Humans make lots of irrational decisions in predictable ways,but what if we’re all just doing our best within the limits of our abilities?Researchers were able to simulate human behaviors using aprobabilistic finite automaton,a well-known model of limited computational power.They programmed the automatons to compete against each other in awildlife poaching game,as either arhino poacher or aranger trying to stop the poaching.When the automatons could remember everything,they settled into an optimal game strategy.But when researchers limited their memories,they took some decision-making shortcuts–the same kinds as actual humans playing the game.This new work supports the idea of bounded rationality,that“sometimes we do silly things or make systemic mistakes,not because we’re irrational but because we have limited resources,”said first author Xinming Liu’20.“Oftentimes,we cannot remember everything that happened in the past or we don’t have enough time to make afully rational decision.”Liu presented the work,“Strategic Play By Resource-Bounded Agents in Security Games,”in May at the 2023 International Conference on Autonomous Agents and Multiagent Systems.The senior author is Joseph Halpern,professor of computer science in the Cornell Ann S.Bowers College of Computing and Information Science.In the poaching game,there are ahandful of sites,each with adifferent probability of containing arhino.In each round,the poacher and ranger choose asite to visit,making their decisions based on data from previous rounds.The poacher gains points by catching arhino;the ranger gains points by catching the poacher.If the poacher and ranger can recall every move in the game,they soon settle into Nash equilibrium–a rational,unchanging pair of strategies.But if the automatons have more limited memory–so they can’t remember where they saw that rhino 10,100 or 1,000 rounds back–they make seemingly irrational human-like decisions.One human behavior the automatons emulated was probability matching.This occurs when aperson is guessing the results of acoin toss when the coin is weighted to be heads three out of four times.Instead of always guessing heads,which would give a75%success rate,many people would guess heads three-quarters of the time,which would lower their success rate to about 63%.In the game,this means the poacher made more visits to sites where they most often encountered rhinos in the past,and fewer visits to sites that rarely had arhino.For the automatons,this strategy wasn’t ideal,but still yielded decent results.Another irrational human behavior that led to good game performance was overweighting significant results–a phenomenon in which important or traumatic incidents loom especially large in the memory.For example,a person might drive slowly down astretch of road where they received aspeeding ticket many years ago.When the researchers programmed the poachers to overweight previous encounters with the ranger,it paid off in the game.They ended up avoiding sites where the rangers were most likely to be.To see how these results match up to actual humans,Liu recruited approximately 100 people to play as the poacher on an online platform.While some humans chose the same site every time or picked randomly just to finish the game and receive payment,others chose sites purely based on probability matching.A third group assumed the ranger was probability matching,and visited sites accordingly to avoid the ranger.The similarities in gameplay between the humans and automatons show that the model can re-create at least two human behaviors,which,instead of being irrational,actually improved their performance.“Another way to interpret it is to say that you’re doing the best you can given your computational limitations,”Halpern said.“And that strikes me as pretty rational.” 查看详细>>

Cornell scientists have revealed anew phase of matter in candidate topological superconductors that could have significant consequences for condensed matter physics and for the field of quantum computing and spintronics.Researchers at the Macroscopic Quantum Matter Group at Cornell have discovered and visualized acrystalline yet superconducting state in anew and unusual superconductor,Uranium Ditelluride(UTe2),using one of the world’s most powerful millikelvin Scanned Josephson Tunnelling Microscopes(SJTM).This“spin-triplet electron-pair crystal”is apreviously unknown state of topological quantum matter.The findings,“Detection of aPair Density Wave State in UTe2,”were published June 28 in Nature.Qiangqiang Gu,a postdoctoral researcher working in the lab of physicist J.C.Séamus Davis,the James Gilbert White Distinguished Professor Emeritus in the College of Arts and Sciences,co-led the research with Joe Carroll of University College Cork and Shuqiu Wang of Oxford University.Superconductors are topological when the pairing potential exhibits odd parity,leading to each electron pair adopting aspin-triplet state,with both electron spins oriented in the same direction.Topological superconductors are the target of intense research by physicists because they can,in theory,form the materials platform for ultra-stable quantum computers,said Gu.However,even after adecade of intense investigation into topological superconductivity,no bulk materials have been definitively recognized as spin-triplet,odd-parity superconductors,with the exception of superfluid 3He,which was also discovered at Cornell.Recently,the exotic new material Uranium Ditelluride(UTe2)has emerged as ahighly promising candidate for this classification.However,its superconductive order parameter remains elusive,said Gu.In 2021,theoretical physicists began to propose that UTe2 is actually in atopological pair-density-wave(PDW)state.No such form of quantum matter had ever been detected.In simple terms,a PDW is like astationary dance of the paired electrons found in asuperconductor,but the pairs form periodic crystalline patterns in space.“Our team at Cornell discovered the first PDW ever observed in 2016 using the superconductive-tip Scanned Josephson Tunnelling Microscope that we invented for that purpose,”said Gu.“Since then,we have pioneered SJTM studies at millikelvin temperatures and with microvolt energy resolution.For the UTe2 project,we have directly visualized the spatial modulations of the superconducting pairing potential at atomic scale and found them to modulate exactly as predicted in aPDW state as the density of electron pairs modulates periodically in space.What we detected is anew quantum matter state–a topological pair density wave composed of spin-triplet Cooper pairs.”Cooper-pair density waves are aform of electronic quantum matter in which pairs of electrons freeze into asuperconductive PDW state,instead of forming aconventional“superconductive”fluid where all are in the same freely moving state.“The discovery of the first PDW in spin-triplet superconductors is exciting,”said Gu.“Uranium-based heavy fermion superconducting compounds are anew and exotic class of materials that provide apromising platform for realisation of topological superconductivity.…Our scientific discovery also points out the ubiquitous nature of this intriguing quantum state in s-wave,d-wave and p-wave superconductors,and it sheds light on new avenues for identifying such states in abroad spectrum of materials.” 查看详细>>

Zoonotic spillover—when diseases pass between animals and humans—is amajor cause of disease and the primary cause of recent pandemics,including COVID-19.Scientists and practitioners from four continents will gather for awebinar that explores how strategic protection and restoration of natural habitats could disrupt pathways to zoonotic spillover,while also addressing climate change and biodiversity loss.The webinar,“How to Prevent the Next Pandemic:Nature-Based Solutions and Policy Opportunities,”will be Monday,June 26 at 11 a.m.,and hosted by Raina Plowright,a Cornell Atkinson Scholar and the Rudolf J.and Katharine L.Steffen Professor of Veterinary Medicine in the Department of Public and Ecosystem Health.It will be moderated by award-winning science writer David Quammen,with an opening statement by Maria Van Kerkhove’99,head of the Emerging Diseases and Zoonoses Unit for the World Health Organization(WHO)and technical lead for WHO’s COVID-19 response.“Almost every scenario of zoonotic spillover involves some kind of land-use change,but if you look at the pandemic treaties being negotiated right now,they do not include preventative solutions,”Plowright said.“Current pandemic treaties are focused on what happens once we have apathogen running rampant within the human population,but there’s little investment in that upstream process:identifying critical pinch points in nature and how to intervene so we can prevent spillover from happening in the first place.”Plowright advocates for carefully constructed ecological countermeasures:actions that protect and restore wildlife habitat or mitigate wildlife-human interactions.Such countermeasures act as a“critical first line of defense”against pandemics,while providing many co-benefits,including reducing the impacts of climate change and enhancing biodiversity,she said.Panelists are 10 global and cross-disciplinary experts,who will examine the fundamental drivers of pandemics,the strategies we can take to prevent them,and the current policy opportunities for primary pandemic prevention. 查看详细>>

A new study led by Weill Cornell Medicine and NewYork-Presbyterian investigators has found that the risk of long COVID and its symptoms present very differently across diverse populations and suggests that further investigation is needed to accurately define the disease and improve diagnosis and treatment.The study,published April 7in Nature Communications,analyzed electronic health records as part of the National Institutes of Health’s Researching COVID to Enhance Recovery(RECOVER)Initiative to better understand the persistence of symptoms after SARS-CoV-2 infection,also known as long COVID,among broad,diverse populations.Led by Dr.Rainu Kaushal,chair of the Department of Population Health Sciences at Weill Cornell Medicine and physician-in-chief of population health sciences at NewYork-Presbyterian Hospital/Weill Cornell Medical Center,the research provides an overview of potential symptoms after acute COVID-19 and how the risk of these conditions may vary among different populations in the United States.“Long COVID is anew disease that is very complicated and quite difficult to characterize,”said Chengxi Zang,an instructor in population health sciences at Weill Cornell Medicine and lead author on the paper.“It affects multiple organs and presents asevere burden to society,making it urgent that we define this disease and determine how well that definition applies among different populations.This paper provides the basis for furthering research on long COVID.”The team studied electronic health records from two clinical research networks that are part of the National Patient-Centered Clinical Research Network(PCORnet).One dataset,from the INSIGHT Clinical Research Network–which Kaushal leads–included data from 11 million New York-based patients,while the other came from the OneFlorida+network,which included 16.8 million patients from Florida,Georgia and Alabama.The team identified abroad list of diagnoses that occurred more frequently in patients who had recently had COVID compared with non-infected individuals.The researchers also found more types of symptoms and higher risk of long COVID in New York City than Florida.Specific conditions found across the New York City and Florida populations included dementia,hair loss,sores in the stomach and small intestine,blood clots in the lung,chest pain,abnormal heartbeat and fatigue.“Our approach,which involves using machine learning with electronic health records,provides adata-driven way to define long COVID and determine how generalizable our definition of the disease is,”Zang said.Comparing records across diverse populations in regionsthat experienced the COVID-19 pandemic differently highlighted how variable long COVID is for patients and emphasized the need for further investigation to improve the diagnosis and treatment of the disease.Some of the differences between the results from the two populations might be explained by the fact that New York City had amore diverse patient population,endured one of the first waves of the pandemic and faced the lack of personal protective equipment such as masks,compared with Florida,Zang said.The new study is related to previous work by Kaushal,who is also senior associate dean for clinical research and the Nanette Laitman Distinguished Professor of Population Health Sciences at Weill Cornell Medicine,and colleagues,that categorized different subtypes of long COVID.“In this new research,we examined abroad list of potential long COVID conditions one by one,”said Fei Wang,associate professor of population health sciences and co-senior author of the study.“These findings can help us better recognize the broad involvement of multiple organ systems in long COVID,and design appropriate plans for patient management and treatment development.”Many Weill Cornell Medicine physicians and scientists maintain relationships and collaborate with external organizations to foster scientific innovation and provide expert guidance.The institution makes these disclosures public to ensure transparency.For this information,see profiles for Dr.Fei Wang and Dr.Rainu Kaushal. 查看详细>>

Cornell researchers have unearthed precise,microscopic clues to where magma is stored,offering scientists–and government officials in populated areas–a way to better assess the risk of volcanic eruptions.The new research was published Feb.8 in Science Advances.In recent years,scientists have used satellite imagery,earthquake data and GPS to search for ground deformation near active volcanoes,but those techniques can be inaccurate in locating the depth of magma storage.By finding microscopic,carbon dioxide-rich fluids encased in cooled volcanic crystals,scientists can determine accurately,within one hundred meters,where magma is located.“A fundamental question is where magma is stored in Earth’s crust and mantle,”said lead author Esteban Gazel,the Charles N.Mellowes Professor in Engineering,in Cornell Engineering.“That location matters because you can gauge the risk of an eruption by pinpointing the specific location of magma,instead of other signals like hydrothermal system of avolcano.”Gazel said speed and precision are essential.“We’re demonstrating the enormous potential of this improved technique in terms of its rapidity and unprecedented accuracy,”he said.“We can produce data within days of the samples arriving from asite,which provides better,near real-time results.”In volcanic events,magma reaches the Earth’s surface and it erupts as lava and–depending on how much gas it contains–it could be explosive in nature.When deposited as part of the fallout of the eruption,fragmented fine-grained material–called tephra–can be collected and quickly evaluated.Gazel and doctoral student Kyle Dayton,the first author of the paper,“Deep Magma Storage During the 2021 La Palma Eruption,”deduced how to use inclusions of carbon dioxide-rich fluids trapped within olivine crystals to precisely indicate depth,as the carbon dioxide density of these inclusions is controlled by pressure.These fluids can be measured quickly using acalibrated Raman spectroscopy instrument to determine–in terms of kilometers–how far down the magma was stored and the depth of the scorching reservoir.More precise Raman spectroscopy methods were developed in the Gazel lab.“We improved the precision by an order of magnitude from available geobarometers,from kilometers to meters,”he said,“but also the spatial resolution of inclusion measurements from tens of microns,down to one micron compared to previously available microthermometry techniques.”After five decades of dormancy,new vents in the Cumbre Vieja volcano on La Palma in the Canary Islands opened and began erupting Sept.19,2021.Weeks later,Gazel and Dayton joined asmall,elite team of international researchers to study the volcano.This Canary Islands research led to Gazel and Dayton to pick through tephra to find crystals,which in turn provide data to improve eruption models and forecasts.“We’re finding how deep magma is stored before an eruption through what the volcano brings up,”Dayton said.“As these volcanic crystals grow,they occasionally,accidentally trap little bubbles of carbon dioxide fluid,”she said.“These crystals get exhumed during the volcanic eruption and we search the tephra and look for crystals containing fluid inclusions.Through these tiny accidents we can uncover some of Earth’s volcanic secrets from the deep to better understand and prepare for future eruptions.”The co-authors are:Penny Wieser,University of California,Berkeley;Valentin R.Troll and Frances M.Deegan,Uppsala University,Sweden;Juan Carlos Carracedo and Francisco J.Perez-Torrado,University of Las Palmas de Gran Canaria,Spain;Hector La Madrid,University of Missouri;Diana C.Roman,Carnegie Institution for Science,Washington;Jamison Ward,University of Minnesota;Meritxell Aulinas and Guillem Gisbert,Universitat de Barcelona,Spain;and Harri Geiger,University of Freiburg,Germany.The research was funded by the National Science Foundation and aNASA Interdisciplinary Science grant. 查看详细>>

Credit:NASA The Additive Vehicle-Embedded Cooling Technologies project at Cornell is being funded by NASA to advance the future of space exploration,including nuclear power-enabled missions.Around Cornell News directly from Cornell‘s colleges and centers Researchers explore nuclear power cooling with NASA grant.By Syl Kacapyr.January 6,2023 As space exploration becomes more ambitious,Cornell Engineeri... 查看详细>>

A typical gut bacterium that can spread through the body and cause aserious infection resists natural immune defenses and antibiotics by enhancing its protective outer layer,known as the cell envelope,according to anew study by Weill Cornell Medicine investigators.The finding suggests possible new ways to target these bacterial infections.The research,published Nov.10 in mBio,illuminates some of the underlying changes that may occur when Enterococcus faecalis(E.faecalis)populations move through the epithelial cells lining of the intestine and escape to reach other body sites.“Systemic infections with E.faecalis can be lethal because this microbe has aremarkable ability to adapt to various environments and resist treatments,”said principal investigator Diana K.Morales,assistant professor of microbiology and immunology in obstetrics and gynecology at Weill Cornell Medicine.People at risk of developing these infections include those who are taking antibiotics or who have compromised immune systems,which facilitate E.faecalis overgrowth in the intestine.Understanding how E.faecalis moves out of the gut and spreads may one day help scientists find small molecules to stop the bacterium’s extra-intestinal dissemination,preventing dangerous infections.How the bacterium can move out of the intestine and to other organs has remained largely unexplored.However,researchers have observed that two different populations of the same species of bacterium exist,Morales said.One population develops traits that allow it to pass through the intestinal barrier acquiring an advantageous resistance to antimicrobials,while the other stays put.In aseries of previous laboratory studies of the bacterium,the researchers found that motile E.faecalis produces molecules formed by sugar chains called polysaccharides that allow the bacterium to aggregate or clump together.“When these bacteria aggregate,they seem to develop an ability to move,”Morales said.In the current study,the investigators,including lead author Yusibeska Ramos,a research associate in Obstetrics and Gynecology,found that the motile form of E.faecalis has acell envelope containing increased amounts of glycolipids,which are fat molecules linked with acarbohydrate.Enhanced production of cell envelope glycolipids appears to help the bacterium to resist extracellular stressors.These stressors include the antimicrobial agent daptomycin,a common treatment for E.faecalis infection,andβ-defensins,small molecules intestinal epithelial cells produce to deter infection.The researchers also found that genetic mutations that inhibit glycolipid production made E.faecalis more sensitive to these stressors and reduced the ability of the bacterium to penetrate cell surfaces and move through intestinal epithelial cells.The next step for the researchers is to evaluate additional in vivo models to confirm whether the molecular pathways uncovered in the current study are needed for the bacterium to exit the intestine.“We are also interested in identifying pharmacological approaches that can target these specific pathways with the goal of one day helping patients better fight infections by this gut microbe,”Morales said. 查看详细>>

Weill Cornell Medicine has been awarded a$9.8 million grant from the National Institutes of Health to lead aconsortium of health care institutions that are analyzing nationwide health data in an effort to unravel the complexities of long COVID.“We need it to be able to answer important questions about this new condition,”said principal investigator Dr.Rainu Kaushal,senior associate dean for clinical research and chair of population health sciences at Weill Cornell Medicine and physician-in-chief of population health sciences at NewYork-Presbyterian/Weill Cornell Medical Center.“The goal is to characterize post-acute COVID and determine who is at risk,”Kaushal said.“Who gets it?What is the life course?What treatments prevent it or ameliorate symptoms?It’s important that we advance our understanding so patients with post-acute COVID can be recognized and treated.”The one-year NIH award is part of afederal initiative called Researching COVID to Enhance Recovery(RECOVER),a national effort to define,treat and prevent the long-term effects of COVID-19.NYU Langone Health is leading the RECOVER Clinical Science Core,through which multidisciplinary collaborative investigator groups,such as the one led by Kaushal,are conducting their research.In patients with long COVID–or post-acute sequelae of SARS-CoV-2 infection(PASC),as it’s known in the medical community–symptoms such as“brain fog,”sleep disturbances,fevers and gastrointestinal problems can persist for weeks or months after infection.Current data suggests that 10%to 30%of patients diagnosed with COVID-19 will experience long COVID,but the biological factors that underlie the condition are unclear.To better understand why some patients recover from COVID-19 infection while others have persistent symptoms,investigators will tap into data collected by the National Patient-Centered Clinical Research Network(PCORnet),which comprises eight consortiums of health care institutions from around the country;Kaushal leads the New York-based INSIGHT Clinical Research Network.Through its members,PCORnet has amassed deidentified records from more than amillion patients nationwide who have had laboratory-confirmed COVID-19 infections.This database will continue to expand as more patient information is collected monthly.With Weill Cornell Medicine as the study hub,RECOVER investigators from 41 peer institutions will use this patient information to better understand long COVID in adults.The data,in conjunction with findings from more than 200 published studies and clinical observations stemming from physicians actively treating patients,will support investigator-led efforts to develop algorithms to identify COVID patients with PASC and determine who is most at risk for developing the condition.Investigators will also use the data to examine disparities between different demographic populations and discern COVID-19 vaccines’effects on PASC development.A parallel research effort,coordinated by Children’s Hospital of Philadelphia,will focus on health data from children who’ve had COVID-19 and developed the rare but serious condition known as multisystem inflammatory syndrome in children(MIS-C),which is aform of long COVID.“At this level and scope,this is very much groundbreaking,”Kaushal said.“I applaud the NIH’s commitment to utilizing health data science and big data to drive rapid,meaningful insights into disease characterizations.”Theresa Juva is afreelance writer for Weill Cornell Medicine. 查看详细>>

Cornell Engineering assistant professors Peter McMahon,Francesco Monticone and Atieh Moridi are among the 32 researchers selected from more than 220 applicants to receive Office of Naval Research(ONR)Young Investigator Program(YIP)awards,which support early-career scientists and engineers.The Young Investigator Program is ahighly competitive early-career award program recognizing prior academic achievement and potential for significant scientific breakthrough.College and university tenure-track faculty who earned aPh.D.on or after Jan.1,2014,were eligible for YIP awards this year.McMahon,from the School of Applied and Engineering Physics,researches the physics of computation and how physical systems can be engineered to perform computation in new ways.His YIP application,“Superconducting Electronics Neural Networks for Wideband RF Signal Processing,”was awarded in the program area of Cryogenically Enabled Electronics Technologies for Mixed Signal Systems. 查看详细>>

New Cornell research shows how to make offshore wind farms more efficient in the face of impending rapid expansion–crucial information as the U.S.Department of the Interior affirmed White House plans to lease federal waters for several giant arrays of wind turbines along the waters of the East Coast.This research appears in the Oct.20 issue of the journal Joule.“Massive upscaling of wind turbine deployments offshore is critical to achieving global and national goals to decarbonize the electricity supply,”said Sara C.Pryor,professor of Earth and Atmospheric Sciences,a department shared by the College of Agricultural and Life Sciences,and the College of Engineering.“The excellent wind resource and proximity to large markets along the East Coast means it is the focus of America’s first-phase,offshore-wind projects,where thousands of physically larger and higher capacity wind turbines will be deployed over large areas(about 1.7 million acres of water,combined)at an unprecedented scale,”Pryor said.On Oct.13,Secretary of the Interior Deb Haaland announced the path forward for offshore wind leasing agreements to meet the White House-announced goal to deploy 30 gigawatts–enough to power 90 million homes–of East Coast offshore wind energy by 2030.At the New York State level,there are now five offshore wind projects in active development,according to the New York State Energy Research and Development Authority(NYSERDA).The state has an offshore goal of 9,000 megawatts by 2035.The current offshore projects total about 4,300 megawatts,enough to power approximately 2million homes.While the approaching federal rapid expansion of offshore turbine deployments brings achance to reduce human-induced climate change,Pryor said,it presents challenges on how to optimally locate offshore turbines to efficiently achieve electricity-generation goals.Low-turbulence conditions over water,plus the locations and size of the lease areas auctioned by the Interior Department’s Bureau of Ocean Energy Management,mean that individual wind farms will experience each other’s wake(disturbed air flow)–even when the turbine arrays are 15 to 50 miles apart.Thus,the wind turbines may fatigue earlier and agroup of turbines may experience up to 30%lower power production due to wake effects,according to the new paper.Pryor’s simulations can help to optimize turbine spacing in these areas and assist plans for future deployments.Industry trends are moving toward large wind turbines deployed over bigger areas.In Europe,as an example,wind farms have increased in capacity from 321 megawatts to 621 megawatts between 2010 and 2019.The Hornsea Project,a recent project off the eastern coast of the United Kingdom,comprises many more wind turbines and can produce 1.2 gigawatts of electrical power. 查看详细>>