Marissa Weichman,an assistant professor in the Department of Chemistry,has been awarded a2023 Packard Fellowship for Science and Engineering by the David and Lucile Packard Foundation for her proposal to study atmospheric aerosols and their potential role in climate change.Weichman is one of 20 scientists nationwide to receive the prestigious,early-career fellowship,among the nation’s largest nongovernmental awards.Designed to allow maximum flexibility in the use of award funds,the Foundation allots$875,000 over five years to each fellow to spend on research as they wish.Fellowships are awarded to encourage innovative,blue-sky thinking that could one day foster discoveries to improve lives and broaden our understanding of the universe.Weichman,a physical chemist,was selected for her proposal“The Stratosphere in Focus:New Spectroscopic Tools for Aerosol Science.”“I’m especially thrilled with this fellowship to get to join the community that comes with being aPackard Fellow—all people who are doing such exciting things in their fields across scientific boundaries,”said Weichman.“I’m excited to meet my cohort of fellows on the tenure track,so it really is about finding peers and forming those bonds that are so inspiring.“The Foundation gives you the startup money without restrictions,recognizing that maybe you’ll have other great ideas or there’s something else that you think of tomorrow that you might want to do,”Weichman added.“So for the next five years,that flexibility allows me to go for bigger,riskier ideas that can have greater impact.”Paul Chirik,Princeton’s Edwards S.Sanford Professor of Chemistry and the chair of the department,said:“This highly competitive award speaks to what we all know at Princeton:that Marissa is asuperb scientist,teacher and colleague.Just afew years into her independent career,she has developed an impactful and visible program on light-matter interactions.As aformer Packard fellow,I know these awards allow for the freedom to explore new,high-risk,high-reward ideas outside the realm of traditional funding streams.I have no doubt Marissa will make the most of this opportunity.”Weichman plans to use spectroscopic techniques to investigate uncertainties around the role of aerosols in the atmosphere and their involvement in climate change.Aerosols are ubiquitous,micro-sized particles suspended in the air—such as water droplets,dust and soot—that influence two phenomena central to the Earth’s climate and weather:the scattering of sunlight and the seeding of clouds.These roles,however,are poorly understood.Weichman will look at how aparticle’s size and composition influences its chemistry,the scattering and absorption of light,and its ability to seed cloud droplets.“Aerosol-light and aerosol-cloud interactions remain the largest sources of uncertainty in our best models of Earth’s radiative balance.Our current knowledge of these intricate systems is not sufficient to capture their role in the climate crisis,much less predict the impact of potential climate interventions,”said Weichman.“All of these complicated interactions depend on the size of the particle and its composition.If you’re measuring how these particles behave and averaging over millions of particles of various sizes and compositions,you’ll never be able to understand what’s actually happening.“So instead,we’re going to look at asingle particle.Let’s hold one single salt particle or dust particle,trap it with electromagnetic fields and hold it in place for minutes or hours or days,and watch what happens under abattery of simulated atmospheric conditions.”Weichman believes the data gathered in her lab will provide astrong foundation for decisions about solar radiation management strategies and other efforts to counteract global warming.The daughter and granddaughter of physicists,Weichman was born in California and raised in California,Colorado,and Massachusetts.She also has family roots in the Princeton area.She joined Princeton chemistry in 2020 from the University of Colorado-Boulder,where she was apostdoctoral fellow.She received her B.S.in chemistry from the California Institute of Technology and her Ph.D.in chemistry from the University of California-Berkeley. 查看详细>>

Kocher,an assistant professor of ecology and evolutionary biology and the Lewis-Sigler Institute for Integrative Genomics,is investigating what shapes variation in social behavior.Her lab has developed new tools to study social behavior across different scales,from the molecular building blocks of the“social brain”to the ecological and evolutionary forces that shape social evolution.Her research focuses on aunique group of bees that includes solitary,social,and socially flexible lineages.In these bees,social behavior has been independently gained and lost multiple times,creating an ideal framework for uncovering the factors shaping social behavior and its evolution.After completing her B.S.as one of the first graduates of the Integrative Biology program at the University of Illinois Urbana-Champaign,Kocher went on to study the genetic and physiological underpinnings of queen-worker interactions in honey bees at North Carolina State University,where she completed her Ph.D.in 2009.At Princeton,her lab group combines genetic studies with field work and laboratory observations to understand the wide variations in insects’social behavior.By weaving together genetics,genomics,observations and experiments,her team is able to identify both the key molecular mechanisms underlying these behavioral variations and the environmental factors that influence them.Among Kocher’s other major awards are a2022 Pew Scholarship in the Biomedical Sciences from the Pew Charitable Trusts,a 2021 Packard Fellowship for Science and Engineering from the David and Lucile Packard Foundation,and a2019 New Innovator Award from the National Institutes of Health.“Each of our Freeman Hrabowski Scholars has demonstrated their unique potential to advance cutting-edge science and carve out pathways for the inclusive development of postdocs,students,and other researchers,”said HHMI Vice President and Chief Scientific Officer Leslie Vosshall.“We are thrilled to welcome this inaugural cohort to HHMI,and we are proud to support each Scholar’s contributions to the broader scientific community in the years to come.”Freeman Hrabowski Scholars will be appointed to afive-year term,renewable for asecond five-year term after asuccessful progress evaluation.Each scholar will receive up to$8.6 million over 10 years,including full salary,benefits,a research budget and scientific equipment.In addition,they will participate in professional development to advance their leadership and mentorship skills.HHMI anticipates that the scholars will work toward becoming leaders in their field and believes that,by fostering equitable and inclusive environments in their labs,these scholars will provide astrong foundation for their trainees’future success in science.“The Freeman Hrabowski Scholars program reflects HHMI’s continued commitment to supporting people,not projects,”said HHMI President Erin O’Shea.“We aim to provide Scholars with the resources they need to pursue scientific breakthroughs and empower others to ask critical research questions.In this way,our Scholars are well positioned to make an indelible impact on the future of science.”The Freeman Hrabowski Scholars Program represents akey component of HHMI’s diversity,equity and inclusion commitment.Over the next 20 years,HHMI expects to hire and support up to 150 Freeman Hrabowski Scholars—appointing roughly 30 every other year for the next 10 years.The Institute has committed up to$1.5 billion for the Freeman Hrabowski Scholars to be selected over the next decade.HHMI named the program in honor of Freeman A.Hrabowski III,President Emeritus of the University of Maryland,Baltimore County,and amajor force in increasing the number of scientists,engineers and physicians from backgrounds underrepresented in science in the U.S.HHMI announced the launch of the Freeman Hrabowski Scholars program in May 2022. 查看详细>>

One of the essential factors the COVID-19 virus needs to enter ahost is areceptor on ahuman cell—a place where the universally recognized spike protein can latch onto the cell surface,pierce it,disgorge its infectious contents,and replicate.Without areceptor,there is no replication.Without replication,there is no infection.Researchers in Princeton University’s Department of Chemistry and the Department of Molecular Biology have used acellular mapping technology calledµMap,introduced just two years ago by the MacMillan Lab,to uncover eight previously unknown entry points of interest for the spike protein.Four of them,researchers found,are functionally important for viral entry.The research was published earlier this month in the Journal of the American Chemical Society(JACS).It could expand the suite of tools used to fight the virus,particularly as it mutates and evolves ways to evade vaccines.The collaborative project was begun at the height of pandemic uncertainty two years ago under Alexander Ploss,a leading virologist and professor of molecular biology,and David MacMillan,the James S.McDonnell Distinguished University Professor and aNobel laureate in chemistry.Scientists have known since the SARS-CoV-1 virus appeared in 2003 that its primary viral entry receptor was an enzyme called angiotensin-converting enzyme 2,or ACE2.This enzyme was confirmed in 2020 as the same receptor for SARS-CoV-2,the virus that causes COVID-19.But the Princeton project started with the assumption that ACE2 was not the only story.“We did know that there are certain host molecules that this virus absolutely depends on to enter into lung cells to cause the infection,and one of these molecules is called ACE2,”said Ploss.“So we basically said,okay,let’s see if there’s more out there.We looked for immediate binders.“But as you can imagine,the entry process is complex.The virus attaches to something and then it still has to pass through the cell membrane to get into acell,and along this way it may interact with other host factors.I don’t want to say everything is dictated by viral entry.Obviously,there are anumber of equally essential processes within the cell after the virus has entered that can influence disease severity.“But it’s obviously the first key step.If the virus can’t get in,it’s game over.”Steve Knutson,a co-author on the paper and apostdoctoral research fellow in the MacMillan Lab,added:“While the discovery of ACE2 as the major receptor was ahuge milestone,it certainly doesn’t tell the whole story of COVID pathology.Biology can be inherently promiscuous,and we guessed correctly that the SARS-CoV-2 spike protein interacts with multiple host cell proteins for entry.”He added that investigations like this one are a“perfect”research fit for theµMap technology. 查看详细>>

The ability to edit the genome by altering the DNA sequence inside aliving cell is powerful for research and holds enormous promise for the treatment of diseases.However,existing genome editing technologies frequently result in unwanted mutations or can fail to introduce any changes at all.These problems have kept the field from reaching its full potential.Now,research from the laboratory of Princeton’s Britt Adamson,conducted together with collaborators led by Jonathan Weissman at MIT and Editas Medicine,details anovel method called Repair-seq that reveals how genome editing tools work.“We’ve known for along time that the mechanisms involved in fixing broken DNA are essential for genome editing because to change the sequence of DNA you first have to break it,”said Adamson,senior author on the study and assistant professor in the Princeton Department of Molecular Biology.“But those processes are incredibly complex and thus often difficult to untangle.”To repair DNA,cells use many different mechanisms,each involving several genes working together in distinct pathways.Repair-seq allows researchers to probe the contribution of each of these pathways to DNA repair by profiling how observed mutations change when one of these factors is removed--and to do this for hundreds of genes simultaneously.This lets scientists ask basic questions about DNA repair biology,and investigate how DNA repair mechanisms impact genome editing technologies.Adamson and colleagues first applied their method to one of the most commonly used genome editing approaches,which employs the bacterial Cas9 nuclease to cut across both strands of the double-stranded DNA molecule,creating lesions called double-strand breaks.“Editing with double-strand breaks has been the bread and butter of genome editing for along time,but making intended changes without unwanted mutations has been an enormous challenge.We set out to understand the mechanisms behind as many of these mutation events as possible,figuring that this could help us optimize the system,”Adamson said.Led by first author Jeff Hussmann,a postdoctoral researcher in the laboratory of Jonathan Weissman,the team used the data from Repair-seq to map how different DNA repair pathways are linked to particular types of Cas9-induced mutations.Hussmann’s analysis detected pathways that were already known as well as new ones involved in the repair of double-strand breaks.It also highlighted the enormous complexity and myriad systems involved in double-strand break repair.The deep set of data unearthed in this work is now posted on an online portal that others can use to interrogate DNA repair pathways or proteins.Coincidentally,while these initial studies were being completed,a team led by David Liu at the Broad Institute of MIT and Harvard was developing agenome editing system called“prime editing”that doesn’t rely on creating double-strand breaks.Prime editing typically has alow success rate,but Adamson and Hussmann reasoned that studying the DNA repair pathways involved in prime editing might help identify avenues for improvement,so they joined forces with Liu to investigate prime editing using Repair-seq.“Working together was ahuge benefit,”said Adamson.“For us,it was afantastic experience of collaborative and team-oriented science.”The collaborating researchers found that the ability to obtain intended edits with prime editing was affected by proteins in one repair pathway:the DNA mismatch repair pathway.They then showed that inhibiting or evading that pathway dramatically enhanced the efficiency and accuracy of prime editing outcomes—positioning prime editing to become apreeminent genome editing technology.Importantly,this work also demonstrates how Repair-seq can be used to improve other genome-editing technologies.Further demonstrating Repair-seq’s utility,the collaborating researchers also applied it to athird genome editing system technology,also developed by Liu.Results from that study were recently published in Nature Biotechnology. 查看详细>>

With amassive,nationwide effort the United States could reach net-zero emissions of greenhouse gases by 2050 using existing technology and at costs aligned with historical spending on energy,according to astudy led by Princeton University researchers.The new“Net-Zero America”research outlines five distinct technological pathways for the United States to decarbonize its entire economy.The research is the first study to quantify and map with this degree of specificity,the infrastructure that needs to be built and the investment required to run the country without emitting more greenhouse gases into the atmosphere than are removed from it each year.It’s also the first to pinpoint how jobs and health will be affected in each state at ahighly granular level,sometimes down to the county.The study’s five scenarios describe at ahighly detailed,state-by-state level the scale and pace of technology and capital mobilization needed across the country,and highlight the implications for land use,incumbent energy industries,employment,and health.Initial results were released December 15,in recognition of the urgency to cut greenhouse gas emissions and the need for immediate federal,state,and local policy making efforts.Journal publications will follow in early 2021. 查看详细>>

The funding will support work on ahigh-throughput system to explore how protein interactions give rise to health and disease,a new type of laser that promotes speedier communications and brighter screen displays,and anovel method for harvesting water from air that could transform the habitability and productivity of arid regions.The goal of the fund is to enable researchers to make leaps rather than incremental advances in the natural sciences and engineering.The fund focuses on projects that lead either to the invention of adisruptive new technology that can have amajor impact on afield of research,or on the development of equipment or an enabling technology that will transform research in afield.Eric Schmidt,former CEO of Google,and his wife,Wendy,a businesswoman and philanthropist,created the fund in 2009.Schmidt earned his bachelor’s degree in electrical engineering from Princeton in 1976 and served as aPrinceton trustee from 2004 to 2008.“These projects have the potential to make revolutionary advances through new tools or technologies that transform how researchers pursue answers to today’s challenges,”said Dean for Research Pablo Debenedetti,the Class of 1950 Professor in Engineering and Applied Science,and aprofessor of chemical and biological engineering.“The projects selected for funding this year are emblematic of Princeton’s dedication to innovative research that leads eventually to benefits for society.”The winning proposals were selected by acommittee of peers.The three winning technologies are highlighted below.The group photos were taken before social distancing protocols were implemented to limit the spread of the coronavirus. 查看详细>>

Until now,this has been the situation for the bits of hardware that make up asilicon quantum computer,a type of quantum computer with the potential to be cheaper and more versatile than today’s versions.Now ateam based at Princeton University has overcome this limitation and demonstrated that two quantum-computing components,known as silicon“spin”qubits,can interact even when spaced relatively far apart on acomputer chip.The study was published in the journal Nature.silicon-spin quantum bit Researchers at Princeton University have made an important step forward in the quest to build aquantum computer using silicon components,which are prized for their low cost and versatility compared to the hardware in today’s quantum computers.The team showed that asilicon-spin quantum bit(shown in the box)can communicate with another quantum bit located asignificant distance away on acomputer chip.The feat could enable connections between multiple quantum bits to perform complex calculations. 查看详细>>

Researchers on the project will design and implement methods,tools and databases to advance urban food-systems research in multiple disciplines,including environmental and civil engineering,public policy,earth science and applied economics.The researchers also hope to develop effective methods for influencing people’s behavior related to their diet and food choices.“So little is known about the role of urban food systems in the context of local and global sustainability,”said lead investigator Anu Ramaswami,the Sanjay Swani’87 Professor of India Studies and professor of civil and environmental engineering,the Princeton Institute for International and Regional Studies,and the Princeton Environmental Institute.“Our research group will focus on the co-benefits of urban agriculture and novel food-waste management systems that are being considered in different cities worldwide,”Ramaswami said.“We will be developing methods to assess their benefits to the environment,human health and people’s emotional well-being.The potential benefits include carbon mitigation,healthy diets and nutrition,reducing the effects of extreme heat and flooding,waste reduction,and simply making people happier.” 查看详细>>

Home to about 3million people,one of the world’s busiest airports and sensitive coastal ecosystems,Jamaica Bay is alagoon bordered by Brooklyn and Queens at the southeastern edge of Long Island.This region is vulnerable to an evolving set of threats,including sea-level rise,increasingly intense storms and shifting rainfall patterns.This complexity makes it aperfect place to apply the cross-disciplinary approach that ateam of Princeton researchers is bringing to improving the resilience of New York and other coastal cities.Culminating years of research funded by the National Science Foundation and supported by the Princeton Environmental Institute,the Princeton team recently published a170-page report that details existing conditions,analyzes climate and sea-level trends,and proposes solutions to protect Jamaica Bay’s neighborhoods,infrastructure and ecology.“We are exploring ways to build resilience that is multilayered and multifaceted,”said Guy Nordenson,professor of architecture and affiliated member of the Department of Civil and Environmental Engineering.Along with Nordenson,principal collaborators at Princeton include Ning Lin,associate professor of civil and environmental engineering,and Michael Oppenheimer,the Albert G.Milbank Professor of Geosciences and International Affairs and the Princeton Environmental Institute.In the Jamaica Bay report,the authors propose atwo-tiered set of storm barriers:an outer 6.7-mile barrier linking high ground to the north and south of the bay could be closed to protect John F.Kennedy International Airport and other critical areas against extreme events;while alower,more inland barrier would provide passive protection against tidal flooding as sea levels rise,yet preserve the ecology of the marshes. 查看详细>>

The U.S.Department of Energy announced March 15 that Princeton University will continue to manage and operate the DOE’s Princeton Plasma Physics Laboratory,located on Princeton University’s Forrestal Campus in Plainsboro,New Jersey.The extended contract,which runs through March 31,2022,also highlights collaborations among the University,the lab and the DOE.“We are delighted to have this contract extension and continue the critical work at PPPL,”said David McComas,vice president of PPPL and professor of astrophysical sciences.“The University is committed to advancing research and science in the service of society,which includes revitalizing its long-term collaboration with DOE.”PPPL is devoted to creating new knowledge about the physics of plasmas—charged gases—and to developing practical solutions for the creation of fusion energy.Results of PPPL research have ranged from aportable nuclear materials detector for homeland security applications to universally employed computer codes for analyzing and predicting the outcome of fusion experiments.PPPL research is dedicated to enabling the scientific breakthroughs required to develop fusion as asafe,clean and abundant energy source.Princeton has had the honor of being the PPPL contractor since its inception in 1951,when it was called Project Matterhorn and under the leadership of Lyman Spitzer.PPPL is one of 10 national science laboratories overseen by DOE’s Office of Science.As part of the agreement,the University extended the lease on the land PPPL occupies for another 30 years with aone-time payment of$1 for as long as Princeton remains the laboratory’s management and operations contractor.The three-year contract extension also emphasizes collaboration:Princeton will continue to co-sponsor the Facility for Laboratory Reconnection Experiments(FLARE),a powerful new device for advancing research into magnetic reconnection that was assembled at the University and will be housed at PPPL.The agreement specified that the University will fund upgrades to the machine and the DOE will fund project management,infrastructure and commissioning.PPPL researchers will have priority access to anew suite of computing clusters that are run by the University and housed within the Princeton High-Performance Computing Research Center(HPCRC)and will be compatible with DOE Leadership Class Facilities.Princeton will continue supporting recently piloted initiatives for graduate students at PPPL,including first-year fellowships,tuition rebates for fourth-and fifth-year graduate students,and across-over stipend benefit for graduate students from across the University who perform research at the lab.In the past,some of these benefits were only available to students within the plasma physics program of the Department of Astrophysical Sciences;now,they support students from across the University who engage in research at PPPL. 查看详细>>