It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, December 17, 2025
NAU team releases 13 years of detailed U.S. CO2 emissions data
New research from Northern Arizona University shows detailed CO2 emissions for the United States from 2010 to 2022.
In the first of a series of data releases, professor Kevin Gurney of NAU’s School of Informatics, Computing, and Cyber Systems (SICCS) authored a study, published today in Scientific Data, that includes a database of 13 years of carbon dioxide emissions in the United States. Future releases will include neighborhood- and city-specific emissions, road segment vehicular emissions and industrial facility emissions.
“The U.S. taxpayers have a right to this data,” said Gurney, who specializes in atmospheric science, ecology and public policy and has spent the past two decades developing a standardized system quantifying greenhouse gas emissions. “In spite of the science funding cuts and threats to federal science data reporting, my team will continue to produce and share data critical to climate change and environmental quality. With the proposed rule to end the United States Environmental Protection Agency greenhouse gas reporting program, this data is more important than ever.”
The goal of providing the CO2 emissions data is to give businesses, cities and communities greater insight into their emissions, driving well-informed environmental policy choices grounded in the best data.
Gurney and his team have been developing the granular maps of CO2 emissions for two decades and the latest release is version four of the Vulcan system. Vulcan reflects every source of CO2 emissions from the combustion of coal, oil and natural gas in the United States, targeted to the time and location where fuel is burned.
“The output constitutes many terabytes of data and requires a high-performance computing system to run,” said Pawlok Dass, a research associate in SICCS and co-investigator in the study. “It captures CO2 emissions at unprecedented resolution—down to every city block, road segment and individual factory or powerplant.”
In The New York Times’ “Lost Science” series, Gurney acknowledged that funding cuts have had an impact on the ability to innovate and move quickly but is resolute in ensuring that the CO2 emissions data gets to the public.
“We all remain committed to this research,” said Bilal Aslam, a Ph.D. student working on the emissions study. “Rather than ignoring or suppressing this type of climate data, policymakers should seize the opportunity to create trading markets and climate-friendly investments. We can both limit climate change and have economic growth.”
Gurney’s Vulcan and Hestia projects, both funded by multiple federal agencies, quantify and visualize greenhouse gases emitted across the entire country down to individual power plants, neighborhoods and roadways, identifying problem areas and enabling better decisions about where to cut emissions most effectively. His estimates have shown excellent performance when compared to direct atmospheric monitoring. Gurney has authored more than 180 scientific publications, including a recent U.S. National Academy Report, “Greenhouse Gas Emissions for Decision making.” He has been involved with the United Nations Climate Change Framework Convention and the Kyoto Protocol for more than 25 years and is a lead author for the Intergovernmental Panel on Climate Change (IPCC).
Journal
Scientific Data
Subject of Research
Not applicable
Article Publication Date
17-Dec-2025
Unveiling how sodium-ion batteries can charge faster than lithium-ion ones
Detailed experimental analysis reveals the decisive mechanisms governing ion kinetics at hard carbon negative electrodes
These images depict electrodes with different ratios of hard carbon (red) to Al2O3 (green), the latter of which is electrochemically inert. Using the more diluted versions of the electrode, certain rate-limiting phenomena can be avoided, enabling scientists to more accurately measure ion kinetics in hard carbon.
Credit: Professor Shinichi Komaba from Tokyo University of Science, Japan
The worldwide push for sustainability requires better, more durable batteries to support renewable energy systems and our ubiquitous electronic devices. While lithium-ion batteries (LIBs) are currently the go-to solution, future calls for alternatives built on materials more widely available than lithium. Because sodium is abundant and available at low-cost, sodium-ion batteries (SIBs) are a leading candidate for replacing LIBs while still meeting global energy demands.
The key to SIBs’ remarkable performance lies partly in the material used at the negative electrode called hard carbon (HC). This low crystalline, porous type of carbon can store large amounts of sodium, enabling SIBs to reach energy densities comparable to commercial LIBs. Though scientists believe that HC is a fast-charging material, proving this experimentally is challenging. The problem is that conventional battery testing often underestimates the material’s true charging rate due to issues with concentration overvoltage in composite electrode. Simply put, during rapid charging, the dense composite structure of the electrode can cause ‘ion traffic jams,’ where ion transport in the electrolyte limits the reaction speed. Thus, the fundamental charging rate limit of HC, as well as how the rate of sodium insertion compares to lithium, remain unclear.
To address this knowledge gap, a research team led by Professor Shinichi Komaba, alongside a third-year PhD candidate Mr. Yuki Fujii and Assistant Professor Zachary T. Gossage from the Department of Applied Chemistry, Tokyo University of Science, Japan, employed an innovative approach to uncover the kinetic limits of sodium and lithium insertion into HC. Their work was published in the journal Chemical Science on December 17, 2025.
The researchers used a technique known as the ‘diluted electrode method.’*1 It involves creating an electrode that combines both HC particles and an electrochemically inactive material like aluminum oxide. At the appropriate ratio, it ensures that each HC particle is surrounded by an ample supply of ions, eliminating the typical ion transport issues within the electrolyte and at the negative electrode. Using this approach, the researchers were able to very effectively measure and compare the maximum rates for sodiation (sodium insertion), lithium intercalation, and lithiation (lithium insertion) into HC. Furthermore, sodiation into diluted HC electrode showed comparable rate capability to lithium intercalation at diluted graphite electrodes.
Our results provided clear and quantitative evidence of HC’s high-rate potential. Through detailed testing and analysis using cyclic voltammetry, electrochemical impedance spectrometry, and potential-step chronoamperometry, the team found that the sodiation process is intrinsically faster than lithiation for the same negative electrode. This was confirmed by calculating the apparent diffusion coefficient—a measure of how quickly ions move through the material—which was generally higher for sodium than for lithium. “Our results quantitatively demonstrate that the charging speed of an SIB using an HC anode can attain faster rates than that of an LIB,” highlights Prof. Komaba.
Furthermore, the team precisely identified that the rate-determining step for the entire charging process is the pore-filling mechanism, which occurs when ions aggregate to form pseudo-metallic clusters within HC’s nanopores. While the initial stage of charging (adsorption/intercalation) was found to be very fast for both ions, the speed of the total reaction is ultimately limited by the efficiency of the pore-filling process. Detailed chemical kinetic analysis revealed that sodium requires less energy than lithium to form these clusters, which helps explain the rate advantages observed. By identifying this bottleneck, this study provides a clear direction for faster and more energy-efficient battery designs. “A key point of focus for developing improved HC materials for fast-chargeable SIBs is to attain faster kinetics of the pore-filling process so that they can be accessed at high charging rates. Also, our results suggest that sodium insertion is less sensitive to temperature, based on the consideration of smaller activation energy than lithiation, ” explains Prof. Komaba.
The findings of this work tell us that SIBs are not simply a cheaper and safer alternative to LIBs, but that they offer genuine performance advantages in charging speed, which are especially relevant in high-power applications. Additionally, SIBs could offer more stable operation than LIBs. Further studies to perfect SIBs will slowly but surely pave the way for new battery technologies, supporting current endeavors to build sustainable societies.
* 1 Diluted electrode method This unique and effective electrochemical method for evaluating kinetics of insertion materials was originally developed by Associate Professor Kingo Ariyoshi from Osaka Metropolitan University. In this research, the negative electrode active material, i.e. HC powder, was partially replaced by aluminum oxide powder, which is electrochemically inactive.
About Tokyo University of Science Tokyo University of Science (TUS) is a well-known and respected university, and the largest science-specialized private research university in Japan, with four campuses in central Tokyo and its suburbs and in Hokkaido. Established in 1881, the university has continually contributed to Japan's development in science by fostering a love for science among researchers, technicians, and educators.
With a mission of “Creating science and technology for the harmonious development of nature, human beings, and society," TUS has undertaken a wide range of research from basic to applied science. TUS has embraced a multidisciplinary approach to research and undertaken intensive study in some of today's most vital fields. TUS is a meritocracy where the best in science is recognized and nurtured. It is the only private university in Japan that has produced a Nobel Prize winner and the only private university in Asia to produce Nobel Prize winners within the natural sciences field.
About Professor Shinichi Komaba from Tokyo University of Science Dr. Shinichi Komaba is currently a Professor in the Department of Applied Chemistry at Tokyo University of Science (TUS). He obtained his Ph.D. from Waseda University in Japan. At TUS, he leads a team of over 30 undergraduate, master’s, and Ph.D. students, as well as post-docs and Assistant Professors, focusing on the development of next-generation energy-storage materials. He has published over 470 articles, accumulating over 40,000 citations. His research is centered around sodium-ion batteries, with a broader focus on functional solid-state chemistry, inorganic industrial materials, and electrochemistry. He has received multiple awards for his scientific contributions, including the “2025 Highly Cited Researchers” and “IBA2025 Research Award,” which has been published as hot news of the year.
Funding information This study was partially funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Program: Data Creation and Utilization Type Materials Research. (JPMXP1122712807), the JST through CREST (Grant No. JPMJCR21O6), ASPIRE (JPMJAP2313), and GteX (JPMJGX23S4), and JSPS-Grant-in-Aid for JSPS Fellows (24KJ2024).
The findings show that short-duration, light exercises can significantly improve inhibitory control and elevate mood in children, offering valuable insights for practical interventions.
In modern society, physical inactivity and sedentary behavior have become common issues globally. This trend is also growing among children, raising concerns for their mental and physical health. Sedentary behavior in children can affect the development of executive function (EF), higher-order cognitive processes that govern goal-oriented behavior and self-control, necessary for daily life. Strong EF during childhood forms the foundation for self-regulation and social functioning, academic achievement, and emotional well-being throughout childhood and adolescence.
Previous studies have shown that both acute and chronic exercises can enhance EF. While chronic exercise is essential for long-term cognitive development, even brief bouts of activity can offer immediate, but short-lived, cognitive and emotional benefits that may help improve children’s learning efficiency during the school day. Other studies have also highlighted the importance of short-duration exercise interventions, such as light-intensity exercise, that can be delivered within the classroom. While many studies show that light-intensity exercise improves inhibitory control (a core component of EF) and mood in adults, very few studies have examined whether these same benefits occur in children.
In a new study, a research team led by doctoral student Takashi Naito from the Graduate School of Sport Sciences at Waseda University in Japan investigated whether brief, light-intensity exercise improves EF and psychological mood in children. “Studies have shown that more than 80% of children worldwide do not meet WHO’s recommended level of physical activity, and their sedentary time has increased by about 1 hour per day over the last decade,” says Naito, explaining their motivation. The team also included Professor Kaori Ishii and Professor Koichiro Oka from Waseda University. Their study was published in Volume 15 of the Scientific Reports on December 05, 2025.
Thirty-one healthy school children, aged 10-14 years, participated in the study. Researchers ensured that none had a history of mental or neurological disorders, physician-imposed exercise restrictions, or color vision deficiency.
The participants were randomly assigned to either a control group or an exercise group. During the experiment, all participants completed a psychological mood questionnaire followed by a cognitive task twice, before and after a break session. The psychological mood questionnaire was based on the Two-Dimensional Mood Scale, which measures pleasure and arousal scores. For the cognitive task, the well-known Color-word Stroop task (CWST) was administered, which measures inhibitory control ¾ defined as the ability to control attention, thoughts, and emotions to override internal impulses or external distractions and instead carry out a more appropriate or required action.
During the break session, the participants in the control group rested for 15 minutes. Those in the experiment group rested for 10 minutes, then engaged in a light 3.5-minute exercise, followed by an additional 1.5-minute rest. The exercise program comprised six easy-to-perform movements, including dynamic stretching, static stretching with trunk rotation, single-leg balance, and hand dexterity exercises, all associated with prefrontal cortex (PFC) activation. The researchers also conducted heart-rate measurements during the exercise for the experiment group and examined PFC activation during CWST for both groups.
Children who performed the light-intensity exercise showed significantly reduced reaction times in the following cognitive task compared to the control group. “Our findings show that incorporating short bouts of light-intensity exercise in school, such as before the beginning of classes or during breaks, can improve inhibitory control and mood in children, with potential to improve learning efficiency,” remarks Naito.
Importantly, this is the first study worldwide across all age groups to demonstrate improvements in both executive function and mood using light-intensity exercise, lasting less than 5 minutes.
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Reference Authors: Takashi Naito1,2, Koichiro Oka3, and Kaori Ishii3 DOI: https://doi.org/10.1038/s41598-025-27358-2 Affiliations: 1Graduate School of Sport Sciences, Waseda University 2Organization for the Strategic Coordination of Research and Intellectual Properties, Meiji University 3Faculty of Sport Sciences, Waseda University
About Waseda University Located in the heart of Tokyo, Waseda University is a leading private research university that has long been dedicated to academic excellence, innovative research, and civic engagement at both the local and global levels since 1882. The University has produced many changemakers in its history, including eight prime ministers and many leaders in business, science and technology, literature, sports, and film. Waseda has strong collaborations with overseas research institutions and is committed to advancing cutting-edge research and developing leaders who can contribute to the resolution of complex, global social issues. The University has set a target of achieving a zero-carbon campus by 2032, in line with the Sustainable Development Goals (SDGs) adopted by the United Nations in 2015. To learn more about Waseda University, visit https://www.waseda.jp/top/en
About Takashi Naito Takashi Naito is a doctoral student at the Graduate School of Sport Sciences, Waseda University. He holds a master’s degree in Sport Sciences from Waseda University with a focus on physical activity, sedentary behavior, exercise science, and cognitive function.He also serves as a part-time lecturer at Rikkyo University, Surugadai University, and Showa Medical University. Naito has received awards for his research and has published extensively on exercise and cognitive health, including studies on light-intensity exercise and its impact on children.
Funding Information This study was supported by JSPS (Japan Society for the Promotion of Science) KAKENHI (Grant numbers: JP 21K11507 [Takashi Naito], JP 23K10770 [Kaori Ishii and Koichiro Oka]).
