Friday, September 20, 2024

Mental health concerns are a huge part of primary care practice

Family physicians are on the front line for handling mental illnesses across the lifespan

Duke University

Incidence of Health Concerns in Primary Care Encounters — image:
A bar chart from the academic paper showing the incidence of various health complaints in visits to primary care physicians. Psychological concerns are occurring in more than 10 percent of visits, second only to muskuloskeletal and cardiovascular complaints.
view more
Credit: CITATION: “Nationwide Analysis of 350 million Patient Encounters Reveals a High Volume of Mental-Health Conditions in Primary Care,” Avshalom Caspi, Renata Houts, Terrie Moffitt, Lea Richmond-Rakerd, Matthew Hanna, Hans Fredrik Sunde, Fartein Ask Torvik. Nature Mental Health, Sept. 19, 2024. DOI: 10.1038/s44220-024-00310-5

DURHAM, N.C. – An examination of millions of patient visits to primary care physicians shows that mental health concerns are second only to musculoskeletal complaints in everyday care. One in nine patients was seeking care primarily because of a mental health concern.

“These primary care physicians are the gatekeepers,” said study leader Avshalom Caspi, the Edward M. Arnett Professor of Psychology and Neuroscience at Duke University. “The primary care physician data allows us to actually see people at their first contact with the healthcare system.”

Researchers examined more than 350 million primary care visits for 4.8 million people from January 2006 to December 2019, as recorded by the Norwegian government. Each visit’s principal health concern was coded by the physicians, enabling the researchers to take a deep dive into what these doctors are seeing every day. The study appears Sept. 19 Nature Mental Health.

“The idea was basically to see what parts of the body are they treating,” said Caspi, who has co-developed a measure for the pace of a person’s aging process. “It turns out that 12% of all the encounters that primary care physicians have are for mental health problems. So of the 350 million encounters, they have over 40 million mental health encounters.”

The data cover 14 years, ending in 2019 – pre-pandemic – and reflects a purely Norwegian population with socialized health care. Norway is one of the wealthiest nations on Earth, with effectively zero extreme poverty, and ranks seventh on a global measure of happiest countries, while the U.S. isn’t even in the top 20.

But the insight into how much mental health figures into routine primary care is still valuable, Caspi said. “This is the complete record of people aged zero to 100, from all walks of life.”

The prevalence of mental health concerns was about equal to the number coming in for respiratory and cardiovascular complaints, and more than coming in for infections, injuries, digestive, skin, urological or sensory issues.

Caspi said the most important takeaway is that the volume of mental health encounters being seen by primary physicians is second only to aches and pains. While it’s mostly depression or anxiety, they are seeing “diverse and complicated conditions,” including psychosis. “As I look at all this, I'm just staggered by the complexity of the mental health issues primary care physicians are having to contend with.”

Depression, sleep disturbance, stress and anxiety, memory problems and substance abuse led the list. But concerns also included ADHD, learning problems, post-traumatic stress, eating disorders, sexual issues, psychosis and suicidal thoughts.

Caspi adds that it is also important to note “this isn't just happening at one point in the lifespan, it's happening everywhere, among all age groups,” he said. Mental health concerns peaked in the 40s, when 1 out of every 5 visits to a primary-care physician was for a mental health issue.

“A primary care physician, on any given day, is going to encounter mental health issues in pediatric patients, in geriatric patients and among middle aged adults,” Caspi said.

“This report underscores what has become increasingly evident in medicine: without targeted efforts to expand mental health services within the primary care setting, the medical system will not meet the mental health needs of those that it serves,” said Dr. Damon Tweedy, a professor of psychiatry and behavioral sciences at Duke Health, who was not involved in this study.

Post-pandemic, this trend is also unavoidable in pediatric primary care, said Malinda Teague, an assistant clinical professor in the Duke School of Nursing, who was not involved with this study. “Even if it's a regular well-child visit, almost every child is coming in with some concern about behavior, anxiety, depression.”

Caspi stops short of suggesting that primary care physicians need to become more educated in mental health, but he would like to see mental health professionals better integrated into the primary care model. “You go to see your GP and you’ve got a mental health problem. And they say ‘let's go right down the hall and get you set up.’ That’s called a warm handoff, and the VA has been good about that.”

Teague agrees and notes that Duke pediatric primary care already has a similar model, but she says it is not enough. "These embedded mental health clinicians are quickly at capacity and can’t see all the patients that are in need. Primary care providers must be competent and confident in handling common mental health conditions to provide this access to care for their patients."

“The American Academy of Pediatrics made a recommendation a few years ago that every child 12 and up should be screened for depression at every visit,” Teague said. “I can tell you though, that doesn't happen. You've got someone coming in for an ear infection, or coming in for a cough. Who's screening them for depression? Because of our fee-for-service model, the time limits on patient visits don't really support that very well," she said. "As a result, these screenings are only happening at yearly check-ups and we are missing enormous opportunities to help.”

Regardless, Caspi encouraged patients to share their mental health concerns with their doctors. “Don’t be shy,” he said. “Because they are seeing this a lot.”

CITATION: “Nationwide Analysis of 350 million Patient Encounters Reveals a High Volume of Mental-Health Conditions in Primary Care,” Avshalom Caspi, Renata Houts, Terrie Moffitt, Lea Richmond-Rakerd, Matthew Hanna, Hans Fredrik Sunde, Fartein Ask Torvik. Nature Mental Health, Sept. 19, 2024. DOI: 10.1038/s44220-024-00310-5

Journal

Nature Mental Health

DOI

10.1038/s44220-024-00310-5

Method of Research

Observational study

Subject of Research

People

Article Title

Nationwide Analysis of 350 million Patient Encounters Reveals a High Volume of Mental-Health Conditions in Primary Care

Article Publication Date

19-Sep-2024

Searching for a vaccine against an ancient scourge

Syphilis study evaluates Treponema pallidum clinical and genomic diversity for vaccine design

Peer-Reviewed Publication

University of Connecticut

Syphilis cases have surged worldwide, leaving public health officials scrounging for ways to stop the spread. Now, a large, collaborative study of syphilis genetics from four continents has found hints of a possible target for a vaccine.

Syphilis is a sexually transmitted illness that first appeared in Europe about 500 years ago. Its initial symptoms can vary, but the spiral shaped bacterium that causes it can persist in the body for years, often in the central nervous system, and cause birth defects when it infects infants in utero. Syphilis cases decreased in the middle 20th century as easy, effective treatment with injectable penicillin became available, and became uncommon in the 1990s due to changes in sexual behavior in the wake of the HIV epidemic.

But recently, syphilis has made an unwelcome comeback. There were 207,255 cases in the U.S. in 2022 according to the Centers for Disease Control (CDC), more than any time since the 1950s. Babies, some of them stillborn, made up 3,755 of those cases. Other countries worldwide are seeing the same disturbing upward trend.

Stopping syphilis’s spread has become a pressing public health goal. Now, an international collaboration of researchers and doctors has collected one of the most extensive genomic surveys of the syphilis bacterium to date and correlated the genetic data with clinical information about the patients who provided the samples. They are using the data to search for proteins on the surface of the microbe that don’t vary. Such stable proteins could be good targets for a vaccine. They published their findings in the September issue of Lancet Microbe.

Several previous scientific studies using whole genome-sequencing of Treponema pallidum subspecies pallidum (the bacterium that causes syphilis, abbreviated as TPA) have helped researchers begin to understand the global distribution of circulating strains. However, few analyses of specimens for the purpose of evaluating TPA clinical and genetic diversity to inform syphilis vaccine development have been performed.

This study enrolled participants from four countries, including Colombia, China, Malawi, and the U.S. Samples of TPA genomes from Africa and South America had been underrepresented in previous genetic studies and were a particularly valuable addition to the TPA genetic dataset.

Once the samples were collected, they were sent to the University of North Carolina’s Institute for Global Health and Infectious Diseases in Chapel Hill (UNC-Chapel Hill) to have their genetic sequences mapped in Dr. Jonathan Parr’s laboratory.

“Whole-genome sequencing samples collected by partners around the world improved our understanding of circulating Treponema pallidum strains. The results help us understand differences between strains and identify targets for vaccine development,” said Parr.

The researchers’ genetic mapping and protein modeling found that syphilis bacteria differed noticeably between continents, but there were enough similarities that the researchers believe they could find good targets for an effective global vaccine.

UConn School of Medicine Professor Justin Radolf, one of the senior authors on the publication and a Principal Investigator on the NIH U19 award that funded the study, emphasized the importance of these findings.

“By mapping mutations to three-dimensional models of the bacterium’s proteins, we’ve gained crucial insights that will inform the design of a syphilis vaccine,” Radolf said.

Researchers at UNC-Chapel Hill are assessing vaccine acceptability to determine what concerns individuals may have on participating in future syphilis vaccine trials and the potential impact of a vaccine on key populations.

“Engaging with the community now is really important in order to get patients’ opinions and concerns about a future syphilis vaccine trial even before the vaccine has been developed,” said Dr. Arlene C. Seña from UNC-Chapel Hill, co-lead on the clinical study that enrolled participants worldwide and the lead author on the Lancet Microbe manuscript.

The team has already secured funding to continue their efforts to develop a syphilis vaccine.

“This study highlights the power of collaboration,” said Juan Salazar, Physician-in-Chief at Connecticut Children’s and co-lead of the project, who also serves as chair of the department of pediatrics at UConn School of Medicine. "Our work here is not just about addressing a local health concern; it’s about contributing to a global solution for a disease that continues to affect millions worldwide.”

The study was supported by grants from the National Institutes of Health (NIH), the Bill & Melinda Gates Foundation, Connecticut Children’s Medical Center, and several international research institutions.

About Connecticut Children’s

Connecticut Children’s is the only health system in Connecticut 100% dedicated to kids. That means high-quality care across more than 30 pediatric specialties in 40+ locations throughout Connecticut, Eastern New York and Western Massachusetts. One team on a mission to improve access to healthcare from before birth and into adulthood. One team pushing the limits with breakthrough research and community partnerships so we can help you focus on what matters most: your family’s wellness journey. When you choose Connecticut Children’s, you can expect care Beyond Imagination.

About UConn Health

UConn Health is Connecticut’s only public academic medical center with an annual economic impact of $3.3 billion. Based on a 206-acre campus in Farmington, UConn Health has a three-part mission: research, teaching and patient care. Home to the UConn School of Medicine, School of Dental Medicine and UConn John Dempsey Hospital, UConn Health has nearly 5,000 employees supporting more than 1,000 students, over 1.6 million annual patient encounters, and innovative scientific research contributing to the advancement of medicine. It is Connecticut’s No. 1 producer of medical and dental professionals. In fact, UConn is the largest single source of new physicians, surgeons, and dentists for the state, and also is a significant source of trained scientists and public health experts. For more information, visit health.uconn.edu.

About the UNC Institute for Global Health and Infectious Diseases

The UNC Institute for Global Health and Infectious Diseases at the University of North Carolina at Chapel Hill’s School of Medicine is an engine for global health research and pan-university collaboration, transforming health in North Carolina and around the world. Facilitating research excellence for 100+ global health investigators, funded through the National Institutes of Health, the Institute nurtures emerging scientists through training that builds capacity and health security, with service that strives for the highest attainable outcomes in patient care.

Journal

The Lancet Microbe

DOI

10.1016/S2666-5247(24)00087-9

Method of Research

Experimental study

Subject of Research

People

Article Title

Clinical and genomic diversity of Treponema pallidum subspecies pallidum to inform vaccine research: an international, molecular epidemiology study

Unnecessary isolation for mpox may be reduced by adopting testing-based protocols

Nagoya University

mpox, a disease caused by the monkeypox virus, saw a significant increase in cases from mid-2022. The variant in the 2022 outbreak, named clade IIb, spread globally, primarily affecting men who have sex with men. In response, there has been a growing need for effective isolation strategies that balance public health and personal freedom.

Using individual patient data of clade IIb mpox cases, the dominant clade during the 2022 outbreak in Europe and America, a study led by researchers at Nagoya University in Japan has proposed a sophisticated modeling framework to enhance isolation protocols for mpox patients.

Their results show that the current standard practice to end isolation is effective, but implementing testing-based protocols can further reduce unnecessary isolation after the infectious period. Their findings, published in Nature Communications, may improve our response strategies and reduce patient isolation times.

“Our approach emphasizes the critical role of understanding individual variations in viral shedding dynamics to minimize both the risk of prematurely ending isolation and unnecessary prolonged isolation,” said Shingo Iwami. “Based on our results, the use of PCR testing may reduce the burden of isolation on mpox patients while preventing further transmission, especially when the number of mpox patients is increasing.”

The primary method to control the spread of mpox has been to isolate infected individuals. Current recommendations for the isolation of patients with mpox are symptom-based. The average duration of symptoms is about 3 weeks.

However, the infection period of mpox differs among patients. Some health officials are concerned that strategies based on symptoms or fixed time periods may not address this variability. Consequently, individuals being released into the community may still be infectious.

Iwami and his colleagues aimed to refine isolation strategies by developing a modeling framework to characterize when infected individuals cease to be infectious, thus optimizing isolation protocols. They built the models using viral load in lesion samples from previous studies of mpox.

They found that the duration of viral shedding among individuals ranged from 23 to 50 days. The researchers also found greater variation in the duration of viral shedding among mpox cases that spread in Europe and the United States in 2022.

Using these data, the group compared three isolation strategies: a symptom-based rule where isolation ends when symptoms disappear; a fixed-duration rule where isolation ends after a fixed period, typically three weeks; and a testing-based rule where isolation is based on a negative test result with varying numbers and intervals of tests.

Their results showed that the fixed-duration rule provided a balance between the risk and unnecessary isolation but was less flexible. However, the testing-based rule shortened this period, depending on the number of tests and intervals. They concluded that, while the fixed-duration rule was effective, the testing-based approach offered a more tailored solution that could better match the infectious period of individuals.

“The testing-based rule proved effective in minimizing the risk of ending isolation prematurely and reducing unnecessary isolation time,” Iwami said. “According to our analysis, 63% of individuals in the analyzed population could benefit from reduced isolation periods using the testing-based rule compared to symptom-based or fixed-duration rules.”

“To maintain the risk of ending isolation early at below 5%, PCR testing optimized by our simulations could reduce isolation periods by more than a week on average compared to the general isolation rule that is based on the disappearance of symptoms,” he said. "Our simulations showed that if patients are tested at intervals of 2 to 5 days and have three to four consecutive negative results, we can safely end their isolation," he continued. “This underscores the limitations of one-size-fits-all isolation policies.”

Implementing a testing-based rule requires careful planning and resources but could be more effective in managing isolation duration and reducing the burden on isolated individuals. Public health policies could incorporate these insights into designing more flexible and responsive isolation strategies. Using detailed viral load data and sophisticated modeling, public health authorities can develop more effective isolation protocols that minimize both the risk of prematurely ending isolation and unnecessary extended isolation.

Iwami said, “Although our study was based on clade IIb data, if similar data become available for clade Ib, the variant circulating in the current growing epidemic in Africa, we believe the approach of this study would be a useful tool for planning the optimal duration of infection prevention and control.”

Journal

Nature Communications

DOI

10.1038/s41467-024-51143-w

Article Title

Modelling the effectiveness of an isolation strategy for managing mpox outbreaks with variable infectiousness profiles

Breastfeeding is crucial to shaping infant’s microbes and promoting lung health

NYU Langone Health / NYU Grossman School of Medicine

image:
Caption: Electron microscope image of bacteria from an infant’s gut
view more
Credit: Credit: Courtesy of Liat Shenhav, NYU Langone Health

Human breast milk regulates a baby’s mix of microbes, or microbiome, during the infant’s first year of life. This in turn lowers the child’s risk of developing asthma, a new study shows.

Led by researchers at NYU Langone Health and the University of Manitoba, the study results showed that breastfeeding beyond three months supports the gradual maturation of the microbiome in the infant’s digestive system and nasal cavity, the upper part of the respiratory tract. Conversely, stopping breastfeeding earlier than three months disrupts the paced development of the microbiome and was linked to a higher risk of preschool asthma.

Some components in breast milk, such as complex sugars called human milk oligosaccharides, can only be broken down with the help of certain microbes. This provides a competitive advantage to microbes capable of digesting these sugars. By contrast, infants who are weaned earlier than three months from breast milk and who then rely solely on formula feeding, become home to a different set of microbes — ones that will help the infant to digest the components in formula. While many of these microbes that thrive on formula do eventually end up in all babies, the researchers showed that their early arrival is linked to an increased risk of asthma.

“Just as a pacemaker regulates the rhythm of the heart, breastfeeding and human milk set the pace and sequence for microbial colonization in the infant’s gut and nasal cavity, ensuring that this process occurs in an orderly and timely manner,” said study co-senior investigator and computational biologist Liat Shenhav, PhD. “Healthy microbiome development is not only about having the right microbes. They also need to arrive in the right order at the right time,” said Shenhav, an assistant professor at NYU Grossman School of Medicine, its Institute for Systems Genetics, and the School’s Department of Microbiology.

For the study, Shenhav, who is also an assistant professor at NYU’s Courant Institute of Mathematical Sciences, worked in collaboration with study co-senior investigator Meghan Azad, PhD, director of the Manitoba Interdisciplinary Lactation Center, and a professor of pediatrics and child health, at the University of Manitoba.

Another key study finding was that the bacterial species called Ruminococcus gnavus appeared much sooner in the guts of children who were weaned early from breast milk than in those of children who were exclusively breastfed. The bacterium is known to be involved in the production of molecules called short-chain fatty acids, and the formation and breakdown of the amino acid tryptophan. Both tryptophan and its metabolites have been linked to immune system regulation and disruption in previous research, including an increased risk of asthma. The study authors noted that beyond aiding in digestion, an infant’s microbiome plays a crucial role in the immune system’s development.

Publishing in the journal Cell online Sept. 19, the study tracked the ebb and flow of microbes in the guts and noses of infants during the first year of life, as well as details on breastfeeding and the composition of their mothers’ milk. All the children and their mothers were participating in the CHILD Cohort Study, a long-term research project that has been studying the same 3,500 Canadian children at different stages of life from the womb well into adolescence.

The data provided by the CHILD Cohort Study enabled researchers to detangle the impact of breastfeeding on an infant’s microbiome from a range of other environmental factors, including prenatal smoke exposure, antibiotics, and the mother’s asthma history.

Even when these factors were accounted for, they found that breastfeeding duration remained a powerful determinant for the child’s microbial makeup over time. They also used these microbial dynamics and data on milk components to train a machine-learning model that accurately predicted asthma years in advance. Finally, they created a statistical model to learn causal relationships, which showed that the primary way breastfeeding reduces asthma risk is through shaping the infant’s microbiome.

“The algorithms we developed provide valuable insights into microbial dynamics during an infant’s first year of life and how these microbes interacted with the infant,” said Shenhav. “These insights allowed us to move beyond identifying associations, enhancing our ability to make predictions and explore causal relationships.

“Our research highlights the profound impact of breastfeeding on the infant microbiome and breastfeeding’s essential role in supporting respiratory health. By uncovering the mechanisms behind the protective effects of breast milk, as demonstrated in this study, we aim to inform national guidelines on breastfeeding and weaning from breast milk in a data-driven manner.

“With further research, our findings could also contribute to developing strategies to prevent asthma in children who cannot be breastfed for at least three months,” she added.

Funding support for the study was provided by National Institutes of Health grant DP2AI185753. Additional funding was provided by Genome British Columbia (274CHI), the University of British Columbia, CIHR CGS-D, the Canadian Institute for Advanced Research’s Humans and the Microbiome program, and the Canada Research Chair Program. Study participants were all volunteers from families involved in the CHILD Cohort Study, which was initially funded by the Canadian Institute of Health Research (CIHR) and AllerGen NCE.

Besides Shenhav and Azad, other study co-senior investigators are Padmaja Subbarao at the University of Toronto and Michael Surrette at McMaster University in Hamilton.

Other study co-investigators include co-first author Kelsey Fehr and co-author Elinor Simons, both at the University of Manitoba; and co-authors Myrtha Reyna, Ruixue Dai, Theo Moraes, and Vanessa Breton at the University of Toronto; Charisse Petersen, Darlene Dai, and Stuart Turvey at the University of British Columbia; Laura Rossi and Marek Smieja at McMaster University; Michael A. Silverman and Maayan Levy at the University of Pennsylvania in Philadelphia; Lars Bode at the University of California, San Diego; Catherine Field and Piush Mandhane at the University of Alberta; and Jean S. Marshall from Dalhousie University in Halifax.

Media Inquiries:

David March

212-404-3528

david.march@nyulangone.org

STUDY DOI

10.1016/j.cell.2024.07.022

STUDY LINK WILL BECOME ACTIVE AFTER EMBARGO LIFTS

https://cell.com/cell/fulltext/S0092-8674(24)00782-7

AN IMAGE IS ALSO AVAILABLE UPON REQUEST

Caption: Electron microscope image of bacteria from an infant’s gut

Credit: Courtesy of Liat Shenhav, NYU Langone Health

Journal

Cell

DOI

10.1016/j.cell.2024.07.022

Method of Research

Randomized controlled/clinical trial

Subject of Research

People

Article Title

Microbial colonization programs are structured by breastfeeding and guide healthy respiratory development

Article Publication Date

19-Sep-2024

COI Statement

New organic thermoelectric device that can harvest energy at room temperature

Researchers have succeeded in developing a framework for organic thermoelectric power generation from ambient temperature and without a temperature gradient

Kyushu University

Illustration of the organic thermoelectric device — image:
This new organic thermoelectric device can convert room temperature heat, which is abundant in living environments and was previously not considered a possible energy source, into usable electrical energy. As no temperature gradient is required, meaning no cooling unit is required, the device can be made compact.
view more
Credit: Kyushu University/Chihaya Adachi

Fukuoka, Japan—Researchers have developed a new organic thermoelectric device that can harvest energy from ambient temperature. While thermoelectric devices have several uses today, hurdles still exist to their full utilization. By combining the unique abilities of organic materials, the team succeeded in developing a framework for thermoelectric power generation at room temperature without any temperature gradient. Their findings were published in the journal Nature Communications.

Thermoelectric devices, or thermoelectric generators, are a series of energy-generating materials that can convert heat into electricity so long as there is a temperature gradient—where one side of the device is hot and the other side is cool. Such devices have been a significant focus of research and development for their potential utility in harvesting waste heat from other energy-generating methods.

Perhaps the most well-known use of thermoelectric generators is in space probes such as the Mars Curiosity rover or the Voyager probe. These machines are powered by radioisotope thermoelectric generators, where the heat generated from radioactive isotopes provides the temperature gradient for the thermoelectric devices to power their instruments. However, due to issues including high production cost, use of hazardous materials, low energy efficiency, and the necessity of relatively high temperatures, thermoelectric devices remain underutilized today.

“We were investigating ways to make a thermoelectric device that could harvest energy from ambient temperature. Our lab focuses on the utility and application of organic compounds, and many organic compounds have unique properties where they can easily transfer energy between each other.” explains Professor Chihaya Adachi of Kyushu University’s Center for Organic Photonics and Electronics Research (OPERA) who led the study. “A good example of the power of organic compounds can be found in OLEDs or organic solar cells.”

The key was to find compounds that work well as charge transfer interfaces, meaning that they can easily transfer electrons between each other. After testing various materials, the team found two viable compounds: copper phthalocyanine (CuPc) and copper hexadecafluoro phthalocyanine (F16CuPc).

“To improve the thermoelectric property of this new interface, we also incorporated fullerenes and BCP,” continues Adachi. “These are known to be good facilitators of electron transport. Adding these compounds together significantly enhanced the device’s power. In the end, we had an optimized device with a 180 nm layer of CuPc, 320 nm of F16CuPc, 20 nm of fullerene, and 20 nm of BCP.”

The optimized device had an open-circuit voltage of 384 mV, a short-circuit current density of 1.1 μA/cm2, and a maximum output of 94 nW/cm2. Moreover, all these results were achieved at room temperature without the use of a temperature gradient.

“There have been considerable advances in the development of thermoelectric devices, and our new proposed organic device will certainly help move things forward,” concludes Adachi. “We would like to continue working on this new device and see if we can optimize it further with different materials. We can even likely achieve a higher current density if we increase the device’s area, which is unusual even for organic materials. It just goes to show that organic materials hold amazing potential.”

###

For more information about this research, see “Organic Thermoelectric Device Utilizing Charge Transfer Interface as the Charge Generation by Harvesting Thermal Energy," Shun Kondo, Mana Kameyama, Kentaro Imaoka, Yoko Shimoi, Fabrice Mathevet, Takashi Fujihara, Hiroshi Goto, Hajime Nakanotani, Masayuki Yahiro, and Chihaya Adachi, Nature Communications, https://doi.org/10.1038/s41467-024-52047-5

About Kyushu University
Founded in 1911, Kyushu University is one of Japan's leading research-oriented institutes of higher education, consistently ranking as one of the top ten Japanese universities in the Times Higher Education World University Rankings and the QS World Rankings. The university is one of the seven national universities in Japan, located in Fukuoka, on the island of Kyushu—the most southwestern of Japan’s four main islands with a population and land size slightly larger than Belgium. Kyushu U’s multiple campuses—home to around 19,000 students and 8000 faculty and staff—are located around Fukuoka City, a coastal metropolis that is frequently ranked among the world's most livable cities and historically known as Japan's gateway to Asia. Through its VISION 2030, Kyushu U will “drive social change with integrative knowledge.” By fusing the spectrum of knowledge, from the humanities and arts to engineering and medical sciences, Kyushu U will strengthen its research in the key areas of decarbonization, medicine and health, and environment and food, to tackle society’s most pressing issues.

Journal

Nature Communications

DOI

10.1038/s41467-024-52047-5

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Organic Thermoelectric Device Utilizing Charge Transfer Interface as the Charge Generation by Harvesting Thermal Energy

Low-carbon ammonia offers green alternative for agriculture and hydrogen transport

RMIT University

Low-carbon ammonia researcher — image:
Dr Karma Zuraiqi from RMIT University holds a vial of copper, a key component of the team’s new catalyst.
view more
Credit: Michael Quin, RMIT

A new way of making ammonia by harnessing the unique power of liquid metal could lead to significant cuts in carbon emissions caused by production of the widely-used chemical.

Ammonia is used in fertiliser to grow much of our food, but also plays a role in clean energy as a carrier to safely transport hydrogen.

The global production of ammonia, however, comes at a high environmental cost: it consumes over 2% of global energy and produces up to 2% of global carbon emissions.

RMIT Research Fellow and study lead author, Dr Karma Zuraiqi, said their greener alternative used 20% less heat and 98% less pressure than the century-old Haber-Bosch process used today for splitting nitrogen and hydrogen into ammonia.

“Ammonia production worldwide is currently responsible for twice the emissions of Australia. If we can improve this process and make it less energy intensive, we can make a large dent in carbon emissions,” said Zuraiqi, from the School of Engineering.

Results of the RMIT-led study published in Nature Catalysis show their low-energy approach to be as effective at producing ammonia as the current gold standard by relying more on effective liquid metal catalysts and less on the force of pressure.

“The copper and gallium we use is also much cheaper and more abundant than the precious metal ruthenium used as a catalyst in current approaches,” Zuraiqi said. “These advantages all make it an exciting new development that we’re keen to take further and test outside the lab.”

Liquid metal to the rescue

The team including RMIT’s Professor Torben Daeneke is at the forefront of harnessing the special properties of liquid metal catalysts for ammonia production, carbon capture and energy production.

A catalyst is a substance that makes chemical reactions occur faster and more easily without itself being consumed.

This latest study showcased their new technique by creating tiny liquid metal droplets containing copper and gallium – named ‘nano planets’ for their hard crust, liquid outer core and solid inner core structure – as the catalyst to break apart the raw ingredients of nitrogen and hydrogen.

“Liquid metals allow us to move the chemical elements around in a more dynamic way that gets everything to the interface and enables more efficient reactions, ideal for catalysis,” Daeneke said.

“Copper and gallium separately had both been discounted as famously bad catalysts for ammonia production, yet together they do the job extremely well.”

Tests revealed gallium broke apart the nitrogen, while the presence of copper helped the splitting of hydrogen, combining to work as effectively as current approaches at a fraction of the cost.

“We essentially found a way to take advantage of the synergy between the two metals, lifting their individual activity,” Daeneke said.

RMIT is now leading commercialisation of the technology, which is co-owned by RMIT and QUT.

Upscaling for industry

While ammonia produced via the traditional Haber-Bosch process is only viable at huge facilities, the team’s alternative approach could suit both large-scale and smaller, decentralised production, where small amounts are made cheaply at solar farms, which in turn would slash transport costs and emissions.

As well as obvious applications in producing ammonia for fertiliser, the technology could be a key enabler for the hydrogen industry and support the move away from fossil fuels.

“One good way to make hydrogen safer and easier to transport is to turn it into ammonia,” Daeneke explained.

“But if we use ammonia produced through current techniques as a hydrogen carrier, then emissions from the hydrogen industry could significantly increase global emissions.”

“Our vision is to combine our green ammonia production technology with hydrogen technologies allowing green energy to be shipped safely around the world without huge losses on the way,” he said.

The next challenges are to upscale the technology – which has so far been proven in lab conditions – and to design the system to operate at even lower pressures, making it more practical as a decentralised tool for a broader range of industries.

“At this stage, we are really excited by the results and are keen to speak with potential partners interested in scaling this up for their industry,” he said.

This research was supported by the Australian Research Council and the Australian Synchrotron (ANSTO). Analysis of molecular interactions was carried out at RMIT’s cutting-edge Microscopy and Microanalysis Facility, as well as QUT’s Central Analytical Research Facility, the Australian Synchrotron and via the NCI Australia supercomputing facility.

‘Unveiling metal mobility in liquid metal catalysts for ammonia synthesis’ is published in Nature Catalysis (DOI: 10.1038/s41929-024-01219-z).

Once the paper has been published online, it will be available at the following URL: https://www.nature.com/articles/s41929-024-01219-z

Authors are Karma Zuraiqi (RMIT), Yichao Jin (QUT) Caiden Parker (RMIT), Jaydon Meilak (Swinburne), Nastaran Meftahi (RMIT, Exciton Science), Andrew Christofferson (RMIT, Exciton Science), Salvy Russo (RMIT, Exciton Science), Michelle Spencer (RMIT, FLEET), Huai Yong Zhu (QUT), Lizhuo Wang (University of Sydney), Jun Huang (University of Sydney), Rosalie Hocking (Swinburne), Ken Chiang (RMIT), Sarina Sarina (QUT) and Torben Daeneke (RMIT).

MULTIMEDIA FOR MEDIA USE

Photos related to this story are available for download at this link: https://spaces.hightail.com/space/IwparT2Is3

Suggested captions:

Group photo
Dr Ken Chiang, Dr Karma Zuraiqi and Professor Torben Daeneke. Credit: Michael Quin, RMIT

Liquid metal

A new way of making ammonia by harnessing the unique power of liquid metal could lead to significant cuts in carbon emissions caused by production of the widely-used chemical. Credit: Michael Quin, RMIT

Profile photo

Dr Karma Zuraiqi holds a vial of copper, a key component of the team’s new catalyst. Credit: Michael Quin, RMIT

Journal

Nature Catalysis

DOI

10.1038/s41929-024-01219-z

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Unveiling metal mobility in a liquid Cu–Ga catalyst for ammonia synthesis

Article Publication Date

19-Sep-2024