Pnas Science Sessions

How much carbon dioxide concrete can absorb Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Hessam Azarijafari explains the extent to which concrete can absorb carbon dioxide over its lifecycle. In this episode, we cover: •[00:00] Introduction. •[00:56] Construction engineer Hessam Azarijafari introduces us to the recipe for concrete. •[01:41] He explains how concrete absorbs carbon dioxide throughout its lifespan, and why this absorption is important. •[02:52] Azarijafari talks about the background of the study. •[03:45] He describes the model built for the study and the data source. •[05:59] Azarijafari tells the study's results, including variation in absorpti

Determining how well extinct animals could smell Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Quentin Martinez describes a reconstruction of olfactory capabilities in extinct mammals. In this episode, we cover: •[00:00] Introduction •[01:14] Evolutionary biologist Quentin Martinez tell why we want to reconstruct olfaction in extinct animals. •[02:35] He introduces the olfactory bulb endocast, or space within the skull that contained the olfactory bulb, and explains why it's important in evaluating olfaction in extinct animals. •[04:24] Martinez talks about studying the genomics of chemoreceptor genes, in addition to the bony structure of the olfactory bulb end

Hidden sustainability costs of AI Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers describe the sustainability impact of AI data centers. In this episode, we cover: •[00:00] Introduction •[01:20] Bronis de Supinski describes how the energy demands of AI data centers have increased in recent years and why improvements in data center energy efficiency will not necessarily reduce total energy expenditures •[03:08] Eric Masanet explains the difficulty of tracking and projecting the energy usage of AI data centers. •[05:12] Shaolei Ren describes the water usage and air pollution associated with AI data centers. •[07:30] Tevfik Kosar explains how AI might be

Molecular regulation of mosquito biting timing Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Laura Duvall introduces a potential pathway for disrupting the biting behavior of mosquitoes. In this episode, we cover: •[00:00] Introduction •[00:57] Mosquito neuroscientist Laura Duvall introduces us to the normal biting behavior of mosquitoes. •[02:46] She tells why the biting behavior of the Aedes aegypti mosquito is of particular interest. •[03:24] Duvall describes findings regarding how mosquitoes' responses to CO2 vary over times of day. •[05:37] She introduces the PDF peptide that might be regulating timing of biting behavior and explains how losing that peptid

How well flu vaccines protect public health Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Lauren Meyers explains what the 2022-2023 influenza season taught us about the effectiveness of flu vaccines. In this episode, we cover: •[00:00] Introduction •[01:16] Computational epidemiologist Lauren Meyers introduces the health and hospitalization burden of seasonal influenza. •[01:47] She defines vaccine effectiveness. •[02:37] Meyers describes the features of the 2022-2023 flu season. •[04:05] She describes how the researchers estimated the hospitalizations prevented by vaccination. •[05:11] Meyers tells how vaccination of young adults protected adults over 65 years

Air quality and pet health Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Sarah Shackleton shares climate lessons learned from 6 million-year-old ice. In this episode, we cover: •[00:00] Introduction •[01:02] Paleoclimate and ice scientist Sarah Shackleton introduces the information researchers can glean from ice cores. •[02:02] She recounts the age extent of previous ice cores. •[03:03] Shackleton describes the Allan Hills Ice Area. •[04:35] She describes the method for ascertaining the age of air in an ice core. •[05:49] She explains the results of the study and the insights into the climate in Antarctica over the last 6 million years. •[06:32] Shackleton talk

China's science leadership Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, James Evans explains how and why China's leadership in global science is rising. In this episode, we cover: •[00:00] Introduction •[00:56] Social and complex systems scientist James Evans recounts the recent history of the trajectories of science in the U.S. and in China. •[01:50] He explains how to measure a country's scientific leadership and introduces the data sources used in the study. •[04:18] Evans tells the results of the study, and talks about some areas of science in which China's leadership has particularly advanced. •[06:20] He lists the key takeaways from the study for policym

Genetic history of dog domestication Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers explore the impact of domestication on dog genetics and behavior. In this episode, we cover: •[00:00] Introduction •[01:00] Greger Larson explains how the history of gene flow between dogs and their wild relatives differs from what we know about other domestic species. •[02:38] Audrey Lin finds that low levels of wolf ancestry are found in almost two thirds of dog breeds. •[04:18] Linus Girdland Flink documents evidence of two genetic wolves on a remote Scandinavian island that may have been under human control. •[06:13] Clément Car explores how the mating systems of

Air quality and pet health Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Stephen Jarvis explores the health impacts of poor air quality on pets. In this episode, we cover: •[00:00] Introduction •[00:51] Environmental economist Stephen Jarvis explains how he became interested in the effects of air quality on pets. •[01:59] He talks about the similarities in exposure between humans and pets, and introduces the veterinary dataset used in the study. •[03:30] Jarvis explains the results of the study and the potential physiological effects of poor air quality. •[05:40] He talks about the implications of reducing air pollution for petcare and the takeaway messages of

A giant virus associated with oyster aquaculture mortality Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Curtis Suttle and Kevin Xu Zhong explain how a previously unidentified virus may be connected to mass die-offs of farmed Pacific oysters. In this episode, we cover: • [00:00] Introduction • [01:03] Environmental virologist Curtis Suttle introduces the importance of the Pacific oyster to aquaculture. • [01:42] Suttle describes mass mortality events, including one he witnessed. • [02:42] Environmental microbiologist Kevin Xu Zhong talks about the methods used to identify the Pacific Oyster Nidovirus 1. • [03:53] Zhong describes the notable features of the nido

Swamp lights and bat sight Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers explore two spooky mysteries: the source of will-o'-the-wisps and how bats integrate vision with echolocation. In this episode, we cover: •[00:00] Introduction •[00:58] Richard Zare's background and expertise. •[01:26] Richard, have you ever seen will-o'-the-wisps in the wild? •[01:31] What did we already know about will-o'-the-wisps before your study? •[02:42] How could water droplets ignite methane? •[03:24] Tell us about the methods of your study. How did you explore this phenomenon? •[04:17] What are the broader implications of your findings, beyond just will-o'-the-wisps?

Implications of a mutation in modern humans Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Xiangchun Ju and Svante Pääbo explore the evolutionary implications of a mutation that separates modern humans from ancestral hominins. In this episode, we cover: •[00:00]  •[01:22] Neurobiologist Xiangchun Ju introduces the enzyme adenylosuccinate lyase, or ADSL, and its role in the synthesis of purine. •[02:09] Evolutionary anthropologist Svante Pääbo talks about the discovery of the A429V mutation, which is present in modern humans but not Neanderthals or Denisovans. •[03:38] Ju and Pääbo talk about the methods to humanize mice in order to study the evolutionary importa

Where primates evolved Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Jorge Avaria-Llautureo and Chris Venditti explain why the evolution of primates likely occurred in cold, dry climates rather than in tropical forests. In this episode, we cover: •[00:00] Introduction •[00:58] Evolutionary biologist Jorge Avaria-Lautureo explains the prevailing hypothesis that primates evolved in a tropical climate •[02:54] Evolutionary biologist Chris Venditti introduces evidence suggesting a different origin climate. •[03:54] Avaria discusses how the researchers reconstructed the climate of early primate species. •[05:05] Venditti and Avaria explain why it was important to us

Climate change and lake oxygenation Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Joachim Jansen explains how climate change altered cycles of oxygenation in lakes. In this episode, we cover: •[00:00] Introduction. •[00:56] Limnologist Joachim Jansen introduces us to the cycles of oxygenation in lakes throughout the seasons. •[02:35] He describes previous hypothesis about climate change and lake oxygenation and introduces the methods and datasets of the study.  •[04:59] Jansen introduces the results of the study, including key differences between large and small lakes. •[06:54] He talks about the consequences of deoxygenation.  •[09:03] Jansen explains the cave

The physics of the squash nick shot Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Roberto Zenit explains the physics behind the unanswerable nick shot in the game of squash. In this episode, we cover: •[00:00] Introduction. •[00:56] Engineer Roberto Zenit introduces the game of squash, including his participation in the sport, and introduces the nick shot. •[02:11] He talks about the background and methods of the study.  •[04:50] Zenit describes the mechanics of a nick shot. •[06:01] He talks about the implications of the study for squash players and for other applications. •[08:52] Zenit recounts the caveats and limitations of the study. •[09:41] Conclusion. A

A pterosaur and its ecosystem at the end of the Triassic Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Kay Behrensmeyer and Ben Kligman describe what a fossil bone bed in Arizona reveals about a 209-million-year-old pterosaur and its ecosystem. In this episode, we cover: •[00:00] Introduction •[01:01] Paleoecologist Kay Behrensmeyer and paleontologist Ben Kligman describe the discovery of this fossil bone bed. •[03:10] Kligman and Behrensmeyer introduce a previously undescribed pterosaur. •[05:00] They talk about what this specimen says about the ecology and evolution of pterosaurs. •[06:15] Kligman and Behrensmeyer talk about the importance of studying this fo

The postglacial history of the Saimaa ringed seal Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Jaakko Pohjoismäki, Jukka Jernvall, and Ari Löytynoja discuss the evolutionary history of the Saimaa ringed seal. In this episode, we cover: •[00:00] Introduction •[01:06] Molecular biologist Jaakko Pohjoismäki introduces Lake Saimaa and the Saimaa ringed seal. •[02:30] Zoologist Jukka Jernvall talks about the characteristics of species isolated by glaciation. •[03:27] Evolutionary biologist and bioinformatician Ari Löytynoja explains the genetic and demographic methods of the study. •[04:11] Löytynoja and Jernvall explain why the results were surprising and where th

Managing eastern black rhinoceros populations with genetic studies Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Barbara Mable and Ronald Mellya show how allowing endangered rhinos to move between populations enhances genetic diversity. In this episode, we cover: •[00:00] Introduction •[01:00] Evolutionary geneticist Barbara Mable explains why is genetic diversity important in managing small, isolated populations of rhinos. •[02:59] Park warden Ronald Mellya describes how his firsthand experience with rhino management led to this study. •[04:52] Mable explains the methods of the study and the contributions of co-author Anubhab Khan. •[06:20] Mable talks about

A reference genome aids efforts to rescue the northern white rhinoceros Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Franz-Josef Müller explains genomic tools to aid the functionally extinct northern white rhinoceros. In this episode, we cover: •[00:00] Introduction •[01:11] Multidisciplinary scientist Franz-Josef Müller introduces the northern white rhinoceros. •[01:55] He introduces induced pluripotent stem cells and why they’re important in efforts to save the northern white rhinoceros. •[04:20] He talks about the genomic risks of using induced pluripotent stem cells •[05:21] Müller tells the story of how he and his colleagues came together to complete the

Water and the possibility of life on Mars Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers explain what we know about the potential for water and life on Mars and what we might learn from analysis of returned samples. In this episode, we cover: •[00:00] Introduction •[01:04] Mark Thiemens explains the importance of bringing samples from Mars back to Earth. •[02:37] Arya Udry explains the current gaps and limitations in the geological record provided by Martian meteorites. •[03:55] Bruce Jakosky explains what we currently know about the presence and history of water on Mars. •[05:26] Monica Grady explains how analyzing volatile species in Martian sample