These findings provide new insight into age-related inflammation and help explain why something as simple as a cough can sometimes lead to hospitalization in older individuals.

Aging Lung Cells and Inflammation

To explore what changes in older lungs, researchers focused on fibroblasts, the structural cells that help maintain lung tissue. In experiments with young mice, they activated a stress signal typically linked to aging. This caused the lungs to develop clusters of inflamed cells, including some marked by the GZMK gene, which was first identified in severe COVID-19 cases. Scientists believe future treatments could target these cells to interrupt the harmful cycle known as inflammaging.

“We were surprised to see lung fibroblasts working hand-in-hand with immune cells to drive inflammaging,” said Tien Peng, MD, a professor of Medicine and a member of the Cardiovascular Research Institute and Bakar Aging Research Institute at UCSF. “It suggests new ways to intervene before patients progress to severe inflammation that can require intubation.”

Peng is the senior author of the study, published in Immunity on March 27. Nancy Allen MD, PhD, a clinical fellow in the Pulmonary and Critical Care Division in the UCSF Department of Medicine, is the first author.

Fibroblasts and the NF-kB Pathway

Fibroblasts play a key role in keeping the lungs’ airways and air sacs stable and functional. However, they are also known to contribute to inflammation in conditions such as COPD. The research team wanted to determine whether signals from these cells could disrupt otherwise healthy lungs.

They examined a pathway called NF-kB, which is commonly associated with aging-related diseases. When activated, fibroblasts signaled macrophages in the lungs to initiate an immune response. This response then drew additional immune cells from the bloodstream, including those marked by GZMK.

Although these GZMK cells were not effective at fighting infection, they were still able to damage lung tissue.

Immune Cell Clusters and Lung Damage

After these clusters of immune cells formed, the young mice developed severe symptoms when infected, resembling the response typically seen in older adults. When researchers used a genetic method to remove the GZMK cells, the mice were better able to tolerate the infection.

This finding suggests that aging lung tissue itself may be a major driver of harmful inflammation.

The researchers also examined lung tissue from older patients hospitalized with COVID-related ARDS (acute respiratory distress syndrome). These samples contained similar clusters of inflamed cells to those observed in the mice. Patients with more severe illness had a greater number of these clusters, while healthy donor lungs showed none.

“We saw during COVID that our most vulnerable patients no longer had the infection but still had persistent and devastating lung inflammation,” Peng said. “This circuit of dysfunction between lung and immune cells makes for a promising new therapeutic target.”

Researchers at the University of Illinois Urbana-Champaign are studying how microwave frying can improve the way French fries are made. Their findings suggest that combining traditional frying with microwave heating may reduce oil absorption while maintaining the crispy texture people expect. This approach could also shorten cooking times, making it appealing for large-scale food production.

“Consumers want healthy foods, but at the time of purchase, their cravings often take over. High oil content adds flavor, but it also contains a lot of energy and calories. My research team studies frying with the aim of obtaining lower fat content without significant differences in taste and texture,” said principal investigator Pawan Singh Takhar, professor of food engineering in the Department of Food Science and Human Nutrition, part of the College of Agricultural, Consumer and Environmental Sciences at U of I.

Takhar and doctoral student Yash Shah outlined their findings in two recent studies focused on how microwave frying changes what happens inside French fries during cooking.

Inside the Frying Process

In one study, the team partnered with researchers at Washington State University to use a specially designed microwave fryer. This system operated at two frequencies, 2.45 gigahertz (similar to a regular microwave oven) and 5.8 gigahertz.

To prepare the samples, potatoes were rinsed, peeled, cut into strips, blanched, and salted. The strips were then fried in soybean oil heated to 180 degrees Celsius. During and after frying, the team measured temperature, pressure, volume, texture, moisture, and oil content.

A key challenge in frying is preventing oil from entering the food, Takhar explained. Early in the process, the potato’s pores are filled with water, leaving no space for oil. As cooking continues, that water evaporates, creating empty spaces that allow oil to be drawn in through negative pressure.

“Think about a straw in a drink. If you push air into the straw, it creates positive pressure and any liquid will be pushed out. But if you suck on the straw, the liquid moves upward. Now imagine food materials have lots of tiny straws. When there is positive pressure, the oil stays out. But if there is negative pressure, the oil starts moving in,” Takhar explained.

How Microwaves Help Reduce Oil Absorption

Much of the frying process occurs under negative pressure, which increases the tendency for oil to be pulled into the food. The researchers aimed to extend the time under positive pressure and reduce the period when negative pressure dominates.

“When we heat something in a conventional oven, the heat moves from outside to inside, but a microwave oven heats from the inside out, because the microwaves penetrate everywhere in the material. The microwaves oscillate water molecules, causing more vapor formation and thus shifting the pressure profile towards the positive side. The higher pressure in microwaves helps reduce oil penetration,” Takhar said.

Because microwaves generate heat throughout the food, they promote vapor formation and help maintain internal pressure that keeps oil from being absorbed as easily.

Faster Cooking and Less Oil

Alongside the experimental work, the researchers developed mathematical models to better understand how different factors influence frying. This modeling allowed them to examine temperature, pressure, moisture, texture, volume, and oil content under different conditions, including 2.45 GHz, 5.8 GHz, and conventional frying.

The results showed that microwave frying led to quicker moisture loss, reduced cooking times, and lower oil uptake overall.

However, microwave frying alone does not produce the desired texture.

“However, if you just use microwave frying, you get soggy food. To obtain a crispy texture and taste, you need conventional heating. Therefore, we propose combining the two approaches in the same unit. Conventional heating maintains the crispiness, while microwave heating lowers the oil intake,” Takhar said.

A Practical Solution for the Food Industry

The researchers suggest that existing industrial fryers could be upgraded with microwave generators, which are relatively low cost and widely available. This makes the combined method a practical option for large-scale food production.

The findings were published in two papers. The first, “The Effect of Conventional and Microwave Frying on the Quality Characteristics of French Fries,” appeared in the Journal of Food Science and was authored by Yash Shah, Xu Zhou, Juming Tang, and Pawan Singh Takhar.

The second paper “Predicting the quality changes during microwave frying of food biopolymers by solving the hybrid mixture theory-based unsaturated transport, and electromagnetics equations,” was published in Current Research in Food Science.

The research was funded by USDA National Institute of Food and Agriculture (Awards 2020-67017-31194, ILLU-698-308, and ILLU-698-926).

One emerging solution is optical wireless communication, which uses light instead of radio waves to transmit data. Light offers significantly more available bandwidth, avoids interference with existing wireless systems, and can be directed with high precision. These advantages make it especially appealing for indoor spaces like offices, homes, hospitals, data centers, and public venues where many users need fast connections at the same time.

In a study published in Advanced Photonics Nexus, researchers developed a compact optical wireless transmitter that delivers both extremely high speeds and improved energy efficiency. The system is built around a tiny chip containing an array of semiconductor lasers, combined with an optical design that carefully controls how light is distributed. Together, these components create a scalable platform for high-capacity indoor wireless communication.

Tiny Laser Array Sends Massive Data

At the core of the system is a custom-designed 5 × 5 array of vertical-cavity surface-emitting lasers, known as VCSELs. These infrared lasers are commonly used in data centers and sensing technologies because they are efficient and capable of operating at very high speeds. They can also be manufactured in large arrays using standard semiconductor fabrication methods.

Each laser in the array can be controlled independently and transmit its own stream of data. By running multiple lasers at the same time, the system dramatically increases total data capacity compared to a single light source. The entire array fits on a chip smaller than a millimeter, making it suitable for compact wireless access points and potentially small enough to integrate into devices such as smartphones.

The researchers produced the chip using established semiconductor techniques and mounted it on a custom circuit board. Early testing showed consistent performance across the array, with stable output and support for high-speed data transmission.

Record-Breaking Optical Wireless Speeds

To test the system, the team created a free-space optical link spanning two meters. Each laser transmitted data using a modulation method that splits information into multiple closely spaced frequency channels. This approach maximizes bandwidth efficiency and adapts to changes in signal quality.

Out of the 25 lasers, 21 were active during testing. Individual lasers reached data rates between roughly 13 and 19 gigabits per second. Combined, the system achieved a total data rate of 362.7 gigabits per second. This is among the highest reported speeds for a chip-scale optical wireless transmitter paired with a free-space receiver.

The researchers noted that performance was limited by the bandwidth of the commercial photodetector used in the experiment. With more advanced receivers, the same system could potentially reach even higher speeds.

Shaping Light for Multiuser Connections

Using many light beams at once introduces a key challenge: preventing overlap that can cause interference. To solve this, the researchers designed an optical system that precisely shapes and directs each beam.

A microlens array first aligns and straightens the light from each laser. Additional lenses then organize the beams into a structured grid of square illumination areas at the receiving surface. This layout ensures that each beam covers a specific region with minimal overlap.

Tests showed that the light distribution achieved more than 90 percent uniformity across the illuminated area at a distance of two meters. This structured approach allows different beams to be assigned to different users or devices within the same room.

The team also demonstrated multiuser capability by activating several lasers at once. In a test with four simultaneous beams, each connection remained stable, delivering a combined data rate of about 22 gigabits per second. The results confirm that multiple optical links can operate at the same time without significant interference.

Lower Energy Use Than Wi-Fi

Improving energy efficiency is critical as wireless data demand continues to rise. Traditional radio-based systems require more power to support higher speeds, increasing both costs and environmental impact.

The optical wireless system uses laser sources that are inherently energy efficient and capable of high-speed operation without complex power demands. As a result, it consumes much less energy per bit of transmitted data compared to conventional Wi-Fi systems. Measurements showed an energy use of about 1.4 nanojoules per bit, roughly half that of leading Wi-Fi technologies under similar conditions.

Complementing Existing Networks

Researchers emphasize that optical wireless technology is not meant to replace Wi-Fi or cellular networks. Instead, it can work alongside them, handling high-capacity data traffic in indoor environments and reducing congestion on radio-based systems.

Looking ahead, similar systems could be built into ceilings, lighting fixtures, or wireless access points, delivering fast, secure, and energy-efficient connections to many users simultaneously. By combining compact laser arrays, high-speed transmission, and precise optical control, this approach offers a practical path toward next-generation indoor wireless networks that deliver greater performance without increasing energy consumption.

Research led by Colorado State University Ph.D. student Robert J. Madden shows that dice, gambling, and games of chance have deep roots in Native American culture, stretching back at least 12,000 years. The earliest examples come from Late Pleistocene Folsom-period sites in Wyoming, Colorado, and New Mexico. These artifacts are more than 6,000 years older than comparable dice found in the Old World.

“Historians have traditionally treated dice and probability as Old World innovations,” Madden said. “What the archaeological record shows is that ancient Native American groups were deliberately making objects designed to produce random outcomes, and using those outcomes in structured games, thousands of years earlier than previously recognized.”

What Ice Age Dice Looked Like

The oldest specimens identified in the study date to roughly 12,800-12,200 years ago. Unlike modern six-sided dice, these objects were two-sided pieces known as “binary lots.” They were carefully shaped from bone into small, handheld forms that were flat or slightly rounded, often oval or rectangular, and designed to be tossed together onto a surface.

Each piece had two distinct faces, marked by differences in color, texture, or added designs, similar to heads and tails on a coin. One side served as the “counting” face. When thrown, each piece would land showing one side or the other, producing a binary (two-outcome) result. Players cast multiple pieces at once, and the outcome depended on how many landed with the counting face up.

“They’re simple, elegant tools,” Madden said. “But they’re also unmistakably purposeful. These are not casual byproducts of bone working. They were made to generate random outcomes.”

A New Method to Identify Ancient Dice

To move beyond guesswork, the study introduces an attribute-based morphological test, a structured checklist of physical characteristics used to identify dice in archaeological collections. This method is based on a comparative analysis of 293 sets of historic Native American dice recorded by ethnographer Stewart Culin in his 1907 Bureau of American Ethnology monograph, Games of the North American Indians.

Using this framework, the study revisits artifacts that had previously been labeled as possible “gaming pieces” or ignored entirely. By applying consistent criteria, Madden was able to determine whether these objects fit the definition of dice.

In many cases, the items had been known for decades but were never evaluated within a broader pattern. With this new approach, the study identifies more than 600 diagnostic and probable dice from sites covering every major period of North American prehistory, from the Late Pleistocene through and after European contact.

“In most cases, these objects had already been excavated and published,” Madden said. “What was missing wasn’t the evidence, it was a clear, continent-wide standard for recognizing what we were looking at.”

The earliest examples were also examined directly in museum collections at the Smithsonian Institution, the University of Wyoming Archaeological Repository, and the Denver Museum of Nature and Science.

Rethinking the Origins of Probability

Dice games are often considered humanity’s earliest structured interaction with randomness, laying the groundwork for probability theory, statistics, and scientific reasoning. Until now, scholars believed these practices originated in complex Old World societies around 5,500 years ago.

The new findings point to a much earlier and more widespread origin.

“These findings don’t claim that Ice Age hunter-gatherers were doing formal probability theory,” Madden said. “But they were intentionally creating, observing, and relying on random outcomes in repeatable, rule-based ways that leveraged probabilistic regularities, such as the law of large numbers. That matters for how we understand the global history of probabilistic thinking.”

A Long-Lasting Cultural Tradition

The research also highlights how widespread and enduring dice games have been in Native American cultures. Evidence of dice appears at 57 archaeological sites across a 12-state region, spanning Paleoindian, Archaic, and Late Prehistoric periods, and reflecting a wide range of cultural traditions and lifestyles.

Madden suggests that this long history points to the important social role of games of chance. “Games of chance and gambling created neutral, rule-governed spaces for ancient Native Americans,” he said. “They allowed people from different groups to interact, exchange goods and information, form alliances, and manage uncertainty. In that sense, they functioned as powerful social technologies.”

About the Study

The article, “Probability in the Pleistocene: Origins and Antiquity of Native American Dice, Games of Chance, and Gambling,” will appear in American Antiquity, published by Cambridge University Press on behalf of the Society for American Archaeology.