Researchers at the Penn State Cancer Institute reviewed cancer registry data collected from 2017 through 2021 and discovered that adults over age 50 living in a 15-county area of South Central Pennsylvania were 57% more likely to be diagnosed with melanoma, the deadliest form of skin cancer, compared to residents elsewhere in the state. The team reported these results on Nov. 14 in the journal JCO Clinical Cancer Informatics.

Charlene Lam, associate professor of dermatology at Penn State Health and co-author of the study, noted that the elevated cases appear in both rural and urban counties. She explained that the higher risk is not limited to isolated locations or people who spend much of their time outdoors.

Agricultural Environments Linked to Elevated Risk

“Melanoma is often associated with beaches and sunbathing, but our findings suggest that agricultural environments may also play a role,” she said. “And this isn’t just about farmers. Entire communities living near agriculture, people who never set foot in a field, may still be at risk.”

The usual suspect — sunlight — was included in the analysis. Yet even after adjusting for ultraviolet radiation levels in Pennsylvania and considering socioeconomic factors, two consistent associations emerged. Counties with more cultivated acreage and counties with greater herbicide use displayed significantly higher melanoma rates.

Herbicides, Biological Effects, and Melanoma Patterns

“Pesticides and herbicides are designed to alter biological systems,” said Eugene Lengerich, emeritus professor of public health sciences at Penn State and senior author on the paper. “Some of those same mechanisms, like increasing photosensitivity or causing oxidative stress, could theoretically contribute to melanoma development.”

According to the analysis, a 10% increase in cultivated land was linked to a 14% rise in melanoma cases across the region. Herbicide exposure showed a similar pattern: a 9% increase in herbicide-treated land corresponded to a 13% increase in melanoma incidence.

Lam emphasized that exposure is not restricted to those handling agricultural chemicals. She explained that these substances can drift on air currents, settle in household dust and enter water sources.

Chemical Drift and Community-Wide Exposure

“Our findings suggest that melanoma risk could extend beyond occupational settings to entire communities,” she said. “This is relevant for people living near farmland. You don’t have to be a farmer to face environmental exposure.”

The study also referenced earlier research showing links between pesticide and herbicide exposure and melanoma, citing evidence that these chemicals can heighten sensitivity to sunlight, interfere with immune responses and damage DNA in non-human animals and plants.

Study Shows Associations, Not Proof of Cause

Benjamin Marks, first author on the paper and a medical and public health student at the Penn State College of Medicine, cautioned that while higher melanoma rates appear in areas with more cropland and herbicide use, the findings do not prove that chemicals used on crops such as corn, soybeans and grains directly cause cancer. Instead, he said the patterns point to a connection that deserves further study.

He added that research of this kind is useful for spotting broad trends, even though it cannot identify individual risk.

“Think of this as a signal, not a verdict,” Marks said. “The data suggest that areas with more cultivated land and herbicide use tend to have higher melanoma rates, but many other factors could be at play like genetics, behavior or access to health care. Understanding these patterns helps us protect not just farmers, but entire communities living near farmland.”

Implications Beyond Pennsylvania

Lam said she hopes to better understand how agricultural practices relate to public health, especially since similar trends have been identified in farming regions of Utah, Poland and Italy. She encouraged anyone concerned about risk to perform routine skin checks and use sun-protective clothing and sunscreen. As part of the next phase of research, she is leading studies in rural communities within the affected area to learn more about farming practices and potential exposure pathways.

“Cancer prevention can’t happen in isolation,” Lengerich said. “This study demonstrates the importance of a ‘One Health’ approach, an understanding that human health is deeply connected to our environment and agricultural systems. If herbicides and farming practices are contributing to melanoma risk, then solutions must involve not just doctors, but farmers, environmental scientists, policymakers and communities working together.”

Other co-authors include Jiangang Liao, professor of public health sciences at Penn State College of Medicine, and Camille Moeckel, a fourth-year medical student and research associate at Penn State College of Medicine.

This work was supported by the MPH Capstone Program and the Medical Student Research Project at the Penn State College of Medicine, along with the University’s Algin B. Garrett Professorship.

Ordinary matter is affected by four known fundamental forces: gravity, electromagnetism, and the strong and weak forces within atoms. The question is whether dark matter responds to the same set of forces. While dark matter is invisible and difficult to detect, it may still follow these familiar laws or possibly be influenced by a fifth force that scientists have not yet identified.

Investigating How Dark Matter Moves Through Gravitational Wells

To explore this possibility, the UNIGE-led team examined whether dark matter sinks into gravitational wells the way ordinary matter does on cosmic scales. Massive objects distort the structure of space, forming these wells. Ordinary matter — planets, stars and galaxies — falls into them according to established physical principles that include Einstein’s general relativity and Euler’s equations. The team wanted to know whether dark matter behaves in the same predictable way.

“To answer this question, we compared the velocities of galaxies across the Universe with the depth of gravitational wells,” explains Camille Bonvin, associate professor in the Department of Theoretical Physics at UNIGE’s Faculty of Science and co-author of the study. “If dark matter is not subject to a fifth force, then galaxies — which are mostly made of dark matter — will fall into these wells like ordinary matter, governed solely by gravity. On the other hand, if a fifth force acts on dark matter, it will influence the motion of galaxies, which would then fall into the wells differently. By comparing the depth of the wells with the galaxies’ velocities, we can therefore test for the presence of such a force.”

Dark Matter Appears to Follow Euler’s Equations

Using this method on modern cosmological data, the researchers found that dark matter moves into gravitational wells in the same manner as ordinary matter, meaning it is consistent with Euler’s equations. “At this stage, however, these conclusions do not yet rule out the presence of an unknown force. But if such a fifth force exists, it cannot exceed 7% of the strength of gravity — otherwise it would already have appeared in our analyses,” says Nastassia Grimm first author of the study and former postdoctoral researcher at the Department of Theoretical Physics at UNIGE’s Faculty of Science who has recently joined the Institute of Cosmology and Gravitation at the University of Portsmouth.

What Comes Next in the Search for New Physics

These early findings represent an important step in refining our understanding of dark matter. The next key objective is to determine whether a subtle fifth force truly affects it. “Upcoming data from the newest experiments, such as LSST and DESI, will be sensitive to forces as weak as 2% of gravity. They should therefore allow us to learn even more about the behavior of dark matter,” concludes Isaac Tutusaus, researcher at ICE-CSIC and IEEC and associate professor at IRAP, Midi-Pyrénées observatory, University of Toulouse, co-author of the study.

The study, titled “Chimpanzees rationally revise their beliefs,” was carried out by an international team that included UC Berkeley Psychology Postdoctoral Researcher Emily Sanford, UC Berkeley Psychology Professor Jan Engelmann and Utrecht University Psychology Professor Hanna Schleihauf. Their results indicate that chimpanzees, similar to humans, adjust their decisions based on how strong the available evidence is, which is a central component of rational thinking.

At the Ngamba Island Chimpanzee Sanctuary in Uganda, the researchers designed an experiment involving two boxes, one of which contained food. The chimps were first given a hint about which box held the reward. Later, they received a clearer and more convincing clue that pointed to the other box. Many of the animals changed their choice after receiving the stronger information.

“Chimpanzees were able to revise their beliefs when better evidence became available,” said Sanford, a researcher in the UC Berkeley Social Origins Lab. “This kind of flexible reasoning is something we often associate with 4-year-old children. It was exciting to show that chimps can do this too.”

Testing Whether Chimps Are Reasoning or Acting on Instinct

To confirm that the animals were truly engaging in reasoning rather than reacting on impulse, the researchers used tightly controlled experiments combined with computational modeling. These methods helped rule out simpler explanations, such as the chimps favoring the most recent clue (recency bias) or simply responding to the easiest cue to notice. The modeling showed that their decisions followed patterns consistent with rational belief revision.

“We recorded their first choice, then their second, and compared whether they revised their beliefs,” Sanford said. “We also used computational models to test how their choices matched up with various reasoning strategies.”

This work challenges long-held assumptions that rationality, defined as forming and updating beliefs based on evidence, belongs only to humans.

“The difference between humans and chimpanzees isn’t a categorical leap. It’s more like a continuum,” Sanford said.

Broader Implications for Learning, Childhood Development and AI

Sanford believes these findings may influence how scientists think about a wide range of fields. Learning how primates update their beliefs could reshape ideas about how children learn and even how artificial intelligence systems are designed.

“This research can help us think differently about how we approach early education or how we model reasoning in AI systems,” she said. “We shouldn’t assume children are blank slates when they walk into a classroom.”

The next phase of the project will apply the same belief revision tasks to young children. Sanford’s team is now gathering data from two- to four-year-olds to see how toddlers handle changing information compared to chimps.

“It’s fascinating to design a task for chimps, and then try to adapt it for a toddler,” she said.

Expanding the Study to Other Primates

Sanford hopes to broaden the work to additional primate species, creating a comparative view of reasoning abilities across evolutionary branches. Her previous research spans topics from empathy in dogs to numerical understanding in children, and she notes that one theme continues to stand out: animals often demonstrate far more cognitive sophistication than people assume.

“They may not know what science is, but they’re navigating complex environments with intelligent and adaptive strategies,” she said. “And that’s something worth paying attention to.”

Other members of the research team include: Bill Thompson (UC Berkeley Psychology); Snow Zhang (UC Berkeley Philosophy); Joshua Rukundo (Ngamba Island Chimpanzee Sanctuary/Chimpanzee Trust, Uganda); Josep Call (School of Psychology and Neuroscience, University of St Andrews); and Esther Herrmann (School of Psychology, University of Portsmouth).

These results may help clarify why people who combine the two substances more often experience symptoms such as anxiety and depression, and why attempts to quit cannabis tend to be more difficult for them than for people who avoid tobacco.

“This is the first evidence in humans of a molecular mechanism that may underlie why people who use both cannabis and tobacco experience worse outcomes,” said lead author Rachel Rabin, Associate Professor in McGill’s Department of Psychiatry and researcher at the Douglas.

“Identifying this mechanism is an important step toward finding targets for future medications to treat cannabis use disorder, especially among those that co-use tobacco. Right now, the only available treatments are behavioral therapies such as counseling,” she said.

Co-Use Common Even as Tobacco Use Declines

In Canada, roughly one in 20 people who used cannabis within the past year are considered at risk for cannabis use disorder. Among people who consume cannabis more often, the rate jumps to about one in three.

The researchers note that tobacco use is decreasing overall, yet the majority of cannabis users still report using tobacco as well. Rabin explained that most previous studies focused on each substance separately, leaving a major gap that this early-stage research is beginning to fill.

Changes in the Brain’s “Bliss Molecule” System

PET scans showed that people who used both cannabis and tobacco had elevated levels of FAAH when compared to those using cannabis alone. FAAH is an enzyme that breaks down anandamide, a naturally occurring compound often described as the “bliss molecule” because of its influence on mood and stress responses. Higher FAAH levels mean lower anandamide levels, a pattern that has previously been linked to anxiety, depression and higher relapse rates among people trying to stop using cannabis.

Small Study Offers Early Clues

The analysis involved 13 young adults. Eight used only cannabis, while five used cannabis and smoked cigarettes every day. Cannabis use averaged slightly above one gram per day. Cigarette intake ranged from one to 12 per day.

Because the data was originally gathered for an unrelated project, there was no tobacco-only group for comparison. This means the changes could potentially be caused by tobacco alone, although the researchers believe the results point to a more complex interaction.

“What surprised us was how strong the effect was, and how different it was from those who only used cannabis, compared to those who used both tobacco and cannabis,” said co-author Romina Mizrahi, Professor of Psychiatry and director of the McGill Research Center for Cannabis.

Next Steps in Understanding Tobacco’s Role

The team is now recruiting people who smoke cigarettes and people who vape nicotine for a follow-up project that will explore whether similar brain changes appear in the absence of cannabis.

“A preliminary investigation of tobacco co-use on endocannabinoid activity in people with cannabis use” by Rachel Rabin, Joseph Farrugia, Ranjini Garani and Romina Mizrahi was published in Drug and Alcohol Dependence Reports.

The study received funding from the National Institute of Mental Health.

Researchers at University of Utah Health (U of U Health) have discovered that fatty molecules called ceramides initiate AKI by damaging the mitochondria that supply energy to kidney cells. By using a backup drug candidate designed to alter how ceramides are processed, the team protected mitochondrial structure and prevented kidney injury in mice.

“We completely reversed the pathology of acute kidney injury by inactivating ceramides,” says Scott Summers, PhD, distinguished professor and Chair of the Department of Nutrition and Integrative Physiology in the University of Utah College of Health and senior author on the study. “We were stunned — not only did kidney function stay normal, but the mitochondria were unscathed,” Summers says. “It was truly remarkable.”

The results are published in Cell Metabolism.

Ceramide spikes may serve as an early warning

Earlier studies from the Summers lab showed that ceramides can harm organs such as the heart and liver. When the researchers measured ceramides in AKI models, they found a strong connection: levels rose sharply after injury in both mice and in human urine samples.

“Ceramide levels are very elevated in kidney injury,” says Rebekah Nicholson, PhD, first author on the work, who completed the research as a graduate student in nutrition and integrative physiology at U of U Health and is now a postdoctoral fellow at the Arc Institute. “They go up quickly after damage to the kidneys, and they go up in relation to the severity of the injury. The worse the kidney injury is, the higher the ceramide levels will be.”

These findings indicate that urinary ceramides could act as an early biomarker for AKI, giving clinicians a tool to identify vulnerable patients, including those preparing for heart surgery, before symptoms begin. “If patients are undergoing a procedure that we know puts them at high risk of AKI, then we can better predict whether or not they’re actually going to have one,” Nicholson says.

Altering ceramide production protects kidney function

The team nearly eliminated kidney injury in a mouse model by modifying the genetic program that controls ceramide production. This change produced “super mice” that did not develop AKI even under conditions that typically cause severe damage.

The researchers then tested a ceramide-lowering drug candidate created by Centaurus Therapeutics, a company co-founded by Summers. Mice treated ahead of time avoided kidney injury, maintained normal kidney function, remained active, and had kidneys that appeared close to normal under the microscope. Nicholson notes that their model places extreme stress on the kidneys, making it “really remarkable that mice were protected from the injury.”

“These mice looked incredible,” Summers adds.

The team found that ceramides harm mitochondria, the parts of the cell responsible for energy production. Damaged mitochondria in kidney cells become distorted and function poorly. Adjusting ceramide production, whether genetically or with the drug, kept mitochondria intact and working even under strain.

Potential for future therapies targeting mitochondrial health

Summers explains that the compound used in this study is closely related to, but not identical to, the ceramide-lowering drug that has entered human clinical testing. He emphasizes that mouse results do not always predict human outcomes and that further research is needed to confirm safety.

“We’re thrilled by how protective this backup compound was, but it’s still preclinical,” Summers says. “We need to be cautious and do our due diligence to make sure this approach is truly safe before moving it into patients.”

Even so, the researchers are encouraged by the findings. If the results extend to people, the drug could potentially be administered ahead of time to individuals who face a high risk of AKI, including patients undergoing heart surgery, where about one quarter experience the condition.

Because the drug appears to work by maintaining mitochondrial health, the team believes that the approach may have relevance for other disorders linked to mitochondrial dysfunction.

“Mitochondrial problems show up in so many diseases — heart failure, diabetes, fatty liver disease,” Summers says. “So if we can truly restore mitochondrial health, the implications could be enormous.”

The results are published in Cell Metabolism as “Therapeutic Remodeling of the Ceramide Backbone Prevents Kidney Injury.”

Funding and disclosures

This work was supported by a NCRR Shared Instrument Grant, the Kidney Precision Medicine Project, and several branches of the National Institutes of Health, including the National Cancer Institute (P30CA042014, CA272529), the National Institute of Diabetes and Digestive and Kidney Diseases (DK115824, DK116888, DK116450, DK130296, DK108833, DK112826, 1F31DK134088 and 5T32DK091317), and the National Institute of General Medical Sciences (3R35GM131854 and 3R35GM131854-04S1). Additional support came from the Juvenile Diabetes Research Foundation (JDRF 3-SRA-2019-768-A-B and JDRF 3-SRA-2019-768-A-B to WLH), the Burroughs Wellcome Fund Postdoctoral Diversity Enrichment Program (1058616), the American Diabetes Association, the American Heart Association, the Margolis Foundation, and the University of Utah Diabetes and Metabolism Research Center. The authors state that the content is their responsibility and does not necessarily reflect the views of the National Institutes of Health.

Scott Summers and Jeremy Blitzer are co-founders and shareholders of Centaurus Therapeutics. Liping Wang is also a shareholder. DN and Blitzer are listed as inventors on US Patents 1177684, 11597715, and 11135207 licensed to Centaurus Therapeutics, Inc.