eufala National Wildlife Refuge in Alabama; York River State Park in Virgina and Fall Creek Falls State Park in Tennessee.

They labeled images, and in each image, scientists put boxes around the leaves and stems of the plant. The boxed images were critical because poison ivy has a unique leaf arrangement and shape. Scientists use those characteristics to identify the plant.

They then ran the images through AI programs and taught a computer to recognize which plants are poison ivy. They also included images of plants that are not poison ivy or plants that look like poison ivy to be certain the computer learns to distinguish them.

“We believe that by integrating an object-detection algorithm, public health and plant science, our research can encourage and support further investigations to understand poison ivy distribution and minimize health concerns,” Boyd said. In their future work UF/IFAS researchers hope to expand the use of the app to identify more noxious plants.

The fires four years ago triggered widespread tourism shutdowns in many parts of the country in the lead up to the peak Christmas and New Year season, resulting in $1.7 billion direct losses to the tourism industry, which triggered the larger drop in supply chain output.

“These results are an illustration of what can be expected in the future not only in Australia, but in other nations that are vulnerable to climate-change driven disasters,” said Vivienne Reiner, a PhD student with the Centre for Integrated Sustainability Analysis in the Faculty of Science and lead author of the study, published in Economics of Disasters and Climate Change.

“It’s important to note that our study, which measured tourism’s losses through Australian supply chains, did not quantify other economic costs, such as the supply-chain impacts of losses from agriculture or forestry, which were also substantially impacted by the fires,” she said.

While the fires had the biggest impact on Australia’s east coast, the impact from tourism losses was national and felt across the economy, the researchers found.

“Tourism is a vital Australian industry. Before the fires that started in 2019, statistics showed that in rural areas 8 percent, or almost one in 12 people, were employed in jobs connected to the tourism industry,” Ms Reiner said. “As well, tourism is a top export, with travel services responsible for more export income than natural gas in 2018-19.”

Associate Professor Arunima Malik, a co-author who heads the Centre for Integrated Sustainability Analysis and is also affiliated with the Business School, said: “With bushfires increasing compared to other natural disasters and expected to intensify due to climate change, it is important for countries such as Australia to quantify their economic impact as part of routine practice, including supply-chain spillovers.”

Co-author Professor Manfred Lenzen, also with ISA in the School of Physics, said: “Although the losses we calculated only represented a small fraction of the nation’s economic output, Australia’s reputation as a pristine destination could become permanently damaged under global warming, with fewer people travelling within and to Australia in our peak holiday season.”

The research showed varied impact nationwide across the supply chain, including in job losses:

• New South Wales: 3171 jobs
• Victoria: 1430 jobs
• Queensland: 1499 jobs
• South Australia: 516 jobs
• Western Australia: 479 jobs
• Tasmania: 13 jobs
• Australian Capital Territory: 110 jobs
• Northern Territory: 75 jobs.

The researchers warn that the Australian economy could face further losses as the effects from climate change increase.

Ms Reiner said: “As part of the Asia Pacific — the world’s most disaster-prone region — Australian tourism has a lot to gain from climate-change mitigation. In terms of responses, studies such as ours also help indicate hotspots in supply chains where rebuilding may be required in communities and industries.

“By including the entire supply chain in our research, using input-output analysis, we calculated total output losses of $2.8 billion, which is a 61 percent increase on direct damages identified.”

Researchers sometimes grow the cells in a 3D scaffold called a “hydrogel.” This network of proteins or molecules mimics the environment the cells would live in inside the body.

New research led by the University of Washington demonstrates a new class of hydrogels that can form not just outside cells, but also inside of them. The team created these hydrogels from protein building blocks designed using a computer to form a specific structure. These hydrogels exhibited similar mechanical properties both inside and outside of cells, providing researchers with a new tool to group proteins together inside of cells.

The team published these results Jan. 30 in the Proceedings of the National Academy of Sciences.

“In the past 10 years, there’s been a shift in the world of cell biology,” said co-senior author Cole DeForest, a UW associate professor of chemical engineering and of bioengineering. “Classically, folks have attributed much of the cell’s interior organization to membrane-bound organelles, such as mitochondria or the nucleus. But now scientists are realizing that the cell actually has other ways to locally concentrate certain molecules or proteins without using membranes, for example, by protein-protein interactions. This concentrating allows the cell to turn on or off specific functions that can be helpful or ultimately lead to disease.”

DeForest continued: “What I think is pretty exciting here is that we have good mechanical control of our hydrogels — even when they are made inside human cells. This means we can tune them to essentially function as a synthetic version of whatever sequestering phenomenon we want to study, such as how protein aggregation can lead to Alzheimer’s.”

One key element of this research was that the protein building blocks were designed from scratch — they don’t exist anywhere in nature — using computers.

“You can imagine a protein as a string of subunits called amino acids. That string folds up to form a three-dimensional structure. There are 20 different amino acids, and a typical protein is made up of 100 to 200 of them. That makes the system very complex, because how do you know how it’s going to fold?” said co-lead author Rubul Mout, who completed this research as a UW postdoctoral researcher at the Institute for Protein Design and is now a research fellow at Harvard Medical School and Boston Children’s Hospital. “That’s where the computer comes into play — it does calculations to estimate the most likely three-dimensional shape. And similarly, you can tell it what shape you want and it tells you what sequence you need to build the protein.”

To make a variety of hydrogels with different properties, the team used computational design to control how floppy or rigid the protein building blocks were and how the building blocks organized and connected to create the hydrogel. The researchers also used two different methods to link the building blocks together: One linked them irreversibly and the other allowed the proteins to disconnect and reconnect.

“Irreversibly crosslinked systems are going to be intrinsically more stable, making them better for long-term cell culture and functional tissue engineering,” said DeForest, who is also a faculty member with the UW Molecular Engineering and Sciences Institute and the UW Institute for Stem Cell and Regenerative Medicine. “But the reversibly crosslinked systems are more fluid, which may be better for driving specific protein-protein interactions within living cells.”

To determine if the hydrogels in cells had similar characteristics compared to their extracellular counterparts, the researchers examined whether building blocks within the hydrogels could move around. A stiffer hydrogel would be more likely to trap the proteins in one position compared to a more fluid gel. The mechanical properties of each type of hydrogel remained even when inside a cell.

The team plans to further explore this system, including being able to better control how hydrogels form and localize within cells.

The most crucial part of this project, the researchers said, was the collaboration between protein designers and chemical and biological engineers.

“Our cross-disciplinary collaboration with Cole’s group has been very exciting, and has opened up routes to new classes of biomaterials with a wide range of applications,” said co-senior author David Baker, the director of the Institute for Protein Design.